Commitments and Contingencies Disclosure [Abstract] Schedule of Commitments to Purchase or Sell Schedule of Loans and Leases Receivable, Commitments to Purchase or Sell [Table Text Block] Schedule of Loans and Leases Receivable, Commitments to Purchase or Sell [Table Text Block] Variable Interest Entities [Abstract] Variable Interest Entity Disclosure [Abstract] Variable Interest Entities Variable Interest Entity Disclosure [Text Block] Accounting Changes and Error Corrections [Abstract] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Domain] Initial Application Period Cumulative Effect Transition [Domain] Balances Without Adoption of ASC 606 [Member] Calculated under Revenue Guidance in Effect before Topic 606 [Member] Effect of Change Higher/(Lower) [Member] Difference between Revenue Guidance in Effect before and after Topic 606 [Member] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] ASU 2014-09 [Member] Accounting Standards Update 2014-09 [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Expenses Excluding Interest Operating Expenses [Abstract] Compensation and benefits Labor and Related Expense Taxes on income Income Tax Expense (Benefit) Net income Net Income (Loss) Attributable to Parent Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Preferred Stock [Member] Preferred Stock [Member] Common Stock [Member] Common Stock [Member] Additional Paid-in Capital [Member] Additional Paid-in Capital [Member] Retained Earnings [Member] Retained Earnings [Member] Treasury Stock, at cost [Member] Treasury Stock [Member] Accumulated Other Comprehensive Income (Loss) [Member] AOCI Attributable to Parent [Member] Accounting Standards Update 2014-09 and 2018-02 [Member] Accounting Standards Update 2014-09 And 2018-02 [Member] Accounting Standards Update 2014-09 And 2018-02 [Member] Statement [Line Items] Statement [Line Items] Increase (Decrease) in Stockholders' Equity Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning balance Stockholders' Equity Attributable to Parent Beginning balance (shares) Shares, Outstanding Adoption of accounting standards (Note 2) Cumulative Effect of New Accounting Principle in Period of Adoption Other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), Net of Tax Dividends declared on preferred stock Dividends, Preferred Stock, Cash Dividends declared on common stock Dividends, Common Stock, Cash Stock option exercises and other Stock Option Exercises And Other Stock Option Exercises And Other Share-based compensation and related tax effects Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Other Stockholders' Equity, Other Ending balance (shares) Ending balance Receivables [Abstract] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Financial Instrument Performance Status [Axis] Financial Instrument Performance Status [Axis] Financial Instrument Performance Status [Domain] Financial Instrument Performance Status [Domain] Nonperforming Financial Instruments [Member] Nonperforming Financial Instruments [Member] Class of Financing Receivable, Type [Axis] Class of Financing Receivable, Type [Axis] Class of Financing Receivable, Type [Domain] Class of Financing Receivable, Type [Domain] Nonaccrual Loans [Member] Nonaccrual Loans [Member] Nonaccrual Loans [Member] Other Real Estate Owned [Member] Other Real Estate Owned [Member] Other Real Estate Owned [Member] Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Total nonperforming assets Loans and Leases Receivable, Net of Deferred Income Troubled debt restructurings Financing Receivable, Modifications, Post-Modification Recorded Investment Total impaired assets Impaired Financing Receivable, with Related Allowance, Recorded Investment Statement of Cash Flows [Abstract] Cash Flows from Operating Activities Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to net cash provided by (used for) operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Share-based compensation Share-based Compensation Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Premium amortization, net, on available for sale and held to maturity securities Accretion (Amortization) of Discounts and Premiums, Investments Other Other Noncash Income (Expense) Net change in: Increase (Decrease) in Operating Capital [Abstract] Investments segregated and on deposit for regulatory purposes Increase (Decrease) In Investments Segregated And Deposit For Regulatory Purposes Increase (Decrease) In Investments Segregated And Deposit For Regulatory Purposes Receivables from brokers, dealers, and clearing organizations Increase (Decrease) in Receivables from Brokers-Dealers and Clearing Organizations Receivables from brokerage clients Increase Decrease In Receivables From Brokerage Clients The net change during the reporting period in receivables from brokerage clients. Brokerage client balances include margin loans to clients stated net of allowance for doubtful accounts. Other securities owned Increase (Decrease) in Financial Instruments Used in Operating Activities Other assets Increase (Decrease) in Other Operating Assets Payables to brokers, dealers, and clearing organizations Increase (Decrease) in Payables to Broker-Dealers and Clearing Organizations Payables to brokerage clients Increase (Decrease) in Payables to Customers Accrued expenses and other liabilities Increase (Decrease) in Accrued Liabilities Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash Flows from Investing Activities Net Cash Provided by (Used in) Investing Activities [Abstract] Purchases of available for sale securities Payments to Acquire Available-for-sale Securities, Debt Proceeds from sales of available for sale securities Proceeds from Sale of Available-for-sale Securities, Debt Principal payments on available for sale securities Proceeds from Maturities, Prepayments and Calls of Available-for-sale Securities Purchases of held to maturity securities Payments to Acquire Held-to-maturity Securities Principal payments on held to maturity securities Proceeds from Maturities, Prepayments and Calls of Held-to-maturity Securities Net increase in bank loans Payments for (Proceeds from) Loans and Leases Purchases of equipment, office facilities, and property Payments to Acquire Property, Plant, and Equipment Purchases of Federal Home Loan Bank stock Payments to Acquire Federal Home Loan Bank Stock Proceeds from sales of Federal Home Loan Bank stock Proceeds from Sale of Federal Home Loan Bank Stock Other investing activities Payments for (Proceeds from) Other Investing Activities Net cash provided by (used for) investing activities Net Cash Provided by (Used in) Investing Activities Cash Flows from Financing Activities Net Cash Provided by (Used in) Financing Activities [Abstract] Net change in bank deposits Increase (Decrease) in Deposits Net change in short-term borrowings Proceeds from (Repayments of) Short-term Debt Issuance of long-term debt Proceeds from Issuance of Long-term Debt Repayment of long-term debt Repayments of Long-term Debt Dividends paid Payments of Dividends Proceeds from stock options exercised and other Proceeds from Stock Options Exercised Other financing activities Proceeds from (Payments for) Other Financing Activities Net cash provided by (used for) financing activities Net Cash Provided by (Used in) Financing Activities Increase (Decrease) in Cash and Cash Equivalents, including Amounts Restricted Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect Cash and Cash Equivalents including Amounts Restricted at Beginning of Year Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash and Cash Equivalents, including Amounts Restricted at End of Period Supplemental Cash Flow Information Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract] Cash paid during the period for: Cash Paid During Period For [Abstract] Cash Paid During Period For [Abstract] Interest Interest Paid Income taxes Income Taxes Paid Non-cash investing activity: Noncash Investing and Financing Items [Abstract] Securities purchased during the period but settled after period end Transfer to Investments Investments, Debt and Equity Securities [Abstract] Schedule of Held-to-maturity Securities [Table] Schedule of Held-to-maturity Securities [Table] Federal Home Loan Bank Branch [Axis] Federal Home Loan Bank Branch [Axis] Federal Home Loan Bank Branch [Domain] Federal Home Loan Bank Branch [Domain] Federal Home Loan Bank of San Francisco [Member] Federal Home Loan Bank of San Francisco [Member] Lender Name [Axis] Lender Name [Axis] Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Federal Reserve Bank Advances [Member] Federal Reserve Bank Advances [Member] Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] Deposits [Member] Deposits [Member] Schedule of Held-to-maturity Securities [Line Items] Schedule of Held-to-maturity Securities [Line Items] Securities pledged as collateral Held-to-maturity Securities Pledged as Collateral OTTI recognized in earnings or other comprehensive income Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net Banking and Thrift [Abstract] Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table] Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] CSC [Member] Charles Schwab Corporation [Member] Charles Schwab Corporation [Member] CSB [Member] Charles Schwab Bank [Member] Charles Schwab Bank [Member] Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] Common Equity Tier 1 Risk-Based Capital Common Equity Tier One Risk-Based Capital [Abstract] Common Equity Tier One Risk-Based Capital [Abstract] Actual Amount Common Equity Tier One Risk-Based Capital Common Equity Tier 1 Risk Based Capital as defined in the regulations. Actual Ratio Common Equity Tier One Risk Based Capital to Risk Weighted Assets Common Equity Tier 1 capital divided by risk weighted assets as defined by regulations. Minimum to be Well Capitalized Amount Common Equity Tier One Risk Based Capital Required to be Well Capitalized The amount of Common Equity Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action. Minimum to be Well Capitalized Ratio Common Equity Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets The Common Equity Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action. Minimum Capital Requirement Amount Common Equity Tier One Risk Based Capital Required for Capital Adequacy The minimum amount of Common Equity Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action. Minimum Capital Requirement Ratio Common Equity Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets The minimum Common Equity Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. Tier 1 Risk-Based Capital Tier One Risk Based Capital [Abstract] Actual Amount Tier One Risk Based Capital Actual Ratio Tier One Risk Based Capital to Risk Weighted Assets Minimum to be Well Capitalized Amount Tier One Risk Based Capital Required to be Well Capitalized Minimum to be Well Capitalized Ratio Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets Minimum Capital Requirement Amount Tier One Risk Based Capital Required for Capital Adequacy Minimum Capital Requirement Ratio Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets Total Risk-Based Capital Capital [Abstract] Actual Amount Capital Actual Ratio Capital to Risk Weighted Assets Minimum to be Well Capitalized Amount Capital Required to be Well Capitalized Minimum to be Well Capitalized Ratio Capital Required to be Well Capitalized to Risk Weighted Assets Minimum Capital Requirement Amount Capital Required for Capital Adequacy Minimum Capital Requirement Ratio Capital Required for Capital Adequacy to Risk Weighted Assets Tier 1 Leverage Tier One Leverage Capital [Abstract] Actual Amount Tier One Leverage Capital Actual Ratio Tier One Leverage Capital to Average Assets Minimum to be Well Capitalized Amount Tier One Leverage Capital Required to be Well Capitalized Minimum to be Well Capitalized Ratio Tier One Leverage Capital Required to be Well Capitalized to Average Assets Minimum Capital Requirement Amount Tier One Leverage Capital Required for Capital Adequacy Minimum Capital Requirement Ratio Tier One Leverage Capital Required for Capital Adequacy to Average Assets Segment Reporting [Abstract] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Segments [Axis] Segments [Axis] Segment [Domain] Segments [Domain] Investor Services [Member] Investor Services [Member] Investor Services [Member] Advisor Services [Member] Advisor Services [Member] Advisor Services [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Net Revenues Revenues [Abstract] Net interest revenue Interest Income (Expense), Net Asset management and administration fees Fees and Commissions Trading revenue Trading Revenue Amount of commission revenue from buying and selling securities on behalf of customers as wells as the amount of gain (loss) resulting from the difference between the acquisition price and the selling price or fair value of trading assets and trading liabilities, conducted separately from customer trading activities. Includes, but is not limited to, changes in fair value of trading assets and trading liabilities. Other Other Income Total net revenues Revenues Expenses Excluding Interest Noninterest Expense Income before taxes on income Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Schedule of New Accounting Pronouncements Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Introduction and Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Document and Entity Information [Abstract] Document and Entity Information [Abstract] Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Trading Symbol Trading Symbol Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Proceeds Proceeds from Sale of Available-for-sale Securities Gross realized gains Available-for-sale Securities, Gross Realized Gains Composition of Bank Loans and Delinquency Analysis by Loan Segment Schedule Of Bank Loans By Loan Segment And Past Due Financing Receivables [Table Text Block] Tabular disclosure of the composition of the loan portfolio by loan segment of financing receivables that are past due but not impaired, financing receivables that are 90 days past due and still accruing, and financing receivables on nonaccrual status. Changes in Allowance for Loan Losses Allowance for Credit Losses on Financing Receivables [Table Text Block] Impaired Bank Loan Related Assets Impaired Financing Receivables [Table Text Block] Credit Quality Indicators of Bank Loan Portfolio Financing Receivable Credit Quality Indicators [Table Text Block] Converting to Amortizing Loans Schedule of Financing Receivable, Convert to Amortizing Loans [Table Text Block] Schedule of Financing Receivable, Convert to Amortizing Loans [Table Text Block] Loss Contingencies [Table] Loss Contingencies [Table] Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Margin Requirements [Member] Margin Requirements [Member] Margin requirements [Member] Bond Market Fund Litigation [Member] Bond Market Fund Litigation [Member] Bond Market Fund Litigation [Member] Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Domain] Guarantor Obligations, Nature [Domain] Performance Guarantee [Member] Performance Guarantee [Member] Asset Class [Axis] Asset Class [Axis] Asset Class [Domain] Asset Class [Domain] CMOs and Mortgage-backed Securities [Member] Collateralized Mortgage Backed Securities [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Aggregate face amount of letter of credit agreements Letter of Credit, Current Borrowing Capacity Letter of Credit, Current Borrowing Capacity Funds drawn under LOC's Long-term Letter of Credit Long-term Letter of Credit Liability for guarantees Guarantor Obligations, Current Carrying Value Alleged minimum percentage of fund assets invested in CMOs and mortgage-backed securities without obtaining shareholder vote, more than Maximum Amount of Fund Assets Allowable Without Obtaining Fundholder Vote, Percentage Alleged minimum percentage of fund assets invested in CMOs and mortgage-backed securities without obtaining shareholder vote Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Earnings Per Share [Abstract] EPS under Basic and Diluted Computations Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Number of reportable segments Number of Reportable Segments Earnings Per Common Share Earnings Per Share [Text Block] First Mortgage and HELOC [Member] First Mortgage And Home Equity [Member] First Mortgage And Home Equity [Member] Adjustable Rate First Mortgage [Member] Adjustable Rate First Mortgage [Member] Adjustable Rate First Mortgage [Member] HELOCs [Member] Home Equity Line of Credit [Member] Home Equity Secured By Second Liens [Member] Home Equity Secured By Second Liens [Member] Home Equity Secured By Second Liens [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum [Member] Minimum [Member] Maximum [Member] Maximum [Member] Loans pledged as collateral Loans Pledged as Collateral Bank loans Mortgage Loans on Real Estate, Carrying Amount of Mortgages Fixed rate interest rate period Mortgage Loans on Real Estate, Fixed Rate Interest Rate Period Mortgage Loans on Real Estate, Fixed Rate Interest Rate Period Percent of loans with interest-only payments Mortgage Loans on Real Estate, Percent of Loans with Interest-Only Payments Mortgage Loans on Real Estate, Percent of Loans with Interest-Only Payments Percent of interest only adjustable rate Mortgage Loans on Real Estate, Percent of Interest Only Adjustable Rate Mortgage Loans on Real Estate, Percent of Interest Only Adjustable Rate Interest-only reset period Mortgage Loans on Real Estate, Interest-Only Reset Period Mortgage Loans on Real Estate, Interest-Only Reset Period Loan term Financing Receivable, Loan Term Financing Receivable, Loan Term Initial draw period Financing Receivable, Initial Draw Period Financing Receivable, Initial Draw Period Converting to amortizing loans period Financing Receivable, Convert to Amortizing Loans, Period Financing Receivable, Convert to Amortizing Loans, Period Total bank loans Loans and Leases Receivable, Gross, Consumer, Real Estate Percent of loan balance outstanding, borrowers paid only minimum due Financing Receivable, Percent of Loan Balance Outstanding, Borrowers Paid Only Minimum Due Financing Receivable, Percent of Loan Balance Outstanding, Borrowers Paid Only Minimum Due Equity [Abstract] Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Net unrealized gain (loss) on available for sale securities [Member] Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] Reclassification of net unrealized loss on securities transferred to held to maturity [Member] Other Comprehensive Income (Loss) Reclassification of Securities Transferred to Held to Maturity [Member] Other Comprehensive Income (Loss) Reclassifications [Member] Other reclassifications in other revenue, available for sale securities [Member] Accumulated Other Comprehensive Income, Other Reclassifications in Other Revenue [Member] Accumulated Other Comprehensive Income, Other Reclassifications in Other Revenue [Member] Reclassification of net unrealized loss on securities transferred from available for sale [Member] Other Comprehensive Income (Loss) Reclassification of Securities Transferred From Available for Sale [Member] Other Comprehensive Income (Loss) Reclassification of Securities Transferred From Available for Sale [Member] Amortization of amounts previously recorded upon transfer to held to maturity from available for sale [Member] Accumulated Amortization of Held to Maturity Securities from Available for Sale Attributable to Parent [Member] Accumulated Amortization of Held to Maturity Securities from Available for Sale Attributable to Parent [Member] Other [Member] Other Accumulated Other Comprehensive Income [Member] Other Accumulated Other Comprehensive Income [Member] Adoption of accounting standards [Member] Adoption Of New Accounting Standards [Member] Adoption Of New Accounting Standards [Member] ASU 2018-02 [Member] Accounting Standards Update 2018-02 [Member] Accounting Standards Update 2018-02 [Member] Accumulated Other Comprehensive Income [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income AOCI Attributable to Parent, Net of Tax [Roll Forward] Beginning Balance Accumulated Other Comprehensive Income (Loss), Net of Tax Other net changes Ending Balance CSSB [Member] Charles Schwab Signature Bank [Member] Charles Schwab Signature Bank [Member] Total assets Assets Reconciliation of cash, cash equivalents and amounts reported within the balance sheet Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Restricted cash and cash equivalents amounts included in cash and investments segregated and on deposit for regulatory purposes Restricted Cash and Cash Equivalents Total cash and cash equivalents, including amounts restricted shown in the statement of cash flows Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Principles of Consolidation Consolidation, Policy [Policy Text Block] Adoption of New Accounting Standards and New Accounting Standards Not Yet Adopted New Accounting Pronouncements, Policy [Policy Text Block] Statement of Financial Position [Abstract] Cash and investments segregated and on deposit for regulatory purposes, resale agreements Securities Purchased under Agreements to Resell Preferred stock, par value (USD per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, aggregate liquidation preference Preferred Stock, Liquidation Preference, Value Common stock, shares authorized (shares) Common Stock, Shares Authorized Common stock, par value (USD per share) Common Stock, Par or Stated Value Per Share Common stock, shares issued (shares) Common Stock, Shares, Issued Treasury stock (shares) Treasury Stock, Shares Segment Information Segment Reporting Disclosure [Text Block] Fair Value Disclosures [Abstract] Fair Value Hierarchy for Assets and Liabilities Measured at Fair Value on a Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Fair Value of Other Financial Instruments Schedule Of Fair Value Assets And Liabilities For Financial Instruments Not Recorded At Fair Value Table [Table Text Block] Tabular disclosure of assets and liabilities by class that are not recorded at fair value. The disclosures that may be required or desired include: (a) the carrying value and (b) the level within the fair value hierarchy in which the carrying value falls, segregating fair value measurements using quoted prices in active markets for identical assets or liabilities (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). Where the quoted price in an active market for the identical liability is not available, the Level 1 input is the quoted price of an identical liability when traded as an asset. Offsetting [Abstract] Financial Instruments Subject to Off-Balance Sheet Credit Risk Offsetting Assets and Liabilities [Text Block] Offsetting Assets and Liabilities [Text Block] Regulatory Requirements Regulatory Capital Requirements Under Banking And Broker Dealer Regulations [Text Block] The entire disclosure for federal savings banks and broker-dealers, for regulatory capital requirements imposed by the Federal Reserve System (FRB), the Federal Deposit Insurance Corporation (FDIC), the Office of the Comptroller of the Currency (OCC), the Securities and Exchange Commission (SEC), and the Commodity Futures Trading Commission (CFTC). Schedule of Variable Interest Entities [Table] Schedule of Variable Interest Entities [Table] Variable Interest Entities [Axis] Variable Interest Entities [Axis] Variable Interest Entity, Classification [Domain] Variable Interest Entity, Classification [Domain] Variable Interest Entity, Not Primary Beneficiary [Member] Variable Interest Entity, Not Primary Beneficiary [Member] Investment [Axis] Investment [Axis] Investment [Domain] Investment [Domain] LIHTC Investments [Member] Low Income Housing Tax Credit Investments [Member] Low-Income Housing Tax Credit Investments [Member] Other CRA Investments [Member] Other Community Reinvestment Act Investments [Member] Other Community Reinvestment Act Investments [Member] Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Aggregate assets Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets Aggregate liabilities Variable Interest Entity, Nonconsolidated, Carrying Amount, Liabilities Maximum exposure to loss Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount Regulatory Capital and Ratios Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table Text Block] Net Capital and Net Capital Requirements Computation of Net Capital under Securities and Exchange Commission Regulation [Table Text Block] Debt Disclosure [Abstract] Borrowings Debt Disclosure [Text Block] Revenue from Contract with Customer [Abstract] Revenue Recognition Revenue from Contract with Customer [Text Block] Subsequent Events [Abstract] Subsequent Event [Table] Subsequent Event [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Senior Notes [Member] Senior Notes [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Senior Notes Due 2024 [Member] Senior Notes Due 2024 [Member] Senior Notes Due 2024 [Member] Senior Notes Due 2029 [Member] Senior Notes Due 2029 [Member] Senior Notes Due 2029 [Member] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event [Member] Subsequent Event [Member] Subsequent Event [Line Items] Subsequent Event [Line Items] Share repurchase, authorized amount Stock Repurchase Program, Authorized Amount Debt issued Senior Notes Fixed interest rate Debt Instrument, Interest Rate, Stated Percentage Assets: Offsetting Derivative Assets [Abstract] Resale agreements Offsetting Securities Purchased under Agreements to Resell [Abstract] Gross Assets Securities Purchased under Agreements to Resell, Gross Gross Amounts Offset in the Condensed Consolidated Balance Sheets Derivative Asset, Collateral, Obligation to Return Cash, Offset Net Amounts Presented in the Condensed Consolidated Balance Sheets Counterparty Offsetting Securities Purchased under Agreements to Resell, Collateral, Obligation to Return Securities Collateral Securities Purchased under Agreements to Resell, Collateral, Obligation to Return Cash Net Amount Securities Purchased under Agreements to Resell, Amount Offset Against Collateral Securities borrowed Offsetting Securities Borrowed [Abstract] Gross Assets Securities Borrowed, Gross Gross Amounts Offset in the Condensed Consolidated Balance Sheets Securities Borrowed, Liability Net Amounts Presented in the Condensed Consolidated Balance Sheets Securities Borrowed Counterparty Offsetting Securities Borrowed, Collateral, Obligation to Return Securities Collateral Securities Borrowed, Collateral, Obligation to Return Cash Net Amount Securities Borrowed, Amount Offset Against Collateral Total Gross Assets Derivative Asset, Fair Value, Gross Asset Total Assets, Gross Amounts Offset in the Condensed Consolidated Balance Sheets Derivative Asset, Securities Purchased under Agreements to Resell, Securities Borrowed, Liability Total Assets, Net Amounts Presented in the Condensed Consolidated Balance Sheets Derivative Asset, Securities Purchased under Agreements to Resell, Securities Borrowed Total Assets, Gross Amounts Not Offset in the Consolidated Balance Sheet, Counterparty Offsetting Derivative, Collateral, Obligation to Return Securities Total Assets, Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Derivative, Collateral, Obligation to Return Cash Total Assets, Net Amount Derivative Asset, Fair Value, Amount Offset Against Collateral Liabilities: Offsetting Derivative Liabilities [Abstract] Securities loaned Offsetting Securities Loaned [Abstract] Gross Liabilities Securities Loaned, Gross Gross Amounts Offset in the Condensed Consolidated Balance Sheets Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned Net Amounts Presented in the Condensed Consolidated Balance Sheets Securities Loaned Counterparty Offsetting Securities Loaned, Collateral, Right to Reclaim Securities Collateral Securities Loaned, Collateral, Right to Reclaim Cash Net Amount Securities Loaned, Amount Offset Against Collateral Total Gross Liabilities Derivative Liability, Fair Value, Gross Liability Total Liabilities, Net Amounts Presented in the Consolidated Balance Sheet Derivative Liability Total Liabilities, Gross Amounts Not Offset in the Consolidated Balance Sheet, Counterparty Offsetting Derivative, Collateral, Right to Reclaim Securities Total Liabilities, Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Derivative, Collateral, Right to Reclaim Cash Total Liabilities, Net Amount Derivative Liability, Fair Value, Amount Offset Against Collateral Offsetting Assets [Table] Offsetting Assets [Table] Securities Financing Transaction [Axis] Securities Financing Transaction [Axis] Securities Financing Transaction [Domain] Securities Financing Transaction [Domain] Resale And Repurchase Agreements [Member] Resale And Repurchase Agreements [Member] Resale And Repurchase Agreements [Member] Offsetting Assets [Line Items] Offsetting Assets [Line Items] Percentage of collateral to related assets Percentage Of Collateral To Related Assets Percentage Of Collateral To Related Assets Fair value of client securities available to be pledged Fair Value of Securities Received as Collateral that Can be Resold or Repledged Income Tax Disclosure [Abstract] Effective tax rate Effective Income Tax Rate Reconciliation, Percent One-time non-cash charge to taxes on income Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Deferred Tax Asset, Provisional Income Tax Expense Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Deferred Tax Asset, Provisional Income Tax Expense Retained earnings Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect Disaggregation of Schwab's Revenue Disaggregation of Revenue [Table Text Block] Assets Assets [Abstract] Cash and investments segregated and on deposit for regulatory purposes (including resale agreements of $4,424 at September 30, 2018 and $6,596 at December 31, 2017) Cash and Securities Segregated under Federal and Other Regulations Receivables from brokers, dealers, and clearing organizations Receivables from Brokers-Dealers and Clearing Organizations Receivables from brokerage clients — net Receivables from Customers Other securities owned — at fair value Financial Instruments, Owned, at Fair Value Available for sale securities Available-for-sale Securities, Debt Securities Held to maturity securities Held-to-maturity Securities Bank loans — net Loans and Leases Receivable, Net Amount Equipment, office facilities, and property — net Property, Plant and Equipment, Net Goodwill Goodwill Other assets Other Assets Total assets Liabilities and Stockholders’ Equity Liabilities and Equity [Abstract] Bank deposits Deposits Payables to brokers, dealers, and clearing organizations Payables to Broker-Dealers and Clearing Organizations Payables to brokerage clients Payables to Customers Accrued expenses and other liabilities Accrued Liabilities Short-term borrowings Short-term Debt Long-term debt Long-term Debt and Capital Lease Obligations Total liabilities Liabilities Stockholders’ equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock — $.01 par value per share; aggregate liquidation preference of $2,850 Preferred Stock, Value, Issued Common stock — 3 billion shares authorized; $.01 par value per share; 1,487,543,446 shares issued Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital Retained earnings Retained Earnings (Accumulated Deficit) Treasury stock, at cost — 135,806,047 shares at September 30, 2018 and 142,210,890 shares at December 31, 2017 Treasury Stock, Value Accumulated other comprehensive income (loss) Total stockholders’ equity Total liabilities and stockholders’ equity Liabilities and Equity 2018 Long-term Debt and Capital Lease Obligations, Repayments of Principal in Next Twelve Months 2019 Long-term Debt and Capital Lease Obligations, Maturities, Repayments of Principal in Year Two 2020 Long-term Debt and Capital Lease Obligations, Maturities, Repayments of Principal in Year Three 2021 Long-term Debt and Capital Lease Obligations, Maturities, Repayments of Principal in Year Four 2022 Long-term Debt and Capital Lease Obligations, Maturities, Repayments of Principal in Year Five Thereafter Long-term Debt and Capital Lease Obligations, Maturities, Repayments of Principal after Year Five Total maturities Long-term Debt, Gross Unamortized discount, net Debt Instrument, Unamortized Discount Debt issuance costs Debt Issuance Costs, Net Total long-term debt Fair Values of Assets and Liabilities Fair Value Disclosures [Text Block] Offsetting Assets and Liabilities Offsetting Assets and Liabilities [Table Text Block] Offsetting Assets and Liabilities Summary of the Fair Value of Client Securities Available to Utilize as Collateral and Amounts Pledged Schedule of Securities Financing Transactions, Securities Available to Utilize as Collateral and Amounts Pledged [Table Text Block] Schedule of Securities Financing Transactions, Securities Available to Utilize as Collateral and Amounts Pledged [Table Text Block] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] U.S. agency mortgage-backed securities [Member] Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] U.S. Treasury securities [Member] US Treasury Securities [Member] Asset-backed securities [Member] Asset-backed Securities [Member] Corporate debt securities [Member] Corporate Debt Securities [Member] Certificates of deposit [Member] Certificates of Deposit [Member] U.S. agency notes [Member] US Government Agencies Debt Securities [Member] U.S. state and municipal securities [Member] US States and Political Subdivisions Debt Securities [Member] Commercial paper [Member] Commercial Paper [Member] Foreign government agency securities [Member] Foreign Government Debt Securities [Member] Non-agency commercial mortgage-backed securities [Member] Commercial Mortage Backed Securities Issued By Private Enterprises [Member] Commercial Mortage Backed Securities Issued by Private Enterprises [Member] Other [Member] Other Debt Obligations [Member] Schedule of Available-for-sale Securities [Line Items] Schedule of Available-for-sale Securities [Line Items] Available for sale securities, fair value Available-for-sale Securities, Debt Maturities, Single Maturity Date [Abstract] Within 1 year Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value After 1 year through 5 years Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value After 5 years through 10 years Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value After 10 years Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value Fair Value Available for sale securities, amortized cost Available-for-sale Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis [Abstract] Within 1 year Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis After 1 year through 5 years Available-for-sale Securities, Debt Maturities, Year Two Through Five, Amortized Cost Basis After 5 years through 10 years Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Amortized Cost Basis After 10 years Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis Amortized Cost Available-for-sale Debt Securities, Amortized Cost Basis Held to maturity securities, fair value Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Fair Value [Abstract] Within 1 year Held-to-maturity Securities, Debt Maturities, Next Twelve Months, Fair Value After 1 year through 5 years Held-to-maturity Securities, Debt Maturities, Year Two Through Five, Fair Value After 5 years through 10 years Held-to-maturity Securities, Debt Maturities, Year Six Through Ten, Fair Value After 10 years Held-to-maturity Securities, Debt Maturities, after Ten Years, Fair Value Fair Value Held-to-maturity Securities, Fair Value Held to maturity securities, amortized cost Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis [Abstract] Within 1 year Held-to-maturity Securities, Debt Maturities, within One Year, Net Carrying Amount After 1 year through 5 years Held-to-maturity Securities, Debt Maturities, after One Through Five Years, Net Carrying Amount After 5 years through 10 years Held-to-maturity Securities, Debt Maturities, after Five Through Ten Years, Net Carrying Amount After 10 years Held-to-maturity Securities, Debt Maturities, after Ten Years, Net Carrying Amount Amortized Cost Deferred contract cost Capitalized Contract Cost, Net Amortization expense Capitalized Contract Cost, Amortization Receivables from contracts with customers Contract with Customer, Asset, Net Statement of Comprehensive Income [Abstract] Net income Other comprehensive income (loss), before tax: Other Comprehensive Income (Loss), before Tax [Abstract] Change in net unrealized gain (loss) on available for sale securities: Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax [Abstract] Net unrealized gain (loss) Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax Reclassification of net unrealized loss transferred to held to maturity Other Comprehensive Income (Loss), Reclassification Adjustment From Available-for-sale to Held-To-Maturity, Before Tax Other Comprehensive Income (Loss), Reclassification Adjustment From Available-for-sale to Held-To-Maturity, Before Tax Other reclassifications included in other revenue Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax Change in net unrealized gain (loss) on held to maturity securities: Other Comprehensive Loss, Held-to-maturity Security, OTTI, before Tax, after Adjustments, Attributable to Parent [Abstract] Reclassification of net unrealized loss transferred from available for sale Other Comprehensive Loss, Held-to-maturity Security, Reclassification Adjustment from Securities Transferred from Available for Sale Before Tax Other Comprehensive Loss, Held-to-maturity Security, Reclassification Adjustment from Securities Transferred from Available for Sale, Before Tax Amortization of amounts previously recorded upon transfer from available for sale Other Comprehensive Loss, Held-to-maturity Security, Transferred From Available for Sale, Amortization, Before Tax Other Comprehensive Loss, Held-to-maturity Security, Transferred From Available for Sale, Amortization, Before Tax Other Other Comprehensive Income, Other, Before Tax Other Comprehensive Income, Other, Before Tax Other comprehensive income (loss), before tax Other Comprehensive Income (Loss), before Tax Income tax effect Other Comprehensive Income (Loss), Tax Other comprehensive income (loss), net of tax Comprehensive Income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Commitment, expected payment date Investment, Commitment, Expected Payment Date Investment, Commitment, Expected Payment Date Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table] Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table] First Mortgage [Member] First Mortgage [Member] Pledged asset lines [Member] Pledged Asset Lines [Member] Pledged Asset Lines [Member] Loan to Value [Axis] Loan to Value [Axis] Loan to Value [Domain] Loan to Value [Domain] Estimated Current LTV 70% and Below [Member] Estimated Current Loan To Value Ratio Seventy Percent And Below [Member] Estimated Current Loan to Value Ratio Seventy Percent and Below [Member] Estimated Current LTV Greater Than 70% through 90% [Member] Estimated Current Loan To Value Ratio Greater Than Seventy Percent Through Ninety Percent [Member] Estimated Current Loan To Value Ratio Greater Than Seventy Percent Through Ninety Percent [Member] Estimated Current LTV Greater Than 90% through 100% [Member] Estimated Current Loan To Value Ratio Greater Than Ninety Percent Through One Hundred Percent [Member] Estimated Current Loan To Value Ratio Greater Than Ninety Percent Through One Hundred Percent [Member] Estimated Current LTV Greater Than 100% [Member] Estimated Current Loan To Value Ratio Greater Than One Hundred Percent [Member] Estimated Current Loan To Value Ratio Greater Than One Hundred Percent [Member] Weighted Average Loan to Value Ratio =70% [Member] Weighted Average Loan To Value Ratio Equal To Seventy Percent [Member] Weighted Average Loan to Value Ratio Equal to Seventy Percent [Member] Origination Loan to Value Ratio 70% and Below [Member] Origination Loan To Value Ratio Seventy Percent And Below [Member] Origination Loan To Value Ratio 70 Percent And Below [Member] Origination Loan to Value Ratio Greater Than 70% Through 90% [Member] Origination Loan To Value Ratio Greater Than Seventy Percent Through Ninety Percent [Member] Origination Loan To Value Ratio Greater Than Seventy Percent Through Ninety Percent [Member] Origination Loan to Value Ratio Greater Than 90% Through 100% [Member] Origination Loan To Value Ratio Greater Than Ninety Percent Through One Hundred Percent [Member] Origination Loan to Value Ratio Greater Than Ninety Percent Through One Hundred Percent [Member] Credit Rating Source [Axis] Credit Rating Source [Axis] Credit Rating Source [Domain] Credit Rating Source [Domain] Year of origination Pre 2014 [Member] Year Of Origination One [Member] Year of Origination, One [Member] Year of origination 2014 [Member] Year Of Origination Two [Member] Year of Origination, Two [Member] Year of origination 2015 [Member] Year Of Origination Three [Member] Year of Origination, Three [Member] Year of origination 2016 [Member] Year Of Origination Four [Member] Year of Origination, Four [Member] Year of origination 2017 [Member] Year Of Origination Five [Member] Year of Origination, Five [Member] Year of origination 2018 [Member] Year Of Origination Six [Member] Year of Origination, Six [Member] Credit Score, FICO [Axis] Credit Score, FICO [Axis] Credit Score, FICO [Domain] Credit Score, FICO [Domain] Origination FICO Score Below 620 [Member] Origination Fico Score Below Six Hundred Twenty [Member] Origination FICO Score Below 620 [Member] Origination FICO Score 620 Through 679 [Member] Origination Fico Score Six Hundred Twenty Through Six Hundred Seventy Nine [Member] Origination FICO Score 620 Through 679 [Member] Origination FICO Score 680 Through 739 [Member] Origination Fico Score Six Hundred Eighty Through Seven Hundred Thirty Nine [Member] Origination FICO Score 680 Through 739 [Member] Origination FICO Score 740 and Above [Member] Origination Fico Score Seven Hundred Forty And Above [Member] Origination FICO Score 740 And Above [Member] Financing Receivable, Recorded Investment [Line Items] Financing Receivable, Recorded Investment [Line Items] Balance Weighted Average Updated FICO Financing Receivable Credit Quality Weighted Average Credit Ratings Updated Financing Receivable, Credit Quality, Weighted Average Credit Ratings Updated Utilization Rate Financing Receivable Credit Quality Utilization Rate Financing Receivable, Credit Quality, Utilization Rate Percent of Loans on Nonaccrual Status Loans and Leases Receivable, Ratio of Nonperforming Loans to All Loans Available for sale securities: Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] Less than 12 months Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value Less than 12 months Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 12 months or longer Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value 12 months or longer Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Total Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value Total Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss Held to maturity securities: Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract] Less than 12 months Fair Value Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value Less than 12 months Unrealized Losses Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 12 months or longer Fair Value Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value 12 months or longer Unrealized Losses Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Total Fair Value Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value Total Unrealized Losses Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss Total securities with unrealized losses Continuous Unrealized Loss Position [Abstract] Continuous Unrealized Loss Position [Abstract] Less than 12 months Fair Value Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value This item represents the fair value of securities that have been in a continuous unrealized loss position for less than twelve months. Less than 12 months Unrealized Losses Securities Continuous Unrealized Loss Position Less Than Twelve Months Aggregate Loss Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Aggregate Loss 12 months or longer Fair Value Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value This item represents the fair value of securities that have been in a continuous unrealized loss position for twelve months or longer. 12 months or longer Unrealized Losses Securities Continuous Unrealized Loss Position Twelve Months Or Longer Aggregate Loss Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Aggregate Loss Total Fair Value Securities With Unrealized Losses Total Fair Value This item represents the total fair value of securities in an unrealized loss position. Total Unrealized Losses Securities With Unrealized Losses Total Unrealized Loss Securities with Unrealized Losses Total Unrealized Loss Number of available for sale securities in unrealized loss positions Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions Number of held to maturity securities in unrealized loss positions Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions Stockholders’ Equity Capitalized contract cost Deferred tax liability Deferred Tax Liabilities, Net Schedule of Financing Receivable, Allowance for Credit Losses [Table] Schedule of Financing Receivable, Allowance for Credit Losses [Table] Other [Member] Other Loans [Member] Other Loans [Member] Financing Receivable, Allowance for Credit Losses [Line Items] Financing Receivable, Allowance for Credit Losses [Line Items] Allowance for Loan and Lease Losses [Roll Forward] Allowance for Loan and Lease Losses [Roll Forward] Balance at beginning of period Loans and Leases Receivable, Allowance Charge-offs Allowance for Loan and Lease Losses, Write-offs Recoveries Valuation Allowances and Reserves, Additions for Recoveries Provision for loan losses Provision for Loan and Lease Losses Balance at end of period Line of Credit Facility [Table] Line of Credit Facility [Table] Federal Home Loan Bank Advances [Member] Federal Home Loan Bank Advances [Member] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Secured Credit Facility [Member] Secured Debt [Member] Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Borrowings on line of credit Long-term Line of Credit Line of credit facility, current borrowing capacity Line of Credit Facility, Current Borrowing Capacity FHLB stock Federal Home Loan Bank Stock Components of Other Comprehensive Income (Loss) Comprehensive Income (Loss) [Table Text Block] Accumulated Other Comprehensive Income Balances Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] ASU 2016-02 [Member] Accounting Standards Update 2016-02 [Member] Capitalized costs Capitalized Contract Cost, Gross Percentage of total assets Lease Assets And Liabilities, Percentage Of Total Assets Lease Assets and Liabilities, Percentage of Total Assets Bank Deposits Deposit Liabilities Disclosures [Text Block] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Measurement Basis [Axis] Measurement Basis [Axis] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Portion at Fair Value Measurement [Member] Portion at Fair Value Measurement [Member] Carrying Amount [Member] Reported Value Measurement [Member] Portion at Other than Fair Value Measurement [Member] Portion at Other than Fair Value Measurement [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Level 1 [Member] Fair Value, Inputs, Level 1 [Member] Level 2 [Member] Fair Value, Inputs, Level 2 [Member] Level 3 [Member] Fair Value, Inputs, Level 3 [Member] Other [Member] Other Securities [Member] Other Securities [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Assets Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] Cash and cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Cash and investments segregated and on deposit for regulatory purposes Cash And Securities Segregated Under Federal And Other Regulations Fair Value Disclosure Cash And Securities Segregated Under Federal And Other Regulations, Fair Value Disclosure Receivables from brokers, dealers, and clearing organizations Receivables From Brokers Dealers And Clearing Organizations Fair Value Disclosure Receivables From Brokers Dealers And Clearing Organizations, Fair Value Disclosure Receivables from brokerage clients — net Accounts Receivable, Fair Value Disclosure Held to maturity securities Bank loans – net Loans Receivable, Fair Value Disclosure Other assets Other Assets, Fair Value Disclosure Total Assets, Fair Value Disclosure Liabilities Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] Bank deposits Deposits, Fair Value Disclosure Payables to brokers, dealers, and clearing organizations Payables To Broker Dealers And Clearing Organizations Fair Value Disclosure Payables To Broker Dealers And Clearing Organizations, Fair Value Disclosure Payables to brokerage clients Payables To Customers, Fair Value Disclosure Fair value portion of liabilities incurred for customers payables. Accrued expenses and other liabilities Accrued Liabilities, Fair Value Disclosure Short-term borrowings Short-term Debt, Fair Value Long-term debt Long-term Debt, Fair Value Total Financial Liabilities Fair Value Disclosure Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Products and Services [Axis] Products and Services [Axis] Products and Services [Domain] Products and Services [Domain] Mutual funds and ETF service fees [Member] Investment Performance [Member] Investment Performance [Member] Advice solutions [Member] Investment Advice [Member] Investment Advice [Member] Other [Member] Financial Service Other [Member] Financial Service Other [Member] Commissions [Member] Commissions [Member] Commissions [Member] Principal Transactions [Member] Principal Transactions [Member] Principal Transactions [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Interest revenue Interest Income, Operating Interest expense Interest Expense Net interest revenue Other Other comprehensive income (loss) before tax Reclassification of net unrealized loss on securities transferred to held to maturity Change in net unrealized gain (loss) on held to maturity securities: Reclassification of net unrealized loss on securities transferred from available for sale Tax Effect Other Comprehensive Income (Loss), Tax [Abstract] Net unrealized gain (loss) Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax Reclassification of net unrealized loss on securities transferred to held to maturity Other Comprehensive Income (Loss), Reclassification Adjustment From Available-for-sale to Held-To-Maturity, Tax Other Comprehensive Income (Loss), Reclassification Adjustment From Available-for-sale to Held-To-Maturity, Tax Other reclassifications included in other revenue Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax Change in net unrealized gain (loss) on held to maturity securities: Other Comprehensive Loss, Held-to-maturity Security, OTTI, after Adjustments, Tax, Attributable to Parent [Abstract] Reclassification of net unrealized loss on securities transferred from available for sale (1) Other Comprehensive Loss, Held-to-maturity Security, Reclassification Adjustment from Securities Transferred from Available for Sale, Tax Other Comprehensive Loss, Held-to-maturity Security, Reclassification Adjustment from Securities Transferred from Available for Sale, Tax Amortization of amounts previously recorded upon transfer from available for sale Other Comprehensive Loss, Held-to-maturity Security, Transferred From Available for Sale, Amortization, Tax Other Comprehensive Loss, Held-to-maturity Security, Transferred From Available for Sale, Amortization, Tax Other Other Comprehensive Income, Other, Tax Other Comprehensive Income, Other, Tax Other comprehensive income (loss) Net of Tax Other Comprehensive Income (Loss), Net of Tax [Abstract] Net unrealized gain (loss) Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax Reclassification of net unrealized loss on securities transferred to held to maturity Other Comprehensive Income (Loss), Reclassification Adjustment From Available-for-sale to Held-To-Maturity, Net of Tax Other Comprehensive Income (Loss), Reclassification Adjustment From Available-for-sale to Held-To-Maturity, Net of Tax Other reclassifications included in other revenue Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax Change in net unrealized gain (loss) on held to maturity securities: Other Comprehensive Loss, Held-to-maturity Security, OTTI, after Tax and Adjustments, Attributable to Parent [Abstract] Reclassification of net unrealized loss on securities transferred from available for sale Other Comprehensive Loss, Held-to-maturity Security, Reclassification Adjustment from Securities Transferred from Available for Sale, Net of Tax Other Comprehensive Loss, Held-to-maturity Security, Reclassification Adjustment from Securities Transferred from Available for Sale, Net of Tax Amortization of amounts previously recorded upon transfer from available for sale Other Comprehensive Loss, Held-to-maturity Security, Transferred From Available for Sale, Amortization, Net of Tax Other Comprehensive Loss, Held-to-maturity Security, Transferred From Available for Sale, Amortization, Net of Tax Other Other Comprehensive Income, Other, Net of Tax Income Statement [Abstract] Expenses Excluding Interest Noninterest Expense [Abstract] Professional services Professional Fees Occupancy and equipment Occupancy, Net Advertising and market development Marketing and Advertising Expense Communications Communication Regulatory fees and assessments Regulatory Fees And Assessments Regulatory Fees And Assessments Other Other Expenses Total expenses excluding interest Net Income Preferred stock dividends and other Preferred Stock Dividends and Other Adjustments Net Income Available to Common Stockholders Net Income (Loss) Available to Common Stockholders, Basic Weighted-Average Common Shares Outstanding: Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Basic (shares) Weighted Average Number of Shares Outstanding, Basic Diluted (shares) Weighted Average Number of Shares Outstanding, Diluted Earnings Per Common Shares Outstanding: Basic (USD per share) Earnings Per Share, Basic Diluted (USD per share) Earnings Per Share, Diluted Dividends Declared Per Common Share (USD per share) Common Stock, Dividends, Per Share, Declared Interest-bearing deposits: Interest-bearing Deposit Liabilities [Abstract] Deposits swept from brokerage accounts Brokerage Account Sweep Deposits The amount of interest-bearing deposits swept from brokerage accounts. Checking Demand Deposit Accounts Savings and other Savings and Other Deposits Savings and Other Deposits Total interest-bearing deposits Interest-bearing Deposit Liabilities Non-interest-bearing deposits Noninterest-bearing Deposit Liabilities Total bank deposits Investment Securities Securities Available For Sale And Held To Maturity [Text Block] This item represents the entire disclosure related to Available-for-sale and Held to Maturity Securities which consist of all investments in certain debt and equity securities not classified as trading. Held to Maturity Securities are investments in certain debt and equity securities for which the Company has the positive intent and ability to hold until maturity. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. Taxes on Income Income Tax Disclosure [Text Block] Amortized Cost, Gross Unrealized Gains and Losses, and Fair Value of Securities Available for Sale and Securities Held to Maturity Unrealized Gain (Loss) on Investments [Table Text Block] Securities with Unrealized Losses, Aggregated by Category and Period of Continuous Unrealized Loss Schedule of Unrealized Loss on Investments [Table Text Block] Maturities of Securities Available for Sale and Securities Held to Maturity Investments Classified by Contractual Maturity Date [Table Text Block] Proceeds and Gross Realized Gains And Losses from Sales of Securities Available for Sale Schedule of Realized Gain (Loss) [Table Text Block] Aggregate Assets, Liabilities and Maximum Exposure to Loss Schedule of Variable Interest Entities [Table Text Block] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Measurements, Recurring [Member] Fair Value, Measurements, Recurring [Member] Fair Value [Member] Estimate of Fair Value Measurement [Member] Money market funds [Member] Money Market Funds [Member] U.S. Government securities [Member] US Government Debt Securities [Member] Equity and bond mutual funds [Member] Equity And Bond Mutual Funds [Member] Equity And Bond Mutual Funds [Member] Schwab Funds money market funds [Member] Schwab Funds Money Market Funds [Member] Schwab Funds Money Market Funds [Member] State and municipal debt obligations [Member] State And Municipal Debt Obligations [Member] State and Municipal Debt Obligations [Member] Equity, U.S. Government and corporate debt, and other securities [Member] Equity United States Government And Corporate Debt And Other Securities [Member] Equity US Government And Corporate Debt And Other Securities [Member] Fair Value, Assets Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Cash equivalents Investments segregated and on deposit for regulatory purposes Other securities owned Securities Financing Transaction [Table] Securities Financing Transaction [Table] Fulfillment of Requirements with the Options Clearing Corporation [Member] Fulfillment of Requirements with Options Clearing Corporation [Member] Fulfillment of Requirements with Options Clearing Corporation [Member] Fulfillment of Client Short Sales [Member] Fulfillment of Client Short Sales [Member] Fulfillment of Client Short Sales [Member] Securities Lending to Other Broker-Dealers [Member] Securities Lending to Other Broker-Dealers [Member] Securities Lending to Other Broker-Dealers [Member] Fully Paid Client Securities [Member] Fully Paid Client Securities [Member] Fully Paid Client Securities [Member] Securities Financing Transaction [Line Items] Securities Financing Transaction [Line Items] Total collateral pledged Fair Value of Securities Received as Collateral that Have Been Resold or Repledged Stockholders' Equity Stockholders' Equity Note Disclosure [Text Block] Net Capital Net Capital Minimum net capital required Minimum Net Capital Required 2% of aggregate debit balances Two Percent of Debit Items Net Capital in excess of required net capital Alternative Excess Net Capital Subsequent Events Subsequent Events [Text Block] Preferred stock dividends and other Weighted-average common shares outstanding — basic (shares) Common stock equivalent shares related to stock incentive plans (shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Weighted-average common shares outstanding — diluted (shares) Basic EPS (USD per share) Diluted EPS (USD per share) Antidilutive stock options and restricted stock awards excluded from the calculation of diluted EPS (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Accumulated Other Comprehensive Income Comprehensive Income (Loss) Note [Text Block] Deposits from Banking Clients Consisting of Interest Bearing and Noninterest Bearing Deposits Deposits From Banking Clients [Table Text Block] This element may be used as a single block of text to encapsulate the deposits from banking clients table. Converted to an amortizing loan by period end Financing Receivable, Amount Converted to Amortizing Loan by Period End Financing Receivable, Amount Converted to Amortizing Loan by Period End Within 1 year Financing Receivable, Converted to Amortizing Loan, Year One Financing Receivable, Converted to Amortizing Loan, Year One 1 year – 3 years Financing Receivable, Converted to Amortizing Loan, Year One to Year Three Financing Receivable, Converted to Amortizing Loan, Year One to Year Three 3 years – 5 years Financing Receivable, Converted to Amortizing Loan, Year Three to Year Five Financing Receivable, Converted to Amortizing Loan, Year Three to Year Five 5 years Financing Receivable, Converted to Amortizing Loan, Year Five Financing Receivable, Converted to Amortizing Loan, Year Five Total Financing Receivable, Converted to Amortizing Loan Financing Receivable, Converted to Amortizing Loan Bank Loans and Related Allowance for Loan Losses Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Schedule of Fair Value, Off-balance Sheet Risks [Table] Schedule of Fair Value, Off-balance Sheet Risks [Table] Securities Financing Transaction, Fair Value [Member] Securities Financing Transaction, Fair Value [Member] Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] Fair value of borrowed securities from other broker-dealers to fulfill short sales by clients Fair Value Of Securities Borrowed Fair value of securities borrowed. 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