Investment Securities (Amortized Cost, Gross Unrealized Gains and Losses, and Fair Value of Securities Available for Sale) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Available for sale securities
Amortized Cost	$ 391,482	$ 330,248
Gross Unrealized Gains	3,481	7,799
Gross Unrealized Losses	4,909	647
Fair Value	390,054	337,400
U.S. agency mortgage-backed securities [Member]
Available for sale securities
Amortized Cost	335,803	283,911
Gross Unrealized Gains	3,141	7,005
Gross Unrealized Losses	4,589	563
Fair Value	334,355	290,353
U.S. Treasury securities [Member]
Available for sale securities
Amortized Cost	21,394	10,631
Gross Unrealized Gains	13	25
Gross Unrealized Losses	125	0
Fair Value	21,282	10,656
Asset-backed securities [Member]
Available for sale securities
Amortized Cost	17,547	18,808
Gross Unrealized Gains	79	174
Gross Unrealized Losses	80	84
Fair Value	17,546	18,898
Corporate debt securities [Member]
Available for sale securities
Amortized Cost	12,310	12,408
Gross Unrealized Gains	143	388
Gross Unrealized Losses	109	0
Fair Value	12,344	12,796
U.S. state and municipal securities [Member]
Available for sale securities
Amortized Cost	1,611	1,544
Gross Unrealized Gains	81	153
Gross Unrealized Losses	5	0
Fair Value	1,687	1,697
Non-agency commercial mortgage-backed securities [Member]
Available for sale securities
Amortized Cost	1,170	1,213
Gross Unrealized Gains	20	52
Gross Unrealized Losses	0	0
Fair Value	1,190	1,265
Certificates of deposit [Member]
Available for sale securities
Amortized Cost	1,000	300
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1	0
Fair Value	999	300
Foreign government agency securities [Member]
Available for sale securities
Amortized Cost	425	1,411
Gross Unrealized Gains	0	2
Gross Unrealized Losses	0	0
Fair Value	425	1,413
Commercial paper [Member]
Available for sale securities
Amortized Cost	200
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair Value	200
Other [Member]
Available for sale securities
Amortized Cost	22	22
Gross Unrealized Gains	4	0
Gross Unrealized Losses	0	0
Fair Value	$ 26	$ 22
Federal Family Education Loan Program Asset-Backed Securities [Member]
Available for sale securities
Asset-backed securities percent	58.00%	51.00%
Collateralized credit card receivables [Member]
Available for sale securities
Asset-backed securities percent	30.00%	36.00%
Corporate debt securities issued by financial services industry [Member]
Available for sale securities
AFS securities percentage	31.00%	46.00%

Concentration Risk, Asset-Backed Securities

No definition available.

Name:	schw_ConcentrationRiskAssetBackedSecurities
Namespace Prefix:	schw_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Concentration Risk, Available For Sale

+ References

No definition available.

+ Details

Name:	schw_ConcentrationRiskAvailableForSale
Namespace Prefix:	schw_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

+ Details

Name:	us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestBeforeAllowanceForCreditLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

+ Details

Name:	us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_AssetBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=schw_CommercialMortageBackedSecuritiesIssuedByPrivateEnterprisesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CertificatesOfDepositMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ForeignGovernmentDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CommercialPaperMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_OtherDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_FederalFamilyEducationLoanProgramFfelpGuaranteedLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CollateralizedCreditCardSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=schw_CorporateDebtSecuritiesIssuedByFinancialServicesIndustryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: