Loans Held for Sale - Narrative (Details) - USD ($) $ in Millions		3 Months Ended				9 Months Ended
		Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Feb. 28, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans held-for-sale		$ 166				$ 166			$ 48
Total loans held for sale	[1]	576				576			4,217
Revenue (losses) associated with the economic hedging program		(395)			$ (73)	(1,837)	$ 729
Commercial loans held for sale
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans held-for-sale		145				145			23
Retail Branches Sold
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale									2,441
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Retail Branches Sold
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale								$ 2,148
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale		474				474			461
Valuation allowance		13				13			5
Commercial loans | Disposal Group, Disposed of by Sale, Not Discontinued Operations | Retail Branches Sold
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sales of loans held for sale				$ 37
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale		102				102			3,756
Transfer of loans held-for-sale to held-for-investment			$ 538
Valuation allowance		16				16			7
Consumer loans | Disposal Group, Disposed of by Sale, Not Discontinued Operations | Retail Branches Sold
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sales of loans held for sale				2,102
Consumer loans | Exit of Mass Market Retail Banking Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sales of loans held for sale				904
Loss on sale of loans				(35)
Loans Transferred From Portfolio Loans to Held For Sale | Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale		329				329			359
Residential mortgages | Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale		7				7			3,082
Residential mortgages | Consumer loans | Disposal Group, Disposed of by Sale, Not Discontinued Operations | Retail Branches Sold
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sales of loans held for sale				1,665
Residential mortgages | Consumer loans | Exit of Mass Market Retail Banking Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sales of loans held for sale				865
Home equity mortgages | Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale		0				0			275
Home equity mortgages | Consumer loans | Disposal Group, Disposed of by Sale, Not Discontinued Operations | Retail Branches Sold
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sales of loans held for sale				185
Home equity mortgages | Consumer loans | Exit of Mass Market Retail Banking Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sales of loans held for sale				39
Credit cards | Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale		8				8			195
Credit cards | Consumer loans | Disposal Group, Disposed of by Sale, Not Discontinued Operations | Retail Branches Sold
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sales of loans held for sale				168
Credit cards | Consumer loans | Exit of Mass Market Retail Banking Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale		8				8
Student loans held for sale | Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, designated under fair value option		21				21
Other consumer | Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale		87				87			204
Other consumer | Consumer loans | Disposal Group, Disposed of by Sale, Not Discontinued Operations | Retail Branches Sold
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sales of loans held for sale				$ 84
Other consumer | Consumer loans | Exit of Mass Market Retail Banking Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale		87				87
Global banking | Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale		444				444			$ 338
Global banking | Commercial loans | 2020 - 2021 Restructuring Plan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans sold		0				44
Loss on sale of loans		(18)				(21)
Other Income (Loss)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revenue (losses) associated with the economic hedging program		0			(1)	7	(2)
Other Income (Loss) | Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded lower of amortized cost or fair value adjustment		13			(1)	10	4
Other Income (Loss) | Consumer loans | Exit of Mass Market Retail Banking Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded lower of amortized cost or fair value adjustment		$ 3			$ 1	$ 11	$ 1

[1] The following table summarizes assets and liabilities related to our consolidated variable interest entities ("VIEs") at September 30, 2022 and December 31, 2021. Assets and liabilities exclude intercompany balances that eliminate in consolidation. See Note 17, "Variable Interest Entities," for additional information. September 30, 2022December 31, 2021(in millions)AssetsLoans$127 $46 Other assets44 55 Total assets$171 $101 LiabilitiesInterest, taxes and other liabilities$26 $9 Total liabilities$26 $9