Carryover basis of shares.

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Letters Credit Issued Related Variable Rate Demand Notes.

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Outstanding repurchase demand inventory.

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Percentage Of Letter Of Credit.

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Repurchase demand request.

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Repurchased Outstanding Principal.

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Reserve For Unfunded Credit Commitments.

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Stock Received InInitial Public Offering Shares.

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Total Variable Rate Demand Notes.

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No definition available.

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Carrying value as of the balance sheet date of the sum of the obligations to contract holders to provide to them an agreed upon rate of return pursuant to the terms of the underlying contract. These contracts represent lending by the contract holders to the entity in return for a guaranteed (primarily fixed) interest rate until maturity, unless called earlier if the contracts provide that option to the contract holders (usually institutions). There is little or no insurance risk for the entity.

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The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of valuation and qualifying accounts and reserves.

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Commitments, Contingent Liabilities and Guarantees - Additional Information (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Sep. 30, 2019	Jun. 30, 2018	Sep. 30, 2014	Sep. 30, 2012	Mar. 31, 2012	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010	Dec. 31, 2008
Loss Contingencies
Letters of credit	$ 1,953	$ 1,982
Margin account balance held by the brokerage clearing agent	20	14
Visa
Loss Contingencies
Fair value of mortgage representation and warranty provisions	214	201
Visa IPO, shares of Visa's Class B common stock received											10.1
Visa Class B shares carryover basis											$ 0
Escrow deposit	250		$ 300	$ 600	$ 450	$ 150	$ 1,565	$ 400	$ 800	$ 500	$ 3,000
Residential mortgage loans
Loss Contingencies
Outstanding balances on residential mortgage loans sold with representation and warranty provisions	9	8
Fair value of mortgage representation and warranty provisions	12
Repurchased outstanding principal	42	25
Repurchase demand request	64	32
Outstanding repurchase demand inventory	18	5
Secured Debt
Loss Contingencies
Fully and unconditionally guaranteed certain long-term borrowing obligations issued by wholly-owned issuing trust entities	62	62
Standby Letters of Credit
Loss Contingencies
Reserve for unfunded commitments	$ 24	$ 27
Standby letters of credit as a percentage of total letters of credit	99.00%	99.00%
Standby Letters of Credit \| Secured Debt
Loss Contingencies
Standby letters of credit as a percentage of total letters of credit	71.00%	68.00%
Variable Rate Demand Note
Loss Contingencies
Total variable rate demand notes	$ 464	$ 385
Letters of credit issued related to variable rate demand notes	118	142
Variable Rate Demand Note \| Trading Securities
Loss Contingencies
Total variable rate demand notes	1	0
Other Liabilities
Loss Contingencies
Reserve for unfunded commitments	$ 182	$ 172