Capital contribution to private equity funds.

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- Definition

Number Of Investments

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Year in which contingent commitments to qualified affordable housing project investments are expected to be paid, in YYYY format.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at stated interest rates.

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Amount of commitment or contingent commitments to qualified affordable housing project investments.

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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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Variable Interest Entities - Additional Information (Details) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2022 USD ($) investment	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Variable Interest Entity
Assets	$ 211,459		$ 211,116
LLCs designed for the purpose of purchasing pools of residual interests in leases
Variable Interest Entity
Number of co-investments \| investment	3
Ownership percentage (more than)	50.00%
Lower limit
Variable Interest Entity
Unfunded commitments, year expected to be funded	2022
Upper limit
Variable Interest Entity
Unfunded commitments, year expected to be funded	2039
Variable Interest Entity, Not Primary Beneficiary \| Loans provided to VIEs
Variable Interest Entity
Unfunded commitment amounts	$ 1,500		1,500
Variable Interest Entity, Not Primary Beneficiary \| CDC investments
Variable Interest Entity
Assets	1,683		1,705
Variable Interest Entity, Not Primary Beneficiary \| CDC investments \| Qualified Affordable Housing Tax Credits
Variable Interest Entity
Assets	1,400		1,400
Unfunded commitments in qualifying LIHTC investments	521		573
Variable Interest Entity, Not Primary Beneficiary \| Private equity investments
Variable Interest Entity
Assets	143		133
Unfunded commitment amounts	135		$ 124
Capital contribution to private equity investments	$ 9	$ 2