Capital contribution to private equity funds.

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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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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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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		6 Months Ended		12 Months Ended
	Jun. 30, 2021 USD ($) investment	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) investment	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Variable Interest Entity
Assets	$ 205,390		$ 205,390		$ 204,680
LLCs designed for the purpose of purchasing pools of residual interests in leases
Variable Interest Entity
Number of co-investments \| investment	3		3
Ownership percentage (more than)	50.00%		50.00%
Lower limit
Variable Interest Entity
Unfunded commitments, year expected to be funded			2021
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			$ 1,400		1,200
Variable Interest Entity, Not Primary Beneficiary \| CDC investments
Variable Interest Entity
Assets	$ 1,668		1,668		1,546
Variable Interest Entity, Not Primary Beneficiary \| CDC investments \| Qualified Affordable Housing Tax Credits
Variable Interest Entity
Assets	1,400		1,400		1,300
Unfunded commitments in qualifying LIHTC investments	514		514		478
Variable Interest Entity, Not Primary Beneficiary \| Private equity investments
Variable Interest Entity
Assets	117		117		117
Unfunded commitment amounts			91		$ 83
Capital contribution to private equity investments	$ 6	$ 1	$ 7	$ 5