Variable Interest Entities - Narrative (Details) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2022 USD ($) investment	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) investment	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Variable Interest Entity
Assets	$ 206,782		$ 206,782		$ 211,116
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%
Variable Interest Entity, Not Primary Beneficiary | Loans provided to VIEs
Variable Interest Entity
Unfunded commitment amounts			$ 1,700		1,500
Variable Interest Entity, Not Primary Beneficiary | CDC investments
Variable Interest Entity
Assets	$ 1,730		1,730		1,705
Risk retention interests	1,730		1,730		1,705
Variable Interest Entity, Not Primary Beneficiary | CDC investments | Qualified Affordable Housing Tax Credits
Variable Interest Entity
Assets	1,500		1,500		1,400
Unfunded commitments in qualifying LIHTC investments	574		$ 574		573
Variable Interest Entity, Not Primary Beneficiary | CDC investments | Qualified Affordable Housing Tax Credits | Lower limit
Variable Interest Entity
Unfunded commitments, year expected to be funded			2022
Variable Interest Entity, Not Primary Beneficiary | CDC investments | Qualified Affordable Housing Tax Credits | Upper limit
Variable Interest Entity
Unfunded commitments, year expected to be funded			2039
Variable Interest Entity, Not Primary Beneficiary | Private equity investments
Variable Interest Entity
Assets	165		$ 165		133
Unfunded commitment amounts			136		124
Capital contribution to private equity investments	12	$ 6	21	$ 7
Risk retention interests	301		301		$ 257
Variable Interest Entity, Not Primary Beneficiary | Solar loan securitizations
Variable Interest Entity
Assets	11		11
Risk retention interests	$ 11		$ 11