Derivatives - Derivative Assets and Collateral Received (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Gross amounts of recognized assets	$ 479	$ 765
Derivative liabilities available for offset	0	0
Net amount	479	765
Derivative liabilities available for offset	(43)	(21)
Collateral received	(236)	(347)
Net amount	200	397
Derivative assets not subject to master netting agreements	3	4
Derivatives, interest rate contracts
Derivative [Line Items]
Gross amounts of recognized assets	453	702
Derivative liabilities available for offset	0	0
Net amount	453	702
Derivative liabilities available for offset	(29)	(7)
Collateral received	(227)	(327)
Net amount	197	368
Forward contracts
Derivative [Line Items]
Gross amounts of recognized assets	26	63
Derivative liabilities available for offset	0	0
Net amount	26	63
Derivative liabilities available for offset	(14)	(14)
Collateral received	(9)	(20)
Net amount	$ 3	$ 29

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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