Derivatives and Hedge Accounting - Notional Amounts and Fair Values of Derivative Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Gross Derivative Assets
Notional Amount	$ 2,975	$ 4,896
Fair Value	423	624
Counterparty netting	(207)	(270)
Cash Collateral	(199)	(304)
Derivative assets	17	50
Gross Derivative Liabilities
Notional Amount	5,089	3,702
Fair Value	529	622
Counterparty netting	(207)	(270)
Cash Collateral	(264)	(201)
Total derivative liabilities on consolidated balance sheet	58	151
Bifurcated embedded derivatives assets, fair value	3,100	3,200
Bifurcated embedded derivative liabilities, fair value	0	0
Derivatives designated as hedging instruments | Foreign exchange contracts
Gross Derivative Assets
Notional Amount	868	879
Fair Value	35	66
Gross Derivative Liabilities
Notional Amount	883	906
Fair Value	59	109
Derivatives not designated as hedging instruments | Interest rate contracts
Gross Derivative Assets
Notional Amount	943	841
Fair Value	265	277
Gross Derivative Liabilities
Notional Amount	1,022	913
Fair Value	296	304
Derivatives not designated as hedging instruments | Foreign exchange contracts
Gross Derivative Assets
Notional Amount	1,104	3,095
Fair Value	83	230
Gross Derivative Liabilities
Notional Amount	3,119	1,707
Fair Value	134	158
Derivatives not designated as hedging instruments | Equity contracts
Gross Derivative Assets
Notional Amount	18	29
Fair Value	14	20
Gross Derivative Liabilities
Notional Amount	18	29
Fair Value	14	20
Derivatives not designated as hedging instruments | Credit contracts
Gross Derivative Assets
Notional Amount	42	52
Fair Value	26	31
Gross Derivative Liabilities
Notional Amount	47	147
Fair Value	26	31
Derivatives not designated as hedging instruments | Credit contracts | CDS
Gross Derivative Liabilities
Notional Amount	38	48
Fair Value	$ 26	$ 30