Derivative Instruments - Change in Our Unrealized Gain on Derivative Instruments in AOCI (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Change in our unrealized gain on derivative instruments in accumulated OCI
Balance as of beginning-of-year	$ 10,906
Balance as of end-of-period	10,212	$ 8,193
Interest rate contracts | Net Investment Income | Qualifying Hedges
Change in our unrealized gain on derivative instruments in accumulated OCI
Hedged items	(1)	11
Derivatives designated as hedging instruments	1	(11)
Interest rate contracts | Interest and Debt Expense | Qualifying Hedges
Change in our unrealized gain on derivative instruments in accumulated OCI
Hedged items	(2)	(15)
Derivatives designated as hedging instruments	2	15
Interest rate contracts | Realized Gain (Loss) | Qualifying Hedges
Change in our unrealized gain on derivative instruments in accumulated OCI
Hedged items	0	0
Derivatives designated as hedging instruments	0	0
Foreign currency contracts | Net Investment Income | Qualifying Hedges
Change in our unrealized gain on derivative instruments in accumulated OCI
Hedged items	(1)	1
Derivatives designated as hedging instruments	1	(1)
Foreign currency contracts | Interest and Debt Expense | Qualifying Hedges
Change in our unrealized gain on derivative instruments in accumulated OCI
Hedged items	0	0
Derivatives designated as hedging instruments	0	0
Foreign currency contracts | Realized Gain (Loss) | Qualifying Hedges
Change in our unrealized gain on derivative instruments in accumulated OCI
Hedged items	0	0
Derivatives designated as hedging instruments	0	0
Unrealized Gain (Loss) on Derivative Instruments
Change in our unrealized gain on derivative instruments in accumulated OCI
Balance as of beginning-of-year	450	638
Income tax benefit (expense)	(30)	(4)
Reclassification adjustment for gains (losses) included in net income (loss)	18	21
Income tax benefit (expense)	(4)	(4)
Balance as of end-of-period	544	637
Unrealized Gain (Loss) on Derivative Instruments | Interest rate contracts | Interest and Debt Expense
Change in our unrealized gain on derivative instruments in accumulated OCI
Reclassification adjustment for gains (losses) included in net income (loss)	2	3
Unrealized Gain (Loss) on Derivative Instruments | Foreign currency contracts | Net Investment Income
Change in our unrealized gain on derivative instruments in accumulated OCI
Reclassification adjustment for gains (losses) included in net income (loss)	15	15
Unrealized Gain (Loss) on Derivative Instruments | Foreign currency contracts | Realized Gain (Loss)
Change in our unrealized gain on derivative instruments in accumulated OCI
Reclassification adjustment for gains (losses) included in net income (loss)	1	3
Unrealized holding gains (losses) arising during the period - cash flow hedges
Change in our unrealized gain on derivative instruments in accumulated OCI
Changes arising during the year	62	173
Unrealized holding gains (losses) arising during the period - cash flow hedges | Interest rate contracts
Change in our unrealized gain on derivative instruments in accumulated OCI
Changes arising during the year	(7)	5
Unrealized holding gains (losses) arising during the period - cash flow hedges | Foreign currency contracts
Change in our unrealized gain on derivative instruments in accumulated OCI
Changes arising during the year	69	168
Change in foreign currency exchange rate adjustment
Change in our unrealized gain on derivative instruments in accumulated OCI
Changes arising during the year	$ 76	$ (153)