Derivative Instruments - Change in Our Unrealized Gain on Derivative Instruments in AOCI (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Change in our unrealized gain on derivative instruments in accumulated OCI
Balance as of beginning-of-year	$ 8,269
Balance as of end-of-period	8,193	$ 7,546
Unrealized Gain (Loss) on Derivative Instruments
Change in our unrealized gain on derivative instruments in accumulated OCI
Balance as of beginning-of-year	638	375
Income tax benefit (expense)	(4)	(35)
Reclassification adjustment for gains (losses) included in net income (loss)	21	24
Income tax benefit (expense)	(4)	(5)
Balance as of end-of-period	637	486
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)	3	9
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)	3	0
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	173	64
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	5	89
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	168	(25)
Change in foreign currency exchange rate adjustment
Change in our unrealized gain on derivative instruments in accumulated OCI
Changes arising during the year	$ (153)	$ 101