Derivative Instruments - Change in Our Unrealized Gain on Derivative Instruments in AOCI (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Change in our unrealized gain on derivative instruments in accumulated OCI
Balance as of beginning-of-year	$ 6,893
Balance as of end-of-period	7,546	$ 6,732
Unrealized Gain (Loss) on Derivative Instruments
Change in our unrealized gain on derivative instruments in accumulated OCI
Balance as of beginning-of-year	375	388
Income tax benefit (expense)	(35)	(15)
Reclassification adjustment for gains (losses) included in net income (loss)	24	22
Income tax benefit (expense)	(5)	(5)
Balance as of end-of-period	486	423
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)	9	6
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	14
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)	0	2
Unrealized holding gains (losses) arising during the year
Change in our unrealized gain on derivative instruments in accumulated OCI
Changes arising during the year	64	134
Unrealized holding gains (losses) arising during the year | Interest rate contracts
Change in our unrealized gain on derivative instruments in accumulated OCI
Changes arising during the year	89	58
Unrealized holding gains (losses) arising during the year | Foreign currency contracts
Change in our unrealized gain on derivative instruments in accumulated OCI
Changes arising during the year	(25)	76
Change in foreign currency exchange rate adjustment
Change in our unrealized gain on derivative instruments in accumulated OCI
Changes arising during the year	$ 101	$ (67)