Derivative Instruments - Change in Our Unrealized Gain on Derivative Instruments in AOCI (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024
Change in our unrealized gain on derivative instruments in accumulated OCI
Balance as of beginning-of-year	$ 10,512
Balance as of end-of-period	11,514	$ 11,029
Unrealized Gain (Loss) on Derivative Instruments
Change in our unrealized gain on derivative instruments in accumulated OCI
Balance as of beginning-of-year	402	249
Income tax benefit (expense)	60	(35)
Reclassification adjustment for gains (losses) included in net income (loss)	31	27
Income tax benefit (expense)	(7)	(6)
Balance as of end-of-period	155	356
Unrealized Gain (Loss) on Derivative Instruments \| Interest rate 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)	1	(1)
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)	27	29
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	(1)
Unrealized holding gains (losses)
Change in our unrealized gain on derivative instruments in accumulated OCI
OCI before reclassification	191	46
Unrealized holding gains (losses) \| Interest rate contracts
Change in our unrealized gain on derivative instruments in accumulated OCI
OCI before reclassification	22	18
Unrealized holding gains (losses) \| Foreign currency contracts
Change in our unrealized gain on derivative instruments in accumulated OCI
OCI before reclassification	169	28
Change in foreign currency exchange rate adjustment
Change in our unrealized gain on derivative instruments in accumulated OCI
OCI before reclassification	$ (474)	$ 117

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