Shares and Stockholders' Equity - Schedule of Reclassifications Out of AOCI (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment income	$ 1,439	$ 1,309	$ 4,152	$ 3,775
Realized gain (loss)	(330)	(571)	(740)	(345)
Benefits	547	1,572	3,925	583
Income (loss) before taxes	308	(795)	474	956
Income tax benefit (expense)	(33)	195	(11)	(138)
Net income (loss)	$ 275	$ (600)	463	818
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gain (Loss) on Fixed Maturity AFS Securities and Certain Other Investments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Realized gain (loss)			(17)	(15)
Benefits			9	6
Income (loss) before taxes			(8)	(9)
Income tax benefit (expense)			1	2
Net income (loss)			(7)	(7)
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gain (Loss) on Derivative Instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Realized gain (loss)			2	1
Income (loss) before taxes			44	40
Income tax benefit (expense)			(9)	(8)
Net income (loss)			35	32
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gain (Loss) on Derivative Instruments | Interest rate contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment income			0	(2)
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gain (Loss) on Derivative Instruments | Foreign currency contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment income			$ 42	$ 41