Accumulated Other Comprehensive Income Loss - AOCI Rollforward (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			$ 18,979
OCI, net of tax	$ (1,472)	$ 381	(1,786)	$ 883
Ending balance	18,873	18,450	18,873	18,450
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(942)	(1,029)	(641)	(1,539)
OCI before reclassifications	(1,819)	451	(2,238)	1,061
Amounts reclassified from AOCI	22	21	60	57
OCI, before tax	(1,797)	472	(2,178)	1,118
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	377	(99)	457	(235)
OCI, net of tax	(1,420)	373	(1,721)	883
Ending balance	(2,362)	(656)	(2,362)	(656)
AOCI, Gain (Loss), Debt Securities, Available-for-sale, with Allowance for Credit Loss, Parent
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(3)	(5)	(3)	(6)
OCI before reclassifications	0	3	0	4
Amounts reclassified from AOCI	0	0	0	0
OCI, before tax	0	3	0	4
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	0	(1)	0	(1)
OCI, net of tax	0	2	0	3
Ending balance	(3)	(3)	(3)	(3)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(16)	6	16	40
OCI before reclassifications	(91)	14	(124)	(22)
Amounts reclassified from AOCI	(5)	(3)	(13)	(10)
OCI, before tax	(96)	11	(137)	(32)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	20	(2)	29	7
OCI, net of tax	(76)	9	(108)	(25)
Ending balance	(92)	15	(92)	15
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	42	45	42	29
OCI before reclassifications	0	(3)	0	18
Amounts reclassified from AOCI	0	0	0	0
OCI, before tax	0	(3)	0	18
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	0	1	0	(4)
OCI, net of tax	0	(2)	0	14
Ending balance	42	43	42	43
AOCI, Liability for Future Policy Benefit, Parent
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	26	29	24	33
OCI before reclassifications	19	(9)	22	(14)
Amounts reclassified from AOCI	0	0	0	0
OCI, before tax	19	(9)	22	(14)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(4)	2	(5)	3
OCI, net of tax	15	(7)	17	(11)
Ending balance	41	22	41	22
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(1,478)	(1,430)	(1,495)	(1,443)
OCI before reclassifications	0	0	1	0
Amounts reclassified from AOCI	11	8	32	24
OCI, before tax	11	8	33	24
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(2)	(2)	(7)	(5)
OCI, net of tax	9	6	26	19
Ending balance	(1,469)	(1,424)	(1,469)	(1,424)
AOCI Attributable to Parent [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(2,371)	(2,384)	(2,057)	(2,886)
OCI before reclassifications	(1,891)	456	(2,339)	1,047
Amounts reclassified from AOCI	28	26	79	71
OCI, before tax	(1,863)	482	(2,260)	1,118
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	391	(101)	474	(235)
OCI, net of tax	(1,472)	381	(1,786)	883
Ending balance	$ (3,843)	$ (2,003)	$ (3,843)	$ (2,003)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount before tax and reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

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