Segment Information - Reconciliation of Revenue from Segments to Consolidated (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Segment Reporting Information [Line Items]
Operating revenues	$ 15,751	$ 12,078	$ 15,059
Revenue adjustments from annuity and life insurance product features	854	922	99
Credit loss-related adjustments	(134)	(152)	(74)
Investment gains (losses)	(36)	(311)	(4,080)
Changes in the fair value of reinsurance-related embedded derivatives, trading securities and certain mortgage loans	(452)	203	(22)
GLB rider fees ceded to LNBAR	(941)	(933)	(923)
Gains (losses) on other non-financial assets - sale of subsidiaries/businesses	(14)	481
Total revenues	15,028	12,288	10,059
Other Operations
Segment Reporting Information [Line Items]
Operating revenues	185	149	(778)
Revenue adjustments from annuity and life insurance product features	0	0	0
Credit loss-related adjustments	(70)	(35)	(6)
Investment gains (losses)	(102)	(229)	(94)
Changes in the fair value of reinsurance-related embedded derivatives, trading securities and certain mortgage loans	(24)	22	(1)
GLB rider fees ceded to LNBAR	0	0	0
Gains (losses) on other non-financial assets - sale of subsidiaries/businesses	(14)	481
Total revenues	(25)	388	(879)
Annuities \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenues	4,568	4,549	2,625
Revenue adjustments from annuity and life insurance product features	955	1,175	509
Credit loss-related adjustments	(26)	(71)	(14)
Investment gains (losses)	(3)	(13)	(78)
Changes in the fair value of reinsurance-related embedded derivatives, trading securities and certain mortgage loans	(231)	104	(76)
GLB rider fees ceded to LNBAR	(940)	(932)	(922)
Gains (losses) on other non-financial assets - sale of subsidiaries/businesses	0	0
Total revenues	4,323	4,812	2,044
Life Insurance \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenues	4,916	4,988	6,362
Revenue adjustments from annuity and life insurance product features	(101)	(253)	(411)
Credit loss-related adjustments	(17)	(10)	(49)
Investment gains (losses)	73	9	(3,867)
Changes in the fair value of reinsurance-related embedded derivatives, trading securities and certain mortgage loans	(120)	87	55
GLB rider fees ceded to LNBAR	0	0	0
Gains (losses) on other non-financial assets - sale of subsidiaries/businesses	0	0
Total revenues	4,751	4,821	2,090
Group Protection \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenues	4,745	1,088	5,560
Revenue adjustments from annuity and life insurance product features	0	0	0
Credit loss-related adjustments	(3)	(4)	(4)
Investment gains (losses)	0	(8)	(6)
Changes in the fair value of reinsurance-related embedded derivatives, trading securities and certain mortgage loans	(77)	(10)	0
GLB rider fees ceded to LNBAR	0	0	0
Gains (losses) on other non-financial assets - sale of subsidiaries/businesses	0	0
Total revenues	4,665	1,066	5,550
Retirement Plan Services \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenues	1,337	1,304	1,290
Revenue adjustments from annuity and life insurance product features	0	0	1
Credit loss-related adjustments	(18)	(32)	(1)
Investment gains (losses)	(4)	(70)	(35)
Changes in the fair value of reinsurance-related embedded derivatives, trading securities and certain mortgage loans	0	0	0
GLB rider fees ceded to LNBAR	(1)	(1)	(1)
Gains (losses) on other non-financial assets - sale of subsidiaries/businesses	0	0
Total revenues	$ 1,314	$ 1,201	$ 1,254

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