Segment Information - Reconciliation of Revenue from Segments to Consolidated (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Operating revenues	$ 4,167	$ 4,126
Revenue adjustments from annuity and life insurance product features	170	169
Credit loss-related adjustments	(28)	(1)
Investment gains (losses)	37	(56)
Changes in the fair value of reinsurance-related embedded derivatives, trading securities and certain mortgage loans	(177)	48
GLB rider fees ceded to LNBAR	(232)	(230)
Total revenues	3,937	4,056
Other Operations
Segment Reporting Information [Line Items]
Operating revenues	42	26
Revenue adjustments from annuity and life insurance product features	0	0
Credit loss-related adjustments	(8)	(1)
Investment gains (losses)	15	(66)
Changes in the fair value of reinsurance-related embedded derivatives, trading securities and certain mortgage loans	(12)	1
GLB rider fees ceded to LNBAR	0	0
Total revenues	37	(40)
Annuities | Operating Segments
Segment Reporting Information [Line Items]
Operating revenues	1,118	1,178
Revenue adjustments from annuity and life insurance product features	152	302
Credit loss-related adjustments	(17)	(3)
Investment gains (losses)	(2)	21
Changes in the fair value of reinsurance-related embedded derivatives, trading securities and certain mortgage loans	(93)	34
GLB rider fees ceded to LNBAR	(232)	(230)
Total revenues	926	1,302
Life Insurance | Operating Segments
Segment Reporting Information [Line Items]
Operating revenues	1,211	1,181
Revenue adjustments from annuity and life insurance product features	18	(133)
Credit loss-related adjustments	1	3
Investment gains (losses)	26	(6)
Changes in the fair value of reinsurance-related embedded derivatives, trading securities and certain mortgage loans	(36)	13
GLB rider fees ceded to LNBAR	0	0
Total revenues	1,220	1,058
Group Protection | Operating Segments
Segment Reporting Information [Line Items]
Operating revenues	1,472	1,424
Revenue adjustments from annuity and life insurance product features	0	0
Credit loss-related adjustments	(2)	0
Investment gains (losses)	0	0
Changes in the fair value of reinsurance-related embedded derivatives, trading securities and certain mortgage loans	(36)	0
GLB rider fees ceded to LNBAR	0	0
Total revenues	1,434	1,424
Retirement Plan Services | Operating Segments
Segment Reporting Information [Line Items]
Operating revenues	324	317
Revenue adjustments from annuity and life insurance product features	0	0
Credit loss-related adjustments	(2)	0
Investment gains (losses)	(2)	(5)
Changes in the fair value of reinsurance-related embedded derivatives, trading securities and certain mortgage loans	0	0
GLB rider fees ceded to LNBAR	0	0
Total revenues	$ 320	$ 312