Segment Information - Reconciliation of Income (Loss) from Operations by Segment to Consolidated Net Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Operating revenues		$ 12,078	$ 15,059	$ 17,139
Interest credited		3,160	3,202	2,860
Commissions		2,076	2,082	2,201
General and administrative expenses		2,539	2,580	2,367
Interest and debt expense		185	190	137
Total federal income tax expense (benefit)		452	(673)	(437)
Reconciliation of total income (loss) from operations to net income (loss):
Net annuity product features, pre-tax		2,085	1,640	528
Net life insurance product features, pre-tax		(237)	187	26
Credit loss-related adjustments, pre-tax		(152)	(74)	(129)
Investment gains (losses), pre-tax		(311)	(4,080)	19
Changes in the fair value of reinsurance-related embedded derivatives, trading securities and certain mortgage loans, pre-tax		203	(22)	588
GLB rider fees ceded to LNBAR, pre-tax		(933)	(923)	(932)
Gains (losses) on other non-financial assets – sale of subsidiaries/businesses, pre-tax		481
Impairment of intangibles				(634)
Other items, pre-tax		(144)	(163)	(129)
Certain legal accruals, before tax	$ (12)	(18)	(120)	(147)
Severance expense for workforce realignment, before tax		(74)	(7)
Transaction and integration costs for acquisitions or divestiture, before tax		(29)	(34)
Deferred compensation mark-to-market adjustment, before tax		(11)	(2)	18
Income tax benefit (expense) related to the above pre-tax items		(214)	735	7
Net income (loss)		2,130	(1,788)	(1,675)
Operating Segments and Corporate Non Segment
Segment Reporting Information [Line Items]
Operating revenues		12,078	15,059	17,139
Benefits and policyholder liability remeasurement (gain) loss		2,096	5,458	10,640
Interest credited		3,160	3,202	2,860
Commissions		2,076	2,082	2,201
General and administrative expenses		2,441	2,459	2,239
Interest and debt expense		185	190	137
Other		522	711	511
Total operating expenses		10,480	14,102	18,588
Total federal income tax expense (benefit)		246	45	(430)
Total income (loss) from operations		1,352	912	(1,019)
Other Operations
Segment Reporting Information [Line Items]
Operating revenues		149	(778)	133
Benefits and policyholder liability remeasurement (gain) loss		6	(871)	69
Interest credited		32	36	39
Commissions		0	0	0
General and administrative expenses		182	193	212
Interest and debt expense		185	190	137
Other		3	4	5
Total operating expenses		408	(448)	462
Total federal income tax expense (benefit)		(49)	(76)	(57)
Total income (loss) from operations		(210)	(254)	(272)
Annuities | Operating Segments
Segment Reporting Information [Line Items]
Operating revenues		4,549	2,625	4,102
Benefits and policyholder liability remeasurement (gain) loss		143	(1,506)	252
Interest credited		1,538	1,254	896
Commissions		1,115	972	1,020
General and administrative expenses		495	469	405
Interest and debt expense		0	0	0
Other		156	517	453
Total operating expenses		3,447	1,706	3,026
Total federal income tax expense (benefit)		172	79	128
Total income (loss) from operations		930	840	948
Life Insurance | Operating Segments
Segment Reporting Information [Line Items]
Operating revenues		4,988	6,362	6,344
Benefits and policyholder liability remeasurement (gain) loss		2,732	4,103	6,388
Interest credited		909	1,242	1,291
Commissions		442	577	708
General and administrative expenses		554	610	552
Interest and debt expense		0	0	0
Other		194	18	(118)
Total operating expenses		4,831	6,550	8,821
Total federal income tax expense (benefit)		13	(62)	(544)
Total income (loss) from operations		144	(126)	(1,933)
Group Protection | Operating Segments
Segment Reporting Information [Line Items]
Operating revenues		1,088	5,560	5,303
Benefits and policyholder liability remeasurement (gain) loss		(785)	3,732	3,931
Interest credited		6	5	5
Commissions		415	446	394
General and administrative expenses		870	846	766
Interest and debt expense		0	0	0
Other		153	155	156
Total operating expenses		659	5,184	5,252
Total federal income tax expense (benefit)		90	79	11
Total income (loss) from operations		339	297	40
Retirement Plan Services | Operating Segments
Segment Reporting Information [Line Items]
Operating revenues		1,304	1,290	1,257
Benefits and policyholder liability remeasurement (gain) loss		0	0	0
Interest credited		675	665	629
Commissions		104	87	79
General and administrative expenses		340	341	304
Interest and debt expense		0	0	0
Other		16	17	15
Total operating expenses		1,135	1,110	1,027
Total federal income tax expense (benefit)		20	25	32
Total income (loss) from operations		$ 149	$ 155	$ 198