Deferred Policy Acquisition Costs, Deferred Sales Inducements and Value of Business Acquired - Schedule of Rollforward of Deferred Acquisition Costs and Value of Business Acquired (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
DAC
Balance, beginning of period	$ 1,801	$ 817	$ 1,325	$ 572
Additions	444	374	1,165	857
Amortization	(129)	(117)	(374)	(355)
Net change	315	257	791	502
Balance, end of period	2,116	1,074	2,116	1,074
DSI
Balance, beginning of period	723	103	393	8
Additions	234	141	583	235
Amortization	(14)	(4)	(33)	(3)
Net change	220	137	550	232
Balance, end of period	943	240	943	240
VOBA
Balance, beginning of period	8,527	7,435	8,913	364
Acquisition from business combinations		45		7,239
Amortization	(202)	(168)	(588)	(291)
Other		(250)		(250)
Net change	(202)	(373)	(588)	6,698
Balance, end of period	8,325	7,062	8,325	7,062
Total DAC, DSI, and VOBA Asset	11,384	8,376	11,384	8,376	$ 10,631
Annuities
DAC
Balance, beginning of period	1,350	406	887	190
Additions	324	242	834	472
Amortization	(33)	(8)	(80)	(22)
Net change	291	234	754	450
Balance, end of period	1,641	640	1,641	640
DSI
Balance, beginning of period	723	103	393	8
Additions	234	141	583	235
Amortization	(14)	(4)	(33)	(3)
Net change	220	137	550	232
Balance, end of period	943	240	943	240
VOBA
Balance, beginning of period	8,457	7,126	8,838	39
Acquisition from business combinations		45		7,239
Amortization	(200)	(162)	(581)	(269)
Other		0		0
Net change	(200)	(117)	(581)	6,970
Balance, end of period	8,257	7,009	8,257	7,009
Total DAC, DSI, and VOBA Asset	10,841	7,889	10,841	7,889
Property and Casualty
DAC
Balance, beginning of period	116	140	132	158
Additions	75	106	241	302
Amortization	(82)	(99)	(264)	(313)
Net change	(7)	7	(23)	(11)
Balance, end of period	109	147	109	147
DSI
Balance, beginning of period	0	0	0	0
Additions	0	0	0	0
Amortization	0	0	0	0
Net change	0	0	0	0
Balance, end of period	0	0	0	0
VOBA
Balance, beginning of period	7	16	10	20
Acquisition from business combinations		0		0
Amortization	(1)	3	(4)	(1)
Other		0		0
Net change	(1)	3	(4)	(1)
Balance, end of period	6	19	6	19
Total DAC, DSI, and VOBA Asset	115	166	115	166
Life Insurance
DAC
Balance, beginning of period	335	271	306	224
Additions	45	26	90	83
Amortization	(14)	(10)	(30)	(20)
Net change	31	16	60	63
Balance, end of period	366	287	366	287
DSI
Balance, beginning of period	0	0	0	0
Additions	0	0	0	0
Amortization	0	0	0	0
Net change	0	0	0	0
Balance, end of period	0	0	0	0
VOBA
Balance, beginning of period	63	293	65	305
Acquisition from business combinations		0		0
Amortization	(1)	(9)	(3)	(21)
Other		(250)		(250)
Net change	(1)	(259)	(3)	(271)
Balance, end of period	62	34	62	34
Total DAC, DSI, and VOBA Asset	$ 428	$ 321	$ 428	$ 321

American National Group Inc. 10-Q