Policyholders' Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Additional Liability, Long-Duration Insurance [Roll Forward]
Balance, beginning of period	$ 69,628,318
Transfer to (from) Policyholder Account Balance (to) from Separate Account	113,985	$ 78,080
Unearned revenue reserve	4,576,066	3,908,497
Other	108,240	103,851
Total Policyholders' account balance	$ 71,559,381	$ 57,764,158
Weighted-average crediting rate	2.21%	2.44%
Net amount at risk	$ 350,942,454	$ 327,231,579
Cash surrender value	62,734,038	48,856,565
Total
Additional Liability, Long-Duration Insurance [Roll Forward]
Balance, beginning of period	65,105,807	49,142,691
Deposits	3,930,982	3,708,020
Interest credited(4)	364,898	313,520
Policy charges	(486,573)	(457,032)
Surrenders and withdrawals	(639,085)	(483,591)
Benefit payments	(62,503)	(35,661)
Transfer to (from) Policyholder Account Balance (to) from Separate Account	113,985	78,080
Change in market value and other adjustments	(1,452,436)	1,485,783
Balance, end of period	66,875,075	53,751,810
Fixed Annuities
Additional Liability, Long-Duration Insurance [Roll Forward]
Balance, beginning of period	11,197,337	6,164,313
Deposits	1,118,299	1,553,852
Interest credited(4)	70,850	43,517
Policy charges		2,208
Policy charges	(11,409)
Surrenders and withdrawals	(157,652)	(103,696)
Benefit payments	(26,429)	(12,879)
Transfer to (from) Policyholder Account Balance (to) from Separate Account	0	0
Change in market value and other adjustments	(49,620)	88,291
Balance, end of period	12,141,376	7,735,606
Total Policyholders' account balance	$ 5,528,553	$ 3,148,584
Weighted-average crediting rate	2.43%	2.50%
Net amount at risk	$ 1,458	$ 18
Cash surrender value	10,896,794	6,674,346
Variable Annuity
Additional Liability, Long-Duration Insurance [Roll Forward]
Balance, beginning of period	33,217,331	22,810,665
Deposits	2,229,851	1,624,956
Interest credited(4)	148,597	131,944
Policy charges	(15,546)	(3,702)
Surrenders and withdrawals	(250,968)	(179,988)
Benefit payments	(4,163)	(4,926)
Transfer to (from) Policyholder Account Balance (to) from Separate Account	23,157	(6,723)
Change in market value and other adjustments	(1,412,076)	1,360,323
Balance, end of period	33,936,183	25,732,549
Total Policyholders' account balance	$ 2,454,759	$ 2,821,316
Weighted-average crediting rate	1.77%	2.17%
Net amount at risk	$ 0	$ 0
Cash surrender value	32,338,553	23,282,269
Variable/Universal Life
Additional Liability, Long-Duration Insurance [Roll Forward]
Balance, beginning of period	20,691,139	20,167,713
Deposits	582,832	529,212
Interest credited(4)	145,451	138,059
Policy charges	(459,618)	(455,538)
Surrenders and withdrawals	(230,465)	(199,907)
Benefit payments	(31,911)	(17,856)
Transfer to (from) Policyholder Account Balance (to) from Separate Account	90,828	84,803
Change in market value and other adjustments	9,260	37,169
Balance, end of period	20,797,516	20,283,655
Total Policyholders' account balance	$ 17,526,199	$ 17,462,288
Weighted-average crediting rate	2.80%	2.73%
Net amount at risk	$ 350,940,996	$ 327,231,561
Cash surrender value	$ 19,498,691	$ 18,899,950