Policyholders' Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Additional Liability, Long-Duration Insurance [Roll Forward]
Balance, beginning of period	$ 53,012,800
Transfer to (from) Policyholder Account Balance (to) from Separate Account	78,080	$ 35,164
Unearned revenue reserve	3,908,497	3,234,755
Other	103,851	100,146
Total Policyholders' account balance	$ 57,764,158	$ 43,799,121
Weighted-average crediting rate	2.17%	2.35%
Net amount at risk	$ 327,231,579	$ 308,975,510
Cash surrender value	48,856,565	36,039,509
Total
Additional Liability, Long-Duration Insurance [Roll Forward]
Balance, beginning of period	49,168,791	38,744,221
Deposits	3,708,020	2,043,604
Interest credited	279,719	232,378
Policy charges	(457,032)	(457,837)
Surrenders and withdrawals	(483,591)	(372,916)
Benefit payments	(35,661)	(45,610)
Transfer to (from) Policyholder Account Balance (to) from Separate Account	78,080	35,164
Change in market value and other adjustments	1,493,484	285,216
Balance, end of period	53,751,810	40,464,220
Fixed Annuities
Additional Liability, Long-Duration Insurance [Roll Forward]
Balance, beginning of period	6,164,313	3,575,824
Deposits	1,553,852	564,236
Interest credited	43,517	11,996
Policy charges		(118)
Surrenders and withdrawals	(103,696)	(43,158)
Benefit payments	(12,879)	(10,215)
Transfer to (from) Policyholder Account Balance (to) from Separate Account	0	0
Change in market value and other adjustments	88,291	9,343
Balance, end of period	7,735,606	4,107,908
Total Policyholders' account balance	$ 3,148,584	$ 1,445,843
Weighted-average crediting rate	2.50%	1.25%
Net amount at risk	$ 18	$ 7
Cash surrender value	6,674,346	3,459,140
Variable Annuity
Additional Liability, Long-Duration Insurance [Roll Forward]
Balance, beginning of period	22,836,765	16,432,032
Deposits	1,624,956	948,987
Interest credited	98,143	78,629
Policy charges	(3,702)	(5,729)
Surrenders and withdrawals	(179,988)	(113,424)
Benefit payments	(4,926)	(10,624)
Transfer to (from) Policyholder Account Balance (to) from Separate Account	(6,723)	10,253
Change in market value and other adjustments	1,368,024	191,448
Balance, end of period	25,732,549	17,531,572
Total Policyholders' account balance	$ 2,821,316	$ 3,172,877
Weighted-average crediting rate	1.62%	1.85%
Net amount at risk	$ 0	$ 0
Cash surrender value	23,282,269	15,338,366
Variable/Universal Life
Additional Liability, Long-Duration Insurance [Roll Forward]
Balance, beginning of period	20,167,713	18,736,365
Deposits	529,212	530,381
Interest credited	138,059	141,753
Policy charges	(455,538)	(451,990)
Surrenders and withdrawals	(199,907)	(216,334)
Benefit payments	(17,856)	(24,771)
Transfer to (from) Policyholder Account Balance (to) from Separate Account	84,803	24,911
Change in market value and other adjustments	37,169	84,425
Balance, end of period	20,283,655	18,824,740
Total Policyholders' account balance	$ 17,462,288	$ 16,575,928
Weighted-average crediting rate	2.73%	3.02%
Net amount at risk	$ 327,231,561	$ 308,975,503
Cash surrender value	18,899,950	$ 17,242,003
Fixed Annuity Netting
Additional Liability, Long-Duration Insurance [Roll Forward]
Policy charges	$ 2,208