Liability for Future Policy Benefits (Benefit Reserves) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Other adjustments	$ 20,643	$ (3,952)	$ (55,099)
Other Businesses
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period	1,765	2,127
Balance after transition, at current discount rate	1,474	1,765	2,127
Total
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period	18,656,760	18,042,105
Balance after transition, at current discount rate	17,928,959	18,656,760	18,042,105
Term Life
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of period	10,927,833	10,911,794	12,485,056
Effect of cumulative changes in discount rate assumptions, beginning of period	225,711	554,896	(1,826,120)
Balance at original discount rate, beginning of period	11,153,544	11,466,690	10,658,936
Effect of assumption update		21,466	(790)	$ 1,295,294
Effect of actual variances from expected experiences and other activity		(219,878)	(200,513)	(112,661)
Adjusted balance, beginning of period		10,955,132	11,265,387	11,841,569
Issuances	827,606	712,495	439,874
Net Premium / Consideration Collected	(1,319,501)	(1,345,514)	(1,339,902)
Interest accural	511,817	521,176	525,149
Other adjustments	7,092
Balance at original discount rate, end of period	10,982,146	11,153,544	11,466,690
Effect of cumulative changes in discount rate assumptions, end of period	(567,443)	(225,711)	(554,896)
Balance, end of period	10,414,703	10,927,833	10,911,794
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period	18,426,207	17,835,251	20,937,097
Effect of cumulative changes in discount rate assumptions, beginning of period	331,571	962,035	(3,607,275)
Balance at original discount rate, beginning of period	18,757,778	18,797,286	17,329,822
Effect of assumption update		21,480	(1,044)	1,756,995
Effect of actual variance from expected experience and other activity		(259,137)	(263,243)	(206,175)
Adjusted balance, beginning of period		18,520,121	18,532,999	18,880,642
Issuances	827,606	712,495	439,874
Interest accrual	893,983	895,023	888,525
Benefit Payments	(1,471,863)	(1,386,583)	(1,416,823)
Other adjustments	11,225	3,844	5,068
Balance at original discount rate, end of period	18,781,072	18,757,778	18,797,286
Effect of cumulative changes in discount rate assumptions, end of period	(1,091,673)	(331,571)	(962,035)
Balance after transition, at current discount rate	17,689,399	18,426,207	17,835,251
Balance, end of period, pre-flooring	7,274,696	7,498,374	6,923,457
Flooring impact, end of period	44	44	0
Balance, end of period, post-flooring	7,274,740	7,498,418	6,923,457
Less: Reinsurance Recoverable	6,753,842	6,817,488	6,497,257
Balance after transition, net of reinsurance recoverable	520,898	680,930	426,200
Term Life | Gross Basis
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Undiscounted expected future gross premiums	21,815,010	21,871,767	22,223,836
Discounted expected future gross premiums (at original discount rate)	14,889,078	15,027,611	15,322,180
Discounted expected future gross premiums (at current discount rate)	14,154,658	14,748,999	14,587,657
Undiscounted expected future benefits and expenses	$ 29,163,241	$ 29,118,532	$ 29,330,574
Weighted-average duration of the liability in years (at original discount rate)	10 years	10 years	11 years
Weighted-average duration of the liability in years (at current discount rate)	9 years	10 years	10 years
Weighted-Average Interest Rate (At Original Discount Rate)	5.13%	5.17%	5.23%
Weighted-average interest rate (at current discount rate)	5.59%	4.99%	5.39%
Fixed Annuities
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of period	$ 0	$ 0	$ 0
Effect of cumulative changes in discount rate assumptions, beginning of period	0	0	0
Balance at original discount rate, beginning of period	0	0	0
Effect of assumption update		0	0	0
Effect of actual variances from expected experiences and other activity		58	(989)	(1,143)
Adjusted balance, beginning of period		58
Issuances	35,717	36,646	30,469
Net Premium / Consideration Collected	(35,775)	(35,657)	(29,326)
Interest accural	0	0	0
Other adjustments	0
Balance at original discount rate, end of period	0	0	0
Effect of cumulative changes in discount rate assumptions, end of period	0	0	0
Balance, end of period	0	0	0
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period	228,788	204,727	237,065
Effect of cumulative changes in discount rate assumptions, beginning of period	19,521	24,876	(16,704)
Balance at original discount rate, beginning of period	248,309	229,603	220,361
Effect of assumption update		(3,643)	0	0
Effect of actual variance from expected experience and other activity		502	6,991	(1,639)
Adjusted balance, beginning of period		245,168	236,594	218,722
Issuances	35,717	36,646	30,469
Interest accrual	9,119	8,440	7,836
Benefit Payments	(32,225)	(33,287)	(27,138)
Other adjustments	(251)	(84)	(286)
Balance at original discount rate, end of period	257,528	248,309	229,603
Effect of cumulative changes in discount rate assumptions, end of period	(19,442)	(19,521)	(24,876)
Balance after transition, at current discount rate	238,086	228,788	204,727
Balance, end of period, pre-flooring	238,086	228,788	204,727
Flooring impact, end of period	0	0	0
Balance, end of period, post-flooring	238,086	228,788	204,727
Less: Reinsurance Recoverable	20,516	18,489	16,460
Balance after transition, net of reinsurance recoverable	217,570	210,299	188,267
Fixed Annuities | Gross Basis
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Undiscounted expected future gross premiums	0	0	0
Discounted expected future gross premiums (at original discount rate)	0	0	0
Discounted expected future gross premiums (at current discount rate)	0	0	0
Undiscounted expected future benefits and expenses	$ 346,892	$ 332,902	$ 306,286
Weighted-average duration of the liability in years (at original discount rate)	7 years	7 years	7 years
Weighted-average duration of the liability in years (at current discount rate)	6 years	6 years	6 years
Weighted-Average Interest Rate (At Original Discount Rate)	3.94%	3.70%	3.60%
Weighted-average interest rate (at current discount rate)	5.49%	4.95%	5.33%
Fixed Annuity
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Adjusted balance, beginning of period			$ (989)	(1,143)
Term Life and Fixed Annuities
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of period	$ 10,927,833	$ 10,911,794	12,485,056
Effect of cumulative changes in discount rate assumptions, beginning of period	225,711	554,896	(1,826,120)
Balance at original discount rate, beginning of period	11,153,544	11,466,690	10,658,936
Effect of assumption update		21,466	(790)	1,295,294
Effect of actual variances from expected experiences and other activity		(219,820)	(201,502)	(113,804)
Adjusted balance, beginning of period		10,955,190	11,264,398	11,840,426
Issuances	863,323	749,141	470,343
Net Premium / Consideration Collected	(1,355,276)	(1,381,171)	(1,369,228)
Interest accural	511,817	521,176	525,149
Other adjustments	7,092
Balance at original discount rate, end of period	10,982,146	11,153,544	11,466,690
Effect of cumulative changes in discount rate assumptions, end of period	(567,443)	(225,711)	(554,896)
Balance, end of period	10,414,703	10,927,833	10,911,794
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period	18,654,995	18,039,978	21,174,162
Effect of cumulative changes in discount rate assumptions, beginning of period	351,092	986,911	(3,623,979)
Balance at original discount rate, beginning of period	19,006,087	19,026,889	17,550,183
Effect of assumption update		17,837	(1,044)	1,756,995
Effect of actual variance from expected experience and other activity		(258,635)	(256,252)	(207,814)
Adjusted balance, beginning of period		18,765,289	18,769,593	$ 19,099,364
Issuances	863,323	749,141	470,343
Interest accrual	903,102	903,463	896,361
Benefit Payments	(1,504,088)	(1,419,870)	(1,443,961)
Other adjustments	10,974	3,760	4,782
Balance at original discount rate, end of period	19,038,600	19,006,087	19,026,889
Effect of cumulative changes in discount rate assumptions, end of period	(1,111,115)	(351,092)	(986,911)
Balance after transition, at current discount rate	17,927,485	18,654,995	18,039,978
Balance, end of period, pre-flooring	7,512,782	7,727,162	7,128,184
Flooring impact, end of period	44	44	0
Balance, end of period, post-flooring	7,512,826	7,727,206	7,128,184
Less: Reinsurance Recoverable	6,774,358	6,835,977	6,513,717
Balance after transition, net of reinsurance recoverable	738,468	891,229	614,467
Nonparticipating Traditional and Limited-Pay Business
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Loss in net income	28,000	30,000	83,000
Gain in net income	$ 29,000	$ 31,000	$ 82,000