Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Cash Flows [Abstract]
Cash provided from (used for) operating activities	$ 350,806	$ 477,330
Investments sold or matured:
Fixed maturities available for sale—sold	27,853	15,705
Fixed maturities available for sale—matured or other redemptions	59,871	61,560
Mortgage loans	7,896	21
Other long-term investments	573	1,929
Total investments sold or matured	96,193	79,215
Acquisition of investments:
Fixed maturities—available for sale	(682,427)	(285,505)
Mortgage loans	(58,406)	(24,186)
Other long-term investments	(80,468)	(23,712)
Total investments acquired	(821,301)	(333,403)
Net (increase) decrease in policy loans	(7,621)	(7,870)
Net (increase) decrease in short-term investments	23,327	39,744
Additions to property and equipment	(9,106)	(8,210)
Investments in low-income housing interests	(13,428)	(17,246)
Cash provided from (used for) investing activities	(731,936)	(247,770)
Cash provided from (used for) financing activities:
Issuance of common stock	29,763	37,024
Cash dividends paid to shareholders	(21,117)	(20,071)
Net borrowing from FHLB	242,000	45,000
Net borrowing (repayment) of commercial paper	5,304	20,070
Acquisition of treasury stock	(23,469)	(179,276)
Net receipts (payments) from deposit-type products	124,475	(54,487)
Cash provided from (used for) financing activities	356,956	(151,740)
Effect of foreign exchange rate changes on cash	4,565	1,729
Net increase (decrease) in cash	(19,609)	79,549
Cash at beginning of year	103,156	92,559
Cash at end of period	$ 83,547	$ 172,108