Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Statement of Cash Flows [Abstract]
Cash provided from (used for) operating activities	$ 1,065,513	$ 1,091,028
Investments sold or matured:
Fixed maturities available for sale—sold	674,125	192,007
Fixed maturities available for sale—matured or other redemptions	161,275	212,936
Mortgage loans	29,433	32,164
Other long-term investments	29,995	100,999
Total investments sold or matured	894,828	538,106
Acquisition of investments:
Fixed maturities—available for sale	(1,000,665)	(1,076,699)
Mortgage loans	(134,667)	(95,995)
Other long-term investments	(445,776)	(103,098)
Total investments acquired	(1,581,108)	(1,275,792)
Net (increase) decrease in policy loans	(34,052)	(29,687)
Net (increase) decrease in short-term investments	(18,761)	30,187
Additions to property and equipment	(56,047)	(36,449)
Other investing activities	(96)	0
Investments in low-income housing interests	(27,840)	(54,337)
Cash provided from (used for) investing activities	(822,884)	(827,972)
Cash provided from (used for) financing activities:
Issuance of common stock	34,851	61,079
Cash dividends paid to shareholders	(65,292)	(62,945)
Repayment of debt	0	(165,612)
Proceeds from issuance of debt	530,000	170,000
Payment for debt issuance costs	(7,138)	(757)
Net borrowing from FHLB	17,000	198,000
Net borrowing (repayment) of commercial paper	31,443	(34,066)
Proceeds from commercial paper with original maturities greater than 90 days	387,247	0
Repayment of commercial paper with original maturities greater than 90 days	(314,836)	0
Acquisition of treasury stock	(950,448)	(365,929)
Net receipts (payments) from deposit-type products	122,291	(69,526)
Cash provided from (used for) financing activities	(214,882)	(269,756)
Effect of foreign exchange rate changes on cash	3,646	(313)
Net increase (decrease) in cash	31,393	(7,013)
Cash at beginning of year	103,156	92,559
Cash at end of period	$ 134,549	$ 85,546