Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net income	$ 576,601	$ 467,030	$ 475,985
Adjustments to reconcile net income to cash provided by (used in) operating activities:
Change in future policy benefits and other policy liabilities	102,540	(35,831)	(417,640)
Deferral of policy acquisition costs	(514,970)	(503,336)	(552,192)
Amortization of deferred policy acquisition costs	275,816	261,629	238,270
Deferred tax provision	(43,380)	(52,802)	2,760
Change in income taxes	(8,842)	26,398	1,650
Investment (gains) losses	5,896	995	(5,872)
Accretion and amortization of investments	(2,034)	3,329	5,118
Depreciation and amortization	31,964	34,174	29,836
Change in reinsurance recoverables	237,328	461,925	769,012
Change in agent balances, due premiums and other receivables	(18,761)	(475)	6,046
Change in renewal commissions receivable	9,785	19,845	(23,459)
Trading securities sold, matured, or called (acquired), net	(14,552)	19,962	(8,817)
Share-based compensation	18,911	22,361	16,842
Goodwill impairment loss		60,000	76,000
Loss on extinguishment of debt			8,927
Change in other operating assets and liabilities, net	36,215	(27,539)	34,490
Net cash provided by (used in) operating activities	692,517	757,665	656,956
Available-for-sale investments sold, matured or called:
Fixed-maturity securities — sold	19,230	23,628	131,953
Fixed-maturity securities — matured or called	263,443	359,717	454,135
Short-term investments — sold	28,799	28,251	50,065
Short-term investments — matured or called	61,782	85,302	40,000
Equity securities - sold	3,051	16	718
Equity securities - matured or called		3,063
Available-for-sale investments acquired:
Fixed-maturity securities	(412,262)	(580,485)	(901,591)
Short-term investments	(19,767)	(97,415)	(176,125)
Equity securities — acquired	(430)	(187)	(3,391)
Purchases of property and equipment and other investing activities, net	(33,897)	(25,805)	(24,688)
Cash collateral received (returned) on loaned securities, net	(1,153)	6,409	22,375
Sales (purchases) of short-term investments using securities lending collateral, net	1,153	(6,409)	(22,375)
Purchase of business, net of cash acquired		3,867	(494,459)
Net cash provided by (used in) investing activities	(90,051)	(200,048)	(923,383)
Cash flows from financing activities:
Dividends paid	(93,715)	(83,783)	(74,636)
Common stock repurchased	(375,062)	(356,306)	(18,751)
Proceeds from revolving credit facility			125,000
Repayment of revolving credit facility			(125,000)
Proceeds from issuance of debt			597,300
Debt issuance costs			(5,332)
Repayment of debt			(383,691)
Payment on note issued to seller of business		(12,364)
Tax withholdings on share-based compensation	(10,579)	(5,135)	(6,652)
Finance leases	(265)	(262)	(264)
Net cash provided by (used in) financing activities	(479,621)	(457,850)	107,974
Effect of foreign exchange rate changes on cash	1,063	(3,028)	3,385
Change in cash and cash equivalents	123,908	96,739	(155,068)
Cash and cash equivalents, beginning of period	489,240	392,501	547,569
Cash and cash equivalents, end of period	613,148	489,240	392,501
Supplemental disclosures of cash flow information:
Income taxes paid	227,271	178,218	154,812
Interest paid	$ 27,279	$ 27,060	33,905
Non-cash activities:
Increases in note issued to seller of business			$ 15,000