Consolidated Statements of Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning of period			$ 6,768,161
Other comprehensive loss	$ (141,146)	$ (356,180)	(58,237)	$ (1,103,854)
End of period	6,929,909		6,929,909
Net realized and unrealized (losses) gains on investments	(40,855)	(66,282)	50,403	139,664
Income before income taxes	419,949	286,265	1,253,205	1,241,260
Tax effect	(86,519)	(55,791)	(268,322)	(238,290)
Net income before noncontrolling interests	333,430	230,474	984,883	1,002,970
Total change in unrealized investment losses	(150,455)	(394,832)	(62,476)	(1,365,064)
Net change in period	(22,781)	(40,516)	(7,387)	(27,637)
Other comprehensive income (loss), pre-tax	(173,236)	(435,348)	(69,863)	(1,392,701)
Other comprehensive income (loss), tax effect	32,090	79,168	11,626	288,847
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning of period	(1,181,673)	(1,029,630)	(1,264,581)	(281,955)
Other comprehensive income (loss) before reclassifications	(155,799)	(375,550)	(110,474)	(1,162,294)
Amounts reclassified from AOCI	14,653	19,370	52,237	58,440
Other comprehensive loss	(141,146)	(356,180)	(58,237)	(1,103,854)
Unrealized investment loss related to noncontrolling interest	0	0	(1)	(1)
End of period	(1,322,819)	(1,385,810)	(1,322,819)	(1,385,810)
Accumulated Other Comprehensive Income (Loss) | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Income before income taxes	18,548	24,519	66,123	73,975
Tax effect	(3,895)	(5,149)	(13,886)	(15,535)
Net income before noncontrolling interests	14,653	19,370	52,237	58,440
Unrealized Investment Gains (Losses)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning of period	(825,391)	(669,654)	(892,905)	90,900
Other comprehensive income (loss) before reclassifications	(133,018)	(335,034)	(103,087)	(1,134,657)
Amounts reclassified from AOCI	14,653	19,370	52,237	58,440
Other comprehensive loss	(118,365)	(315,664)	(50,850)	(1,076,217)
Unrealized investment loss related to noncontrolling interest	0	0	(1)	(1)
End of period	(943,756)	(985,318)	(943,756)	(985,318)
Total change in unrealized investment losses	(150,455)	(394,832)	(62,476)	(1,365,064)
Unrealized investment gains, tax effect	32,090	79,168	11,626	288,847
Unrealized investment gains (losses), after-tax amounts	(118,365)	(315,664)	(50,850)	(1,076,217)
Unrealized Investment Gains (Losses) | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Net realized and unrealized (losses) gains on investments	18,548	24,519	66,123	73,975
Tax effect	(3,895)	(5,149)	(13,886)	(15,535)
Net income before noncontrolling interests	14,653	19,370	52,237	58,440
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning of period	(356,282)	(359,976)	(371,676)	(372,855)
Other comprehensive income (loss) before reclassifications	(22,781)	(40,516)	(7,387)	(27,637)
Amounts reclassified from AOCI	0	0	0	0
Other comprehensive loss	(22,781)	(40,516)	(7,387)	(27,637)
Unrealized investment loss related to noncontrolling interest	0		0	0
End of period	(379,063)	(400,492)	(379,063)	(400,492)
Currency translation adjustment, pre-tax	(22,781)	(40,516)	(7,387)	(27,637)
Currency translation adjustment, tax effect	0	0	0	0
Net change in period	(22,781)	(40,516)	(7,387)	(27,637)
Currency Translation Adjustments | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Income before income taxes	0	0	0	0
Tax effect	0	0	0	0
Net income before noncontrolling interests	$ 0	$ 0	$ 0	$ 0