Consolidated Statements of Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning of period			$ 7,469,237
Other comprehensive income (loss)	$ 430,496	$ (141,146)	322,693	$ (58,237)
End of period	8,439,402		8,439,402
Net realized and unrealized (losses) gains on investments	(23,362)	(40,855)	(72,165)	50,403
Income before income taxes	474,449	419,949	1,536,192	1,253,205
Tax effect	(109,135)	(86,519)	(356,958)	(268,322)
Net income before noncontrolling interests	365,314	333,430	1,179,234	984,883
Total change in unrealized investment gains (losses)	480,768	(150,455)	370,831	(62,476)
Net change in period	49,503	(22,781)	25,160	(7,387)
Other comprehensive income (loss), pre-tax	530,271	(173,236)	395,991	(69,863)
Other comprehensive income (loss), tax effect	(99,775)	32,090	(73,298)	11,626
Other comprehensive income (loss), net of tax	430,496	(141,146)	322,693	(58,237)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning of period	(1,033,640)	(1,181,673)	(925,838)	(1,264,581)
Other comprehensive income before reclassifications	423,613	(155,799)	243,247	(110,474)
Amounts reclassified from AOCI	6,883	14,653	79,446	52,237
Other comprehensive income (loss)	430,496	(141,146)	322,693	(58,237)
Unrealized investment gain related to noncontrolling interest	0	0	1	(1)
End of period	(603,144)	(1,322,819)	(603,144)	(1,322,819)
Other comprehensive income (loss), net of tax	430,496	(141,146)	322,693	(58,237)
Accumulated Other Comprehensive Income (Loss) | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Income before income taxes	8,713	18,548	100,565	66,123
Tax effect	(1,830)	(3,895)	(21,119)	(13,886)
Net income before noncontrolling interests	6,883	14,653	79,446	52,237
Unrealized Investment (Losses) Gains
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning of period	(669,813)	(825,391)	(586,354)	(892,905)
Other comprehensive income before reclassifications	374,110	(133,018)	218,087	(103,087)
Amounts reclassified from AOCI	6,883	14,653	79,446	52,237
Other comprehensive income (loss)	380,993	(118,365)	297,533	(50,850)
Unrealized investment gain related to noncontrolling interest	0	0	1	(1)
End of period	(288,820)	(943,756)	(288,820)	(943,756)
Total change in unrealized investment gains (losses)	480,768	(150,455)	370,831	(62,476)
Unrealized investment gains, tax effect	(99,775)	32,090	(73,298)	11,626
Unrealized investment gains (losses), after-tax amounts	380,993	(118,365)	297,533	(50,850)
Other comprehensive income (loss), net of tax	380,993	(118,365)	297,533	(50,850)
Unrealized Investment (Losses) Gains | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Net realized and unrealized (losses) gains on investments	8,713	18,548	100,565	66,123
Tax effect	(1,830)	(3,895)	(21,119)	(13,886)
Net income before noncontrolling interests	6,883	14,653	79,446	52,237
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning of period	(363,827)	(356,282)	(339,484)	(371,676)
Other comprehensive income before reclassifications	49,503	(22,781)	25,160	(7,387)
Amounts reclassified from AOCI	0	0		0
Other comprehensive income (loss)	49,503	(22,781)	25,160	(7,387)
Unrealized investment gain related to noncontrolling interest		0	0	0
End of period	(314,324)	(379,063)	(314,324)	(379,063)
Currency translation adjustment, pre-tax	49,503	(22,781)	25,160	(7,387)
Currency translation adjustment, tax effect	0	0	0	0
Net change in period	49,503	(22,781)	25,160	(7,387)
Other comprehensive income (loss), net of tax	49,503	(22,781)	25,160	(7,387)
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