Consolidated Statement of Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period	$ 6,325,797
Other comprehensive (loss) gain	(219,781)	$ 170,177	$ 253,068
End of period	6,667,730	6,325,797
Unrealized investment gains (losses), before tax	106,958	73,514	120,703
Pre-Tax Income (Loss)	1,282,905	704,802	852,920
Federal and foreign income taxes	(251,890)	(171,817)	(168,935)
Net income	1,031,015	532,985	683,985
Unrealized investment gains, before tax	(254,939)	164,645	261,970
Currency translation adjustments, before tax	(20,969)	29,927
Other comprehensive income (loss), before tax	(275,908)	194,572
Unrealized investment gains, tax	56,127	(24,395)
Currency translation adjustments, tax	0	0
Other comprehensive income (loss), tax	56,127	(24,395)
Unrealized investment gains, net of tax	(198,812)	140,250
Change in unrealized translation adjustments	(20,969)	29,927	37,166
Unrealized Investment Gains (Losses)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period	289,714	124,514
Other comprehensive loss before reclassifications	(222,359)	114,049
Amounts reclassified from AOCI	23,547	26,201
Other comprehensive (loss) gain	(198,812)	140,250
Unrealized investment loss related to noncontrolling interest	(2)	(2)
End of period	90,900	289,714	124,514
Unrealized Investment Gains (Losses) | Cumulative Effect, Period Of Adoption, Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period		24,952
End of period			24,952
Unrealized Investment Gains (Losses) | Cumulative Effect, Period Of Adoption, Adjusted Balance
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period		149,466
End of period			149,466
Unrealized Investment Gains (Losses) | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized investment gains (losses), before tax	29,806	33,166
Federal and foreign income taxes	(6,259)	(6,965)
Net income	23,547	26,201
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period	(351,886)	(381,813)	(418,979)
Other comprehensive loss before reclassifications	(20,969)	29,927
Amounts reclassified from AOCI	0	0
Other comprehensive (loss) gain	(20,969)	29,927
Unrealized investment loss related to noncontrolling interest	0	0
End of period	(372,855)	(351,886)	(381,813)
Change in unrealized translation adjustments	(20,969)	29,927	37,166
Currency Translation Adjustments | Cumulative Effect, Period Of Adoption, Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period		0
End of period			0
Currency Translation Adjustments | Cumulative Effect, Period Of Adoption, Adjusted Balance
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period		(381,813)
End of period			(381,813)
Currency Translation Adjustments | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-Tax Income (Loss)	0	0
Federal and foreign income taxes	0	0
Net income	0	0
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period	(62,172)	(257,299)
Other comprehensive loss before reclassifications	(243,328)	143,976
Amounts reclassified from AOCI	23,547	26,201
Other comprehensive (loss) gain	(219,781)	170,177
Unrealized investment loss related to noncontrolling interest	(2)	(2)
End of period	(281,955)	(62,172)	(257,299)
Accumulated Other Comprehensive Loss | Cumulative Effect, Period Of Adoption, Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period		24,952
End of period			24,952
Accumulated Other Comprehensive Loss | Cumulative Effect, Period Of Adoption, Adjusted Balance
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period		(232,347)
End of period			$ (232,347)
Accumulated Other Comprehensive Loss | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-Tax Income (Loss)	29,806	33,166
Federal and foreign income taxes	(6,259)	(6,965)
Net income	$ 23,547	$ 26,201