Equity (Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance			$ 546,128
Income tax benefit (expense)	$ (45,396)	$ (68,391)	28,335	$ (40,104)
Ending Balance	435,447		435,447
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance			(7,797)	(7,917)
Change in OCI before reclassifications			(4,781)	(3,888)
Amounts reclassified from AOCI			0	0
Income tax benefit (expense)			149	12
Ending Balance	(12,429)	(11,793)	(12,429)	(11,793)
Net unrealized investment gains (losses)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance			553,925	289,359
Change in OCI before reclassifications			(129,762)	195,529
Amounts reclassified from AOCI			(4,473)	(4,502)
Income tax benefit (expense)			28,186	(40,116)
Ending Balance	447,876	440,270	447,876	440,270
Accumulated Other Comprehensive   Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance			546,128	281,442
Change in OCI before reclassifications			(134,543)	191,641
Amounts reclassified from AOCI			(4,473)	(4,502)
Income tax benefit (expense)			28,335	(40,104)
Ending Balance	435,447	428,477	435,447	428,477
Cash flow hedges | Net unrealized investment gains (losses)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance			(8,000)	26,000
Ending Balance	$ 12,000	$ 94,000	$ 12,000	$ 94,000