Equity (Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 281,442
Income tax benefit (expense)	28,287	$ (33,633)
Ending Balance	155,061
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(7,917)	(17,448)
Change in OCI before reclassifications	(20,402)	6,049
Amounts reclassified from AOCI	0	0
Income tax benefit (expense)	92	(19)
Ending Balance	(28,227)	(11,418)
Net unrealized investment gains (losses)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	289,359	(10,848)
Change in OCI before reclassifications	(125,148)	156,295
Amounts reclassified from AOCI	(9,118)	3,790
Income tax benefit (expense)	28,195	(33,614)
Ending Balance	183,288	115,623
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	281,442	(28,296)
Change in OCI before reclassifications	(145,550)	162,344
Amounts reclassified from AOCI	(9,118)	3,790
Income tax benefit (expense)	28,287	(33,633)
Ending Balance	155,061	104,205
Cash flow hedges \| Net unrealized investment gains (losses)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	26,000	22,000
Ending Balance	$ 124,000	$ 15,000

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount before tax and reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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