Equity (Reclassification out of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Net Unrealized Investment Gains (Losses)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from AOCI	$ (29,479)	$ 1,584
Total reclassifications for the period
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from AOCI	(29,479)	1,584
Reclassification out of Accumulated Other Comprehensive Income \| Net Unrealized Investment Gains (Losses)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from AOCI	29,479	(1,584)
Reclassification out of Accumulated Other Comprehensive Income \| Total reclassifications for the period
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from AOCI	29,479	(1,584)
Reclassification out of Accumulated Other Comprehensive Income \| Net unrealized investment gains (losses) on available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net unrealized investment gains (losses)	6,422	(731)
Reclassification out of Accumulated Other Comprehensive Income \| Currency/Interest Rate \| Cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net unrealized investment gains (losses)	$ 23,057	$ (853)

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Publisher FASB
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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period.

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