Equity (Reclassification out of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Net Unrealized Investment Gains (Losses)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from AOCI	$ 15,612	$ (1,093,820)
Total reclassifications for the period
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from AOCI	15,612	(1,093,820)
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	(15,612)	1,093,820
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	(15,612)	1,093,820
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)	(20,589)	1,081,504
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)	$ 4,977	$ 12,316