Investments (Net Unrealized Gains Losses on Investments by Asset Class) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Gain (Loss) on Securities [Line Items]
Net Unrealized Gains (Losses) on Investments	$ 586,389	$ 849,349	$ 425,180
Fixed Maturities | Available-for-sale Securities | OTTI
Gain (Loss) on Securities [Line Items]
Net Unrealized Gains (Losses) on Investments			1,568
Fixed Maturities | Available-for-sale Securities | All other
Gain (Loss) on Securities [Line Items]
Net Unrealized Gains (Losses) on Investments			397,136
Fixed Maturities | Available-for-sale Securities | With an allowance
Gain (Loss) on Securities [Line Items]
Net Unrealized Gains (Losses) on Investments	3,685	0
Fixed Maturities | Available-for-sale Securities | Without an allowance
Gain (Loss) on Securities [Line Items]
Net Unrealized Gains (Losses) on Investments	540,881	857,599
Derivatives designated as cash flow hedges
Gain (Loss) on Securities [Line Items]
Net Unrealized Gains (Losses) on Investments	39,896	(8,112)	26,126
Affiliated notes
Gain (Loss) on Securities [Line Items]
Net Unrealized Gains (Losses) on Investments	73	4,024	4,715
Other invested assets
Gain (Loss) on Securities [Line Items]
Net Unrealized Gains (Losses) on Investments	$ 1,854	$ (4,162)	$ (4,365)