Consolidation and Basis of Presentation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Decrease to deferred federal income tax liability	$ (30,438)		$ (36,767)
Decrease to retained earnings	(2,009,476)		(2,014,570)
Other net investment gains (losses)	3,485	$ 4,629
Net OTTI losses recognized in earnings	0	0
Earnings (loss) before Federal income taxes	(2,979)	50,591
Federal income taxes	(917)	10,393
Net earnings (loss)	(2,062)	40,198
Unrealized Gains and Losses on Available-for-sale Securities | Amount Reclassified From Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other net investment gains (losses)	761	1,099
Net OTTI losses recognized in earnings	0	0
Earnings (loss) before Federal income taxes	761	1,099
Federal income taxes	160	231
Net earnings (loss)	$ 601	$ 868
Restatement adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Increase in future policy benefits liability			15,000
Decrease to deferred federal income tax liability			3,200
Decrease to retained earnings			$ 11,800