Certain Long-Duration Contracts With Guarantees (Changes in Deferred Sales Inducements, Reported as "Interest credited to policyholders' account (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Movement in Deferred Sales Inducements [Roll Forward]
Deferred Sales Inducements, Beginning Balance	$ 665,207	$ 809,247	$ 556,830
Capitalization	873	11,515	31,370
Amortization - Impact of assumption and experience unlocking and true-ups	21,125	45,417	13,038
Amortization - All other	(206,263)	(204,563)	179,219
Change in unrealized investment gains and losses	11,063	3,591	28,790
Ceded DSI upon Reinsurance Treaty with Prudential Insurance	(39,253)
Deferred Sales Inducements, Ending Balance	$ 452,752	$ 665,207	$ 809,247