Minimum Guarantees - Amounts Paid and Incurred for GMDB (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Balances, January 1,	$ 10,280	$ 5,566	$ 5,993
Incurred guaranteed benefits	(2,608)	5,634	305
Paid guaranteed benefits	(503)	(920)	(732)
Balances, December 31,	7,169	10,280	5,566
GMDB
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Balances, January 1,	5,467	5,566	5,993
Incurred guaranteed benefits	132	821	305
Paid guaranteed benefits	(503)	(920)	(732)
Balances, December 31,	5,096	5,467	5,566
GLWB
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Balances, January 1,	4,813	0	0
Incurred guaranteed benefits	(2,740)	4,813	0
Paid guaranteed benefits	0	0	0
Balances, December 31,	$ 2,073	$ 4,813	$ 0