Fair Value - Recurring basis Level 3 rollforward (Details) - Recurring basis - Significant unobservable inputs (Level 3) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014
Recurring Level 3 financial assets and liabilities
Balance at the beginning of the period		$ 4,538		$ 5,878		$ 259,642
Net Income				0		(17)
Other comprehensive income (loss)				(178)		(193)
Settlements				(1,126)		(651)	[1]
Transfers out of Level 3 (1)				(36)	[2]	(252,903)
Balance at the end of the period				4,538		5,878
Total gains (losses) for the period included in net income attributable to the change in unrealized gains and losses relating to assets held at December 31, 2015				0		0
Corporate debt securities
Recurring Level 3 financial assets and liabilities
Balance at the beginning of the period		4,538		5,842		6,652
Net Income		0		0		0
Other comprehensive income (loss)		273		(178)		(178)
Settlements		(1,478)		(1,126)		(632)	[1]
Transfers into Level 3 (1)	[1]	11,236
Transfers out of Level 3 (1)		(2,930)	[3]	0	[2]	0
Balance at the end of the period		11,639		4,538		5,842
Total gains (losses) for the period included in net income attributable to the change in unrealized gains and losses relating to assets held at December 31, 2015		0		0		0
Asset-backed securities
Recurring Level 3 financial assets and liabilities
Balance at the beginning of the period		0		36		252,958
Net Income				0		0
Other comprehensive income (loss)				0		0
Settlements				0		(19)	[1]
Transfers out of Level 3 (1)				(36)	[2]	(252,903)
Balance at the end of the period				0		36
Total gains (losses) for the period included in net income attributable to the change in unrealized gains and losses relating to assets held at December 31, 2015				0		0
Fixed maturities available-for-sale, Collateralized debt obligations
Recurring Level 3 financial assets and liabilities
Balance at the beginning of the period				0		32
Net Income						(17)
Other comprehensive income (loss)						(15)
Settlements	[1]					0
Transfers out of Level 3 (1)						0
Balance at the end of the period						0
Total gains (losses) for the period included in net income attributable to the change in unrealized gains and losses relating to assets held at December 31, 2015						0
Embedded derivatives - GLWB
Recurring Level 3 financial assets and liabilities
Balance at the beginning of the period		11,257		0
Net Income		(5,545)		11,257
Other comprehensive income (loss)		0		0
Settlements		0		0
Transfers out of Level 3 (1)		0	[3]	0
Balance at the end of the period		5,712		11,257		$ 0
Total gains (losses) for the period included in net income attributable to the change in unrealized gains and losses relating to assets held at December 31, 2015		$ (5,545)		$ 11,257

[1] 1) Transfers out of Level 3 are due primarily to increased observability of inputs in valuation methodologies as evidenced by corroboration of market prices with multiple pricing vendors and internal models.

[2] 1) Transfers out of Level 3 are due primarily to increased observability of inputs in valuation methodologies as evidenced by corroboration of market prices with multiple pricing vendors and internal models.

[3] Transfers out of Level 3 are due primarily to increased observability of inputs in valuation methodologies as evidenced by corroboration of market prices with multiple pricing vendors and internal models.