Investments - Schedule of Realized Gain (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Debt and Equity Securities, Gain (Loss) [Abstract]
Gross realized gains	$ 73	$ 48	$ 565	$ 147
Gross realized losses	(511)	(180)	(792)	(630)
Net realized gains (losses)	(438)	(132)	(227)	(483)
Fair Value at Sale
Fair value at sale	4,913	6,329	8,063	18,915
Fair value at sale	38,091	13,948	70,319	37,496
Net fair value at sale	43,004	20,277	78,382	56,411
Fixed Maturities
Debt and Equity Securities, Gain (Loss) [Abstract]
Gross realized gains	14	41	56	140
Gross realized losses	(511)	(170)	(792)	(620)
Fair Value at Sale
Fair value at sale	4,706	6,310	6,881	18,896
Fair value at sale	38,091	13,848	70,319	37,396
Equity Securities
Debt and Equity Securities, Gain (Loss) [Abstract]
Gross realized gains	59	7	509	7
Gross realized losses	0	(10)	0	(10)
Fair Value at Sale
Fair value at sale	207	19	1,182	19
Fair value at sale	$ 0	$ 100	$ 0	$ 100