Investments - Available-for-sale Securities in Unrealized Loss Positions (Details) $ in Thousands	Mar. 31, 2017 USD ($) security	Dec. 31, 2016 USD ($) security
Available-for-sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Less than 12 months, number of issues | security	118	201
Greater than 12 months, number of issues | security	10	15
Number of Issues | security	128	216
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months, fair value	$ 62,605	$ 62,307
Greater than 12 months, fair value	1,738	4,341
Fair Value	64,343	66,648
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss [Abstract]
Less than 12 months, unrealized losses	(1,250)	(1,260)
Greater than 12 months, unrealized losses	(22)	(36)
Unrealized losses	$ (1,272)	$ (1,296)
Total fixed maturity securities available for sale
Available-for-sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Less than 12 months, number of issues | security	97	125
Greater than 12 months, number of issues | security	8	13
Number of Issues | security	105	138
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months, fair value	$ 61,564	$ 59,835
Greater than 12 months, fair value	1,667	4,275
Fair Value	63,231	64,110
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss [Abstract]
Less than 12 months, unrealized losses	(1,177)	(1,199)
Greater than 12 months, unrealized losses	(16)	(27)
Unrealized losses	$ (1,193)	$ (1,226)
U.S. Government obligations
Available-for-sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Less than 12 months, number of issues | security	12	15
Greater than 12 months, number of issues | security	0	0
Number of Issues | security	12	15
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months, fair value	$ 4,439	$ 4,539
Greater than 12 months, fair value	0	0
Fair Value	4,439	4,539
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss [Abstract]
Less than 12 months, unrealized losses	(35)	(36)
Greater than 12 months, unrealized losses	0	0
Unrealized losses	$ (35)	$ (36)
State and local government
Available-for-sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Less than 12 months, number of issues | security	19	29
Greater than 12 months, number of issues | security	1	1
Number of Issues | security	20	30
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months, fair value	$ 6,319	$ 8,217
Greater than 12 months, fair value	99	104
Fair Value	6,418	8,321
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss [Abstract]
Less than 12 months, unrealized losses	(161)	(202)
Greater than 12 months, unrealized losses	(2)	(3)
Unrealized losses	$ (163)	$ (205)
Corporate debt
Available-for-sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Less than 12 months, number of issues | security	19	22
Greater than 12 months, number of issues | security	3	7
Number of Issues | security	22	29
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months, fair value	$ 10,521	$ 9,031
Greater than 12 months, fair value	1,021	3,369
Fair Value	11,542	12,400
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss [Abstract]
Less than 12 months, unrealized losses	(227)	(239)
Greater than 12 months, unrealized losses	(8)	(15)
Unrealized losses	$ (235)	$ (254)
Commercial mortgage-backed and other asset-backed
Available-for-sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Less than 12 months, number of issues | security	47	59
Greater than 12 months, number of issues | security	4	5
Number of Issues | security	51	64
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months, fair value	$ 40,285	$ 38,048
Greater than 12 months, fair value	547	802
Fair Value	40,832	38,850
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss [Abstract]
Less than 12 months, unrealized losses	(754)	(722)
Greater than 12 months, unrealized losses	(6)	(9)
Unrealized losses	$ (760)	$ (731)
Common stocks
Available-for-sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Less than 12 months, number of issues | security	21	76
Greater than 12 months, number of issues | security	2	2
Number of Issues | security	23	78
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months, fair value	$ 1,041	$ 2,472
Greater than 12 months, fair value	71	66
Fair Value	1,112	2,538
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss [Abstract]
Less than 12 months, unrealized losses	(73)	(61)
Greater than 12 months, unrealized losses	(6)	(9)
Unrealized losses	$ (79)	$ (70)