Investments - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	$ 125,018	$ 137,004
Fixed maturity securities, gross unrealized gain	182	531
Fixed maturity securities, gross unrealized loss	(3,204)	(999)
Fixed maturity securities	121,996	136,536
Equity securities, amortized cost	8,890	8,629
Equity securities, gross unrealized gain		1,240
Equity securities, gross unrealized loss		(182)
Equity securities, estimated fair value	9,832	9,687
Securities, cost or amortized cost		145,633
Securities, gross unrealized gain		1,771
Securities, gross unrealized loss		(1,181)
Securities, estimated fair value		146,223
U.S. Government
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	15,809	17,179
Fixed maturity securities, gross unrealized gain	1	10
Fixed maturity securities, gross unrealized loss	(307)	(99)
Fixed maturity securities	15,503	17,090
State and local government
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	16,004	17,302
Fixed maturity securities, gross unrealized gain	57	255
Fixed maturity securities, gross unrealized loss	(305)	(54)
Fixed maturity securities	15,756	17,503
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	31,742	38,947
Fixed maturity securities, gross unrealized gain	86	170
Fixed maturity securities, gross unrealized loss	(706)	(209)
Fixed maturity securities	31,122	38,908
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	24,006	23,539
Fixed maturity securities, gross unrealized gain	22	36
Fixed maturity securities, gross unrealized loss	(187)	(35)
Fixed maturity securities	23,841	23,540
Mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	31,320	33,942
Fixed maturity securities, gross unrealized gain	9	38
Fixed maturity securities, gross unrealized loss	(1,524)	(522)
Fixed maturity securities	29,805	33,458
Commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	3,890	3,532
Fixed maturity securities, gross unrealized gain	0	3
Fixed maturity securities, gross unrealized loss	(100)	(44)
Fixed maturity securities	3,790	3,491
Collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	2,247	2,563
Fixed maturity securities, gross unrealized gain	7	19
Fixed maturity securities, gross unrealized loss	(75)	(36)
Fixed maturity securities	$ 2,179	$ 2,546

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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