Investments - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Debt Securities:
Fixed maturity securities, amortized cost	$ 137,025	$ 137,004
Fixed maturity securities, gross unrealized gain	252	531
Fixed maturity securities, gross unrealized loss	(2,565)	(999)
Fixed maturity securities, estimated fair value	134,711	136,536
Equity Securities
Equity securities, amortized cost	8,664	8,629
Equity securities, gross unrealized gain		1,240
Equity securities, gross unrealized loss		(182)
Equity securities, estimated fair value	9,425	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:
Fixed maturity securities, amortized cost	15,896	17,179
Fixed maturity securities, gross unrealized gain	4	10
Fixed maturity securities, gross unrealized loss	(222)	(99)
Fixed maturity securities, estimated fair value	15,678	17,090
State and local government
Debt Securities:
Fixed maturity securities, amortized cost	16,668	17,302
Fixed maturity securities, gross unrealized gain	85	255
Fixed maturity securities, gross unrealized loss	(201)	(54)
Fixed maturity securities, estimated fair value	16,552	17,503
Corporate debt
Debt Securities:
Fixed maturity securities, amortized cost	38,806	38,947
Fixed maturity securities, gross unrealized gain	92	170
Fixed maturity securities, gross unrealized loss	(651)	(209)
Fixed maturity securities, estimated fair value	38,247	38,908
Asset-backed securities
Debt Securities:
Fixed maturity securities, amortized cost	25,331	23,539
Fixed maturity securities, gross unrealized gain	37	36
Fixed maturity securities, gross unrealized loss	(110)	(35)
Fixed maturity securities, estimated fair value	25,258	23,540
Mortgage-backed securities
Debt Securities:
Fixed maturity securities, amortized cost	33,981	33,942
Fixed maturity securities, gross unrealized gain	22	38
Fixed maturity securities, gross unrealized loss	(1,242)	(522)
Fixed maturity securities, estimated fair value	32,761	33,458
Commercial mortgage-backed securities
Debt Securities:
Fixed maturity securities, amortized cost	3,935	3,532
Fixed maturity securities, gross unrealized gain	0	3
Fixed maturity securities, gross unrealized loss	(85)	(44)
Fixed maturity securities, estimated fair value	3,850	3,491
Collateralized mortgage obligations
Debt Securities:
Fixed maturity securities, amortized cost	2,408	2,563
Fixed maturity securities, gross unrealized gain	12	19
Fixed maturity securities, gross unrealized loss	(54)	(36)
Fixed maturity securities, estimated fair value	$ 2,365	$ 2,546

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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