Investments - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Debt maturity securities, amortized cost	$ 123,324	$ 122,678
Debt securities, gross unrealized gain	1,404	248
Debt securities, gross unrealized loss	(610)	(2,486)
Total debt securities	124,118	120,440
U.S. Government
Debt Securities, Available-for-sale [Line Items]
Debt maturity securities, amortized cost	14,787	15,360
Debt securities, gross unrealized gain	51	3
Debt securities, gross unrealized loss	(18)	(178)
Total debt securities	14,820	15,185
State and local government
Debt Securities, Available-for-sale [Line Items]
Debt maturity securities, amortized cost	14,467	15,847
Debt securities, gross unrealized gain	461	115
Debt securities, gross unrealized loss	(4)	(174)
Total debt securities	14,924	15,788
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Debt maturity securities, amortized cost	32,281	30,423
Debt securities, gross unrealized gain	600	74
Debt securities, gross unrealized loss	(23)	(651)
Total debt securities	32,858	29,846
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt maturity securities, amortized cost	21,718	24,468
Debt securities, gross unrealized gain	73	24
Debt securities, gross unrealized loss	(75)	(208)
Total debt securities	21,716	24,284
Mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt maturity securities, amortized cost	32,409	30,377
Debt securities, gross unrealized gain	85	18
Debt securities, gross unrealized loss	(481)	(1,155)
Total debt securities	32,013	29,240
Commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt maturity securities, amortized cost	4,673	4,025
Debt securities, gross unrealized gain	113	5
Debt securities, gross unrealized loss	(9)	(77)
Total debt securities	4,777	3,953
Collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Debt maturity securities, amortized cost	2,989	2,178
Debt securities, gross unrealized gain	21	9
Debt securities, gross unrealized loss	0	(43)
Total debt securities	$ 3,010	$ 2,144

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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Amount, before tax, of unrealized loss 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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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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