Other Comprehensive Income (Loss) - Summary of Available for Sale Securities Activity (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			$ 172,521	$ 167,498
Other comprehensive income (loss)	$ (263)	$ (1,090)	(29)	1,631
Ending balance	179,882	175,994	179,882	175,994
Accumulated Net Investment Gain (Loss) Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(585)	4,000	(935)	1,123
Unrealized gains (losses) arising during the period	99	(1,851)	640	3,106
Reclassification of realized gains during the period	(468)	(137)	(471)	(668)
Related deferred taxes	129	696	(59)	(853)
Other comprehensive income (loss)	(240)	(1,292)	110	1,585
Ending balance	$ (825)	$ 2,708	$ (825)	$ 2,708

Accumulated Other Comprehensive Income (Loss) [Roll Forward]

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Amount before tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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