Other Comprehensive Income (Loss) - Summary of Available for Sale Securities Activity (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			$ 172,521	$ 167,498
Other comprehensive income	$ 174	$ 880	234	2,721
Ending balance	177,537	174,788	177,537	174,788
Accumulated Net Investment Gain (Loss) Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(934)	2,975	(935)	1,123
Unrealized gains arising during the period	536	1,570	541	4,957
Reclassification of realized (gains) losses during the period	0	5	(3)	(531)
Related deferred taxes	(187)	(550)	(188)	(1,549)
Other comprehensive income	349	1,025	350	2,877
Ending balance	$ (585)	$ 4,000	$ (585)	$ 4,000

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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