Other Comprehensive Income (Loss), Summary of Transfer of AFS Securities to HTM (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Balance	$ 175,994	$ 174,788	$ 171,544	$ 167,498	$ 167,141	$ 163,809	$ 163,516	$ 161,554	$ 167,498	$ 161,554	$ 146,098
Other comprehensive income (loss)	(2,489)	(1,090)	880	1,841	(1,239)	1,315	(1,608)	38	(858)	(1,494)	8,752
Balance	172,521	$ 175,994	$ 174,788	171,544	167,498	$ 167,141	$ 163,809	163,516	172,521	167,498	161,554
Accumulated Net Gain (Loss) on Securities Transferred from Available-for-Sale to Held-to-Maturity
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Balance				$ (112)				$ (48)	(112)	(48)	0
Unrealized gains (losses) during the period									0	0	(23)
Amortization of unrealized losses									(26)	(98)	(51)
Related deferred taxes									9	34	26
Other comprehensive income (loss)									(17)	(64)	(48)
Balance	$ (129)				$ (112)				$ (129)	$ (112)	$ (48)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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