Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Changes in balances of each component of accumulated other comprehensive income, net of taxes [Roll Forward]
Beginning Balance			$ 105,506	$ 102,492
Total other comprehensive income, net of tax	$ (793)	$ 4,111	1,391	5,088
Ending Balance	107,536	108,049	107,536	108,049
AOCI Attributable to Parent [Member]
Changes in balances of each component of accumulated other comprehensive income, net of taxes [Roll Forward]
Beginning Balance			5,830	4,584
Total other comprehensive income, net of tax			1,391	5,088
Ending Balance	7,221	$ 9,672	7,221	$ 9,672
Unrealized Gains on Available-for-Sale Securities [Member]
Changes in balances of each component of accumulated other comprehensive income, net of taxes [Roll Forward]
Beginning Balance			5,830
Other comprehensive income before reclassifications			2,872
Amounts reclassified from accumulated other comprehensive income			(1,481)
Total other comprehensive income, net of tax			1,391
Ending Balance	$ 7,221		$ 7,221

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 after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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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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