Accumulated Other Comprehensive Loss - Schedule of AOCI (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Increase (Decrease} In Accumulated Other Comprehensive Income (Loss), Net Of Tax1 [Roll Forward]
Beginning balance	$ 143,544	$ 138,194
Other comprehensive gain (loss) before reclassifications	1,567	(1,155)
Amounts reclassified from accumulated other comprehensive loss	27	40
Total other comprehensive gain (loss) income	1,594	(1,115)
Reclassification from adoption of 2016-01		0
Ending balance	147,036	138,113
Net Unrealized Gain (Loss) on Available for Sale Securities
Increase (Decrease} In Accumulated Other Comprehensive Income (Loss), Net Of Tax1 [Roll Forward]
Beginning balance	(1,360)	(54)
Other comprehensive gain (loss) before reclassifications	1,567	(1,155)
Amounts reclassified from accumulated other comprehensive loss	(10)	6
Total other comprehensive gain (loss) income	1,557	(1,149)
Ending balance	197	(1,740)
Defined Benefit Plan
Increase (Decrease} In Accumulated Other Comprehensive Income (Loss), Net Of Tax1 [Roll Forward]
Beginning balance	(5,276)	(4,920)
Other comprehensive gain (loss) before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive loss	37	34
Total other comprehensive gain (loss) income	37	34
Ending balance	(5,239)	(4,886)
AOCI Attributable to Parent
Increase (Decrease} In Accumulated Other Comprehensive Income (Loss), Net Of Tax1 [Roll Forward]
Beginning balance	(6,636)	(4,974)
Total other comprehensive gain (loss) income	1,594	(1,115)
Reclassification from adoption of 2016-01		(537)
Ending balance	(5,042)	(6,626)
Accounting Standards Update 2016-01
Increase (Decrease} In Accumulated Other Comprehensive Income (Loss), Net Of Tax1 [Roll Forward]
Reclassification from adoption of 2016-01	0	(537)
Accounting Standards Update 2016-01 \| Net Unrealized Gain (Loss) on Available for Sale Securities
Increase (Decrease} In Accumulated Other Comprehensive Income (Loss), Net Of Tax1 [Roll Forward]
Reclassification from adoption of 2016-01	0	(537)
Accounting Standards Update 2016-01 \| Defined Benefit Plan
Increase (Decrease} In Accumulated Other Comprehensive Income (Loss), Net Of Tax1 [Roll Forward]
Reclassification from adoption of 2016-01	$ 0	$ 0

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 of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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

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

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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