Other Comprehensive Income (Loss) - Reclassification out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance			$ 191,542	$ 181,321
Ending balance	$ 208,489	$ 184,661	208,489	184,661
Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	37	(147)	37	(147)
Amortization of unrecognized transition obligation	0	0	0	0
Change in unamortized net actuarial gain (loss)	0	0	0	0
Related deferred taxes	0	0	0	0
Ending balance	$ 37	$ (147)	$ 37	$ (147)

Reclassification Adjustment out of Accumulated Other Comprehensive Income [Roll Forward]

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- Definition

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

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- Definition

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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- Definition

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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