Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Components of comprehensive income
Net income	$ 6,101	$ 5,544	$ 6,033	$ 5,128	$ 11,645	$ 11,161
Mark to market of foreign exchange hedges	9		32		1	6
Deferred income tax (expense) benefit	(2)		(7)			(1)
Comprehensive income	$ 6,108	$ 5,538	$ 6,058	$ 5,108	$ 11,646	$ 11,166
Foreign exchange hedges liabilities							$ (1)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Fair value as of the balance sheet date of all foreign currency derivative liabilities designated as cash flow hedging instruments.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount before tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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