Comprehensive Income (Details 2) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Foreign Currency Translation Adjustments, Beginning balance	$ (6,901)
Foreign Currency Translation Adjustments, Other comprehensive (loss) income before reclassifications	130
Foreign Currency Translation Adjustments, Amounts reclassified from accumulated other comprehensive loss	0
Foreign Currency Translation Adjustments, Net current period other comprehensive loss (income)	130
Foreign Currency Translation Adjustments, Ending balance	(6,771)
Defined Benefit Pension Items, Beginning balance	(14,671)
Defined Benefit Pension Items, Other comprehensive loss before reclassifications	0
Defined Benefit Pension Items, Amounts reclassified from accumulated other comprehensive loss	108	$ 118
Defined Benefit Pension Items, Net current period other comprehensive loss (income)	108
Defined Benefit Pension Items, Ending balance	(14,563)
Beginning balance	(21,572)
Other comprehensive (loss) income before reclassifications	130
Amounts reclassified from accumulated other comprehensive loss	108
Net current period other comprehensive loss (income)	238
Ending balance	$ (21,334)

Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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The increase (decrease) in cumulative translation adjustment before transfers included in determining net income.

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Amount after tax, before 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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