Nature of Business and Significant Accounting Policies (Details 7) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Changes from Accumulated Other Comprehensive income [Abstract]
Pension plans, beginning balance	$ (344)
Pension plans adjustment, before reclassification	(338)
Pension plans, reclassification	0
Pension plans adjustment, after reclassification	(338)
Pension plans, ending balalnce	(682)	$ (344)
Cash flow hedges, reclassification	0
Foreign currency translation, beginning balance	(113,012)
Foreign currency translation adjustment	(35,394)
Foreign currency translation, ending balance	(148,406)	(113,012)
Accumulated other comprehensive earnings, beginning balance	(113,360)
Other comprehensive earnings, before reclassifications	(35,732)
Other comprehensive earnings, reclassification	0
Other comprehensive earnings, after adjustment	(35,732)
Other comprehensive income (loss), available-for-sale before reclassification, net of tax	0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax	0
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, after Tax	(4)	(4)
Accumulated other comprehensive earnings, ending balance	$ (149,092)	$ (113,360)

Changes from Accumulated Other Comprehensive income [Abstract]

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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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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities and unrealized holding gain (loss) related to transfers of securities into the available-for-sale classification and out of the held-to-maturity classification.

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