Income Taxes (Details 4) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance, beginning of year	$ 51,851	$ 14,967	$ 15,401
Increases related to current year tax positions	17,264	40,840	1,446
Increases related to prior year tax positions	5,781	1,066	299
Decreases related to prior year tax positions	(759)	(610)	(724)
Lapse of statute of limitations	(1,260)	(4,070)	(1,455)
Settlements	(986)	(342)	0
Change due to Currency Translation	5,384	0	0
Balance, end of year	77,275	$ 51,851	$ 14,967
Accrued interest and penalties	$ 7,000

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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