Accumulated Other Comprehensive Income/(Loss) OCI Attributable to Noncontrolling Interest (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Noncontrolling Interest [Abstract]
Net income attributable to noncontrolling interest	$ 2,720	$ 3,145	$ 8,090	$ 6,317
Foreign currency translation adjustment, net of tax, portion attributable to noncontrolling interest	(4,804)	4,972	(17,647)	18,642
Net unrealized gain/(loss) on qualifying cash flow hedges, net of tax	(95)	383	62	(296)
Comprehensive income attributable to noncontrolling interest	(2,179)	8,500	(9,495)	24,663
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax, Portion Attributable to Noncontrolling Interest	$ 41	$ (164)	$ (26)	$ 127

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

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss), attributable to noncontrolling interests.

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Amount of tax expense (benefit), after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss), attributable to noncontrolling interests.

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Amount after 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, attributable to noncontrolling interests.

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