Accumulated Other Comprehensive (Loss) Income - Amount of Income Tax Benefit (Expense) Allocated to Component of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Equity [Abstract]
Foreign Currency Translation, Other comprehensive (loss) income, before tax	$ (9,550)	$ 56,156	$ (95,517)	$ 200,366
Foreign Currency Translation, Income tax benefit (expense)	1	23	2	(1,063)
Foreign currency translation, Other comprehensive (loss) income, net of tax	(9,549)	56,179	(95,515)	199,303
Pension and Postretirement Benefits, Other comprehensive (loss) income, before tax	13	0	43	10
Pension and Postretirement Benefits, Income tax benefit (expense)	(2)	(7)	(6)	(8)
Pension and Postretirement Benefits, Other comprehensive (loss) income, net of tax	11	(7)	37	2
Net investment hedge, Other comprehensive (loss) income, before tax	(4,704)	(15,266)	6,426	(59,292)
Net investment hedge, Income tax benefit (expense)	1,083	5,585	(1,479)	21,692
Net investment hedge, Other comprehensive (loss) income, net of tax	(3,621)	(9,681)	4,947	(37,600)
Interest rate swap, Other comprehensive (loss) income, before tax	834	834	2,502	2,502
Interest rate swap, Income tax benefit (expense)	(192)	(305)	(576)	(915)
Interest rate swap, Other comprehensive (loss) income, net of tax	$ 642	$ 529	$ 1,926	$ 1,587