Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 48,396	$ 55,714
Other comprehensive income, net of tax:
Foreign currency translation adjustments	(3,662)	10,978
Unrealized gain (loss) on derivative instruments	(2,469)	4,529
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	(606)	85
Comprehensive income	41,641	71,306
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	18	0
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ 41,659	$ 71,306