Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 87,910	$ 65,981	$ 35,194
Unrealized gain on interest rate swap contracts, net of deferred income tax expense of $12,228, 3,742 and $4,128 for the years ended December 31, 2016, 2015, and 2014, respectively	15,990	6,058	6,220
Foreign currency translation adjustments, net of deferred income tax (benefit) of $(2,548) and $(1,565) for the years ended December 31, 2016 and 2015, respectively	(34,999)	(11,177)	(16,273)
Other comprehensive (loss)	(19,009)	(5,119)	(10,053)
Total comprehensive income	68,901	60,862	25,141
Less: comprehensive loss attributable to noncontrolling interests	(99)	(438)	(1,987)
Comprehensive income attributable to controlling interests	$ 69,000	$ 61,300	$ 27,128