CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 69,585	$ 71,777	$ 135,539	$ 146,325
Other comprehensive income (loss)
Reclassification adjustments for derivatives, net of tax	1,126	1,155	2,256	2,312
Pension and other postretirement adjustments, net of tax	820	517	1,600	956
Cumulative translation adjustment	23,743	13,874	(32,894)	14,158
Other comprehensive income (loss)	25,689	15,546	(29,038)	17,426
Comprehensive income	$ 95,274	$ 87,323	$ 106,501	$ 163,751