CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 71,441	$ 63,799	$ 217,766	$ 187,660
Other comprehensive income (loss)
Reclassification adjustments for derivatives, net of tax	1,141	1,174	3,453	3,551
Pension and other postretirement adjustments, net of tax	1,614	696	2,570	2,907
Cumulative translation adjustment	(55,688)	28,835	(41,530)	5,726
Other comprehensive income (loss)	(52,933)	30,705	(35,507)	12,184
Comprehensive income	$ 18,508	$ 94,504	$ 182,259	$ 199,844