CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 113,209	$ 107,126	$ 223,477	$ 206,084
Other comprehensive income (loss):
Reclassification adjustments for derivatives, net of tax	1,224	1,259	2,451	2,520
Pension and other postretirement adjustments, net of tax	1,256	1,296	2,518	2,709
Cumulative translation adjustment	2,628	(62,645)	(653)	(35,067)
Other comprehensive income (loss)	5,108	(60,090)	4,316	(29,838)
Comprehensive income	$ 118,317	$ 47,036	$ 227,793	$ 176,246