Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 194,609	$ 241,811	$ 243,528
Other comprehensive income (loss), net of tax:
Foreign currency translations, net of tax of $3,071 in 2019 and $(4,992) in 2018	75,319	(52,299)	103,624
Net unrealized gain on cash flow hedges, net of tax of $49, $232, and $678, respectively	146	684	1,079
Net unrealized gain (loss) on available for sale securities, net of tax of $1,970, $(1,545), and $944, respectively	5,910	(5,002)	1,477
Adjustments to pension and postretirement plans, net of tax of ($1,270), $(13,508), and $3,089, respectively	(845)	(46,170)	12,185
Amortization of pension and postretirement costs, net of tax of $9,497, $21,675, and $13,936, respectively	28,288	64,999	26,828
Other comprehensive income (loss), net of tax	108,818	(37,788)	145,193
Comprehensive income	$ 303,427	$ 204,023	$ 388,721