Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income		$ 49,429	$ 45,027	$ 88,247	$ 83,330
Other comprehensive (loss) income, net of tax
Unrealized gain (loss) on hedging activities, net of tax (1)	[1]	415	(544)	811	(461)
Foreign currency translation adjustments, net of tax (2)	[2]	(65,360)	41,562	(38,407)	60,172
Defined benefit pension and other postretirement benefits, net of tax (3)	[3]	3,025	671	6,189	1,936
Total other comprehensive (loss) income, net of tax		(61,920)	41,689	(31,407)	61,647
Total comprehensive (loss) income		(12,491)	86,716	56,840	144,977
Unrealized (loss) income on hedging activities, tax		131	(250)	279	(212)
Foreign currency translation adjustment, tax		(324)	314	(162)	380
Defined benefit pension and other postretirement benefits, tax		$ 806	$ 989	$ 2,063	$ 1,890

[1] Net of tax of $131 and $(250) for the three months ended June 30, 2018 and 2017, respectively, and $279 and $(212) for the six months ended June 30, 2018 and 2017, respectively.

[2] Net of tax of $(324) and $314 for the three months ended June 30, 2018 and 2017, respectively, and $(162) and $380 for the six months ended June 30, 2018 and 2017, respectively.

[3] Net of tax of $806 and $989 for the three months ended June 30, 2018 and 2017, respectively, and $2,063 and $1,890 for the six months ended June 30, 2018 and 2017, respectively.