Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 141,096	$ 225,037	$ 261,006
OTHER COMPREHENSIVE (LOSS)/INCOME:
Foreign currency translation adjustment	(47,349)	(86,968)	(56,059)
Net unrealized loss on qualifying cash flow hedges, net of tax benefit/(provision)	(5,666)	(3,837)	(23,473)
Changes in pension and other postretirement benefit obligations, net of tax benefit/(provision)	(30,953)	9,600	1,191
Other comprehensive loss	(83,968)	(81,205)	(78,341)
COMPREHENSIVE INCOME	57,128	143,832	182,665
Less: Comprehensive income attributable to noncontrolling interest	8,508	0	251
COMPREHENSIVE INCOME ATTRIBUTABLE TO G&W	$ 48,620	$ 143,832	$ 182,414