Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 48,128	$ 48,399	$ 75,417	$ 75,418
OTHER COMPREHENSIVE INCOME:
Foreign currency translation adjustment	30,899	(32,611)	67,152	(1,491)
Net unrealized loss on qualifying cash flow hedges, net of tax (provision)/benefit	(604)	(6,806)	(98)	(16,237)
Changes in pension and other postretirement benefits, net of tax (provision)/benefit	(1,294)	1,000	(2,187)	2,924
Other comprehensive income/(loss)	29,001	(38,417)	64,867	(14,804)
COMPREHENSIVE INCOME	77,129	9,982	140,284	60,614
Less: Comprehensive income attributable to noncontrolling interest	3,078	0	16,163	0
COMPREHENSIVE INCOME ATTRIBUTABLE TO G&W	$ 74,051	$ 9,982	$ 124,121	$ 60,614

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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