CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS - 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 earnings	$ 106,959	$ 179,445	$ 289,812	$ 371,089
Other comprehensive earnings:
Foreign currency translation adjustments, net of reclassification (see Note 5)	46,543	(6,915)	75,846	44,575
Postretirement benefit plan reclassification, net of tax benefit of $878, $631, and $1,757, $1,262, respectively	(1,400)	(1,009)	(2,798)	(2,018)
Other	0	352	(12)	656
Comprehensive earnings, net of tax	152,102	171,873	362,848	414,302
Less: Comprehensive earnings attributable to noncontrolling interest
Net earnings	9,038	6,769	17,147	11,700
Foreign currency translation adjustments	(1,186)	8,729	4,346	14,433
Comprehensive earnings attributable to W.W. Grainger, Inc.	$ 144,250	$ 156,375	$ 341,355	$ 388,169

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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