Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Feb. 29, 2020	Mar. 02, 2019	Feb. 29, 2020	Mar. 02, 2019
Net Income Per Share [Abstract]
Net income attributable to MSC Industrial as reported	$ 55,500	$ 68,424	$ 120,918	$ 142,656
Less: Distributed net income available to participating securities		(5)	(24)	(24)
Less: Undistributed net income available to participating securities		(15)		(46)
Undistributed and distributed net income available to common shareholders	55,500	68,404	120,894	142,586
Add: Undistributed net income allocated to participating securities		15		46
Less: Undistributed net income reallocated to participating securities		(15)		(46)
Undistributed and distributed net income available to common shareholders	$ 55,500	$ 68,404	$ 120,894	$ 142,586
Weighted average shares outstanding for basic net income per share	55,467	55,139	55,371	55,320
Effect of dilutive securities	120	223	174	299
Weighted average shares outstanding for diluted net income per share	55,587	55,362	55,545	55,619
Basic	$ 1.00	$ 1.24	$ 2.18	$ 2.58
Diluted	$ 1.00	$ 1.24	$ 2.18	$ 2.56
Potentially dilutive securities	1,096	1,123	1,447	718