Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 02, 2019	Mar. 03, 2018	Mar. 02, 2019	Mar. 03, 2018
Net Income Per Share [Abstract]
Net income attributable to MSC Industrial as reported	$ 68,424	$ 117,552	$ 142,656	$ 177,137
Less: Distributed net income available to participating securities	(5)	(22)	(24)	(59)
Less: Undistributed net income available to participating securities	(15)	(105)	(46)	(197)
Undistributed and distributed net income available to common shareholders	68,404	117,425	142,586	176,881
Add: Undistributed net income allocated to participating securities	15	105	46	197
Less: Undistributed net income reallocated to participating securities	(15)	(104)	(46)	(196)
Undistributed and distributed net income available to common shareholders	$ 68,404	$ 117,426	$ 142,586	$ 176,882
Weighted average shares outstanding for basic net income per share	55,139	56,439	55,320	56,363
Effect of dilutive securities	223	453	299	335
Weighted average shares outstanding for diluted net income per share	55,362	56,892	55,619	56,698
Basic	$ 1.24	$ 2.08	$ 2.58	$ 3.14
Diluted	$ 1.24	$ 2.06	$ 2.56	$ 3.12
Potentially dilutive securities	1,123		718