Condensed Consolidated Statements Of Shareholders' Equity - USD ($) $ in Thousands	Class A Common Stock [Member] Common Stock [Member]	Class A Common Stock [Member] Retained Earnings [Member]	Class A Common Stock [Member] Treasury Stock [Member]	Class A Common Stock [Member]	Class B Common Stock [Member] Common Stock [Member]	Class B Common Stock [Member] Retained Earnings [Member]	Class B Common Stock [Member]	Additional Paid-In-Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Treasury Stock [Member]	Total Shareholders' Equity Attributable to MSC Industrial [Member]	Noncontrolling Interest [Member]	Total
Balance, Value at Sep. 01, 2018	$ 55				$ 10			$ 657,749	$ 1,325,822	$ (19,634)	$ (576,748)
Issuance of Noncontrolling Interest in MSC Mexico													$ 4,637
Capital Contributions													1,022
Foreign Currency Translation Adjustment										(3,096)			(146)	$ (3,242)
Net Income									222,257				(81)	222,257
Associate Incentive Plans								29,812			1,769
Repurchase and retirement of common stock, Value	(1)	$ (48,439)						(11,887)
Repurchases of common stock, Value			$ (24,137)
Cash dividends on common stock		(85,042)				$ (19,266)
Dividend equivalents declared, net of cancellations									(781)
Balance, Value at Jun. 01, 2019	54				10			675,674	1,394,551	(22,730)	(599,116)	$ 1,448,443	5,432	1,453,875
Dividends declared per common share				$ 1.89			$ 1.89
Balance, Value at Mar. 02, 2019	54				10			670,047	1,349,972	(20,237)	(599,603)		5,602
Foreign Currency Translation Adjustment										(2,493)			(83)	(2,576)
Net Income									79,601				(87)	79,601
Associate Incentive Plans								5,627			526
Repurchase and retirement of common stock, Value
Repurchases of common stock, Value			(39)
Cash dividends on common stock		(28,335)				(6,422)
Dividend equivalents declared, net of cancellations									(265)
Balance, Value at Jun. 01, 2019	54				10			675,674	1,394,551	(22,730)	(599,116)	1,448,443	5,432	1,453,875
Dividends declared per common share				0.63			0.63
Balance, Value at Aug. 31, 2019	46				10			659,226	946,651	(22,776)	(104,607)		5,329	1,483,879
Foreign Currency Translation Adjustment										(2,806)			(441)	(3,247)
Net Income									198,621				501	198,621
Associate Incentive Plans	1							26,756			3,254
Repurchase and retirement of common stock, Value
Repurchases of common stock, Value			(3,236)
Cash dividends on common stock		(329,052)				(73,433)
Dividend equivalents declared, net of cancellations									(3,752)
Balance, Value at May. 30, 2020	47				10			685,982	739,035	(25,582)	(104,589)	1,294,903	5,389	1,300,292
Dividends declared per common share				7.25			7.25
Balance, Value at Feb. 29, 2020	47				10			681,657	703,396	(22,053)	(105,758)		5,514
Foreign Currency Translation Adjustment										(3,529)			(536)	(4,065)
Net Income									77,703				411	77,703
Associate Incentive Plans								4,325			1,197
Repurchase and retirement of common stock, Value
Repurchases of common stock, Value			$ (28)
Cash dividends on common stock		$ (34,129)				$ (7,541)
Dividend equivalents declared, net of cancellations									(394)
Balance, Value at May. 30, 2020	$ 47				$ 10			$ 685,982	$ 739,035	$ (25,582)	$ (104,589)	$ 1,294,903	$ 5,389	$ 1,300,292
Dividends declared per common share				$ 0.75			$ 0.75