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. 02, 2017	$ 54				$ 12			$ 626,995	$ 1,168,812	$ (17,263)	$ (553,470)
Exchange of Class B common stock for Class A common stock, value	1				(2)
Associate Incentive Plans								36,404			1,624
Repurchases of common stock, Value			$ (25,384)
Cash dividends on common stock		$ (74,285)				$ (18,348)
Dividend equivalents declared, net of cancellations									(597)
Foreign Currency Translation Adjustment										(1,705)				$ (1,705)
Net income									256,206					256,206
Balance, Value at Jun. 02, 2018	55				10			663,399	1,331,788	(18,968)	(577,230)	$ 1,399,054		1,399,054
Dividends declared per common share				$ 1.64			$ 1.64
Balance, Value at Mar. 03, 2018	55				11			652,440	1,285,681	(18,079)	(574,073)
Exchange of Class B common stock for Class A common stock, value					(1)
Associate Incentive Plans								10,959			499
Repurchases of common stock, Value			$ (3,656)
Cash dividends on common stock		(26,598)				(6,162)
Dividend equivalents declared, net of cancellations									(202)
Foreign Currency Translation Adjustment										(889)				(889)
Net income									79,069					79,069
Balance, Value at Jun. 02, 2018	55				10			663,399	1,331,788	(18,968)	(577,230)	1,399,054		1,399,054
Dividends declared per common share				0.58			0.58
Balance, Value at Sep. 01, 2018	55				10			657,749	1,325,822	(19,634)	(576,748)			1,387,254
Associate Incentive Plans								29,812			1,769
Repurchases of common stock, Shares			316,000
Repurchases of common stock, Value			$ (24,137)
Repurchase and retirement of common stock, Value	(1)							(11,887)	(48,439)
Cash dividends on common stock		(85,042)				(19,266)
Dividend equivalents declared, net of cancellations									(781)
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)	222,176
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
Associate Incentive Plans								5,627			526
Repurchases of common stock, Shares			500
Repurchases of common stock, Value			$ (39)
Cash dividends on common stock		$ (28,335)				$ (6,422)
Dividend equivalents declared, net of cancellations									(265)
Foreign Currency Translation Adjustment										(2,493)			(83)	(2,576)
Net income									79,601				(87)	79,514
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