Restructuring and Other Costs (Narrative) (Details)	12 Months Ended
Aug. 28, 2021 item
Restructuring and Other Costs [Abstract]
Number of locations closed	73

Restructuring and Related Cost, Number of locations closed

No definition available.

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Namespace Prefix:	msm_
Data Type:	xbrli:positiveIntegerItemType
Balance Type:	na
Period Type:	duration