Document And Entity Information - shares	9 Months Ended
	Jun. 03, 2017	Jun. 30, 2017
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 03, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q3
Entity Registrant Name	MSC INDUSTRIAL DIRECT CO INC
Entity Central Index Key	0001003078
Current Fiscal Year End Date	--09-02
Entity Filer Category	Large Accelerated Filer
Class A Common Stock [Member]
Entity Common Stock, Shares Outstanding		45,102,339
Class B Common Stock [Member]
Entity Common Stock, Shares Outstanding		11,850,636