Available increase in aggregate amount borrowed

No definition available.

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Namespace Prefix:	msm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number Of Credit Facilities

+ References

No definition available.

+ Details

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

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Maximum amount borrowed under the credit facility at any time during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Period Type:

- Details

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Debt - Revolving Credit Facilities Narrative (Details)	1 Months Ended	6 Months Ended
Debt - Revolving Credit Facilities Narrative (Details)	Aug. 31, 2021 USD ($)	Mar. 04, 2023 USD ($) facility	Feb. 26, 2022 USD ($)	Sep. 03, 2022 USD ($)	Apr. 30, 2017 USD ($)	Jul. 31, 2016 USD ($)
Debt Instrument [Line Items]
Number of credit facilities \| facility		3
Proceeds from lines of credit		$ 208,000,000	$ 184,000,000
Committed Bank Facility
Debt Instrument [Line Items]
Outstanding balance		$ 50,000,000		$ 245,000,000
Amended Uncommitted Credit Facilities
Debt Instrument [Line Items]
Credit facility, expiration term		1 year
Line of credit facility, maximum amount outstanding during period		$ 203,000,000
Outstanding balance		200,000,000		$ 200,000,000
Proceeds from lines of credit		208,000,000
Repayment of loan facility		$ 403,000,000
Line of credit facility, interest rate at period end		5.39%		3.42%
Amended Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity					$ 600,000,000
Credit facility, expiration term	5 years
Amended Revolving Credit Facility [Member] \| Letter of Credit
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 50,000,000
Outstanding balance		$ 5,269,000		$ 5,269,000
Amended Revolving Credit Facility [Member] \| Committed Bank Facility
Debt Instrument [Line Items]
Available increase in amount borrowed	$ 300,000,000
Senior Notes Series A \| Private Placement Debt
Debt Instrument [Line Items]
Debt instrument, face amount						$ 75,000,000
Interest rate		2.65%		2.65%		2.65%
Senior Notes Series B \| Private Placement Debt
Debt Instrument [Line Items]
Debt instrument, face amount						$ 100,000,000
Interest rate		2.90%				2.90%
Senior Notes Due June 11, 2025 \| Private Placement Debt
Debt Instrument [Line Items]
Debt instrument, face amount						$ 20,000,000
Interest rate		3.79%				3.79%
Senior notes, Due March 5, 2027 \| Private Placement Debt
Debt Instrument [Line Items]
Debt instrument, face amount						$ 50,000,000
Interest rate		2.60%				2.60%