Basis Of Presentation (Policy)	3 Months Ended
Nov. 28, 2020
Basis Of Presentation [Abstract]
Principles Of Consolidation	Principles of Consolidation The Condensed Consolidated Financial Statements include the accounts of MSC Industrial Direct Co., Inc., its wholly owned subsidiaries and entities in which it maintains a controlling financial interest. All significant intercompany balances and transactions have been eliminated in consolidation.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements Effective August 30, 2020, the Company adopted the Financial Accounting Standards Board (“FASB”) Accounting Standard Update (“ASU”) 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. ASU 2016-13 requires that an entity measure impairment of certain financial instruments, including trade receivables, based on expected losses rather than incurred losses. The adoption of this guidance did not have a material impact on the Company’s condensed consolidated financial statements. Effective August 30, 2020, the Company adopted ASU 2017-04, Intangibles – Goodwill and Other. This standard eliminates the second step from the goodwill impairment test and instead requires an entity to perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An impairment charge would be recognized for the amount by which the carrying amount exceeds the reporting unit's fair value, not to exceed the total amount of goodwill allocated to that reporting unit. The adoption of this guidance did not have a material impact on the Company’s condensed consolidated financial statements. The Company will apply this guidance prospectively to its annual and interim goodwill impairment tests.
Accounting Pronouncements Not Yet Adopted	Accounting Pronouncements Not Yet Adopted In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting, which provides temporary optional expedients and exceptions to accounting guidance on contract modifications and hedge accounting to ease entities financial reporting burdens as the market transitions from the London Interbank Offered Rate (“LIBOR”) and other interbank offered rates to alternative reference rates. The guidance was effective upon issuance and may be applied prospectively to contract modifications made and hedging relationships entered into or evaluated on or before December 31, 2022. The Company is currently evaluating the impact of the new guidance on its consolidated financial statements. In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which removes certain exceptions related to the approach for intraperiod tax allocations, the calculation of income taxes in interim periods, and the recognition of deferred taxes for taxable goodwill. The guidance is effective for fiscal years beginning after December 15, 2020 and for interim periods within those years, with early adoption permitted. The new standard is effective for the Company for its fiscal year 2022. The Company is currently evaluating the impact of the new guidance on its consolidated financial statements. Other pronouncements issued by the FASB or other authoritative accounting standards groups with future effective dates are either not applicable or are not expected to have a material impact on the Company’s condensed consolidated financial statements.

Basis Of Presentation (Policy)

3 Months Ended

Nov. 28, 2020

Principles of Consolidation

The Condensed Consolidated Financial Statements include the accounts of MSC Industrial Direct Co., Inc., its wholly owned subsidiaries and entities in which it maintains a controlling financial interest. All significant intercompany balances and transactions have been eliminated in consolidation.

Recently Adopted Accounting Pronouncements

Effective August 30, 2020, the Company adopted the Financial Accounting Standards Board (“FASB”) Accounting Standard Update (“ASU”) 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. ASU 2016-13 requires that an entity measure impairment of certain financial instruments, including trade receivables, based on expected losses rather than incurred losses. The adoption of this guidance did not have a material impact on the Company’s condensed consolidated financial statements.

Effective August 30, 2020, the Company adopted ASU 2017-04, Intangibles – Goodwill and Other. This standard eliminates the second step from the goodwill impairment test and instead requires an entity to perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An impairment charge would be recognized for the amount by which the carrying amount exceeds the reporting unit's fair value, not to exceed the

total amount of goodwill allocated to that reporting unit. The adoption of this guidance did not have a material impact on the Company’s condensed consolidated financial statements. The Company will apply this guidance prospectively to its annual and interim goodwill impairment tests.

Accounting Pronouncements Not Yet Adopted

In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting, which provides temporary optional expedients and exceptions to accounting guidance on contract modifications and hedge accounting to ease entities financial reporting burdens as the market transitions from the London Interbank Offered Rate (“LIBOR”) and other interbank offered rates to alternative reference rates. The guidance was effective upon issuance and may be applied prospectively to contract modifications made and hedging relationships entered into or evaluated on or before December 31, 2022. The Company is currently evaluating the impact of the new guidance on its consolidated financial statements.

In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which removes certain exceptions related to the approach for intraperiod tax allocations, the calculation of income taxes in interim periods, and the recognition of deferred taxes for taxable goodwill. The guidance is effective for fiscal years beginning after December 15, 2020 and for interim periods within those years, with early adoption permitted. The new standard is effective for the Company for its fiscal year 2022. The Company is currently evaluating the impact of the new guidance on its consolidated financial statements.

Other pronouncements issued by the FASB or other authoritative accounting standards groups with future effective dates are either not applicable or are not expected to have a material impact on the Company’s condensed consolidated financial statements.