Basis Of Presentation	3 Months Ended
Dec. 01, 2018
Basis Of Presentation [Abstract]
Basis Of Presentation	Note 1. Basis of Presentation The accompanying condensed consolidated financial statements include MSC Industrial Direct Co., Inc. (“MSC”) and all its subsidiaries (hereinafter referred to collectively as the “Company”). All intercompany balances and transactions have been eliminated in consolidation. The unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all the information and notes required by accounting principles generally accepted in the United States for complete financial statements. In the opinion of management, all adjustments considered necessary for a fair presentation (including normal recurring adjustments) have been included. Operating results for the thirteen-week period ended December 1, 2018 are not necessarily indicative of the results that may be expected for the fiscal year ending August 31, 2019. For further information, refer to the financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended September 1, 2018. The Company’s fiscal year ends on the Saturday closest to August 31 of each year. Unless the context requires otherwise, references to years contained herein pertain to the Company’s fiscal year. The Company’s 2019 fiscal year will be a 52-week accounting period that will end on August 31, 2019 and its 2018 fiscal year was a 52-week accounting period that ended on September 1, 2018. Recently Adopted Accounting Pronouncements Effective September 2, 2018, the Company adopted the Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers (Topic 606) as modified by subsequently issued ASUs 2015-14, 2016-08, 2016-10, 2016-12, 2016-20 and 2017-05. These ASUs outline a single comprehensive model for entities to use in the accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. Revenue continues to be recognized when products are shipped to the customer and the adoption of these ASUs, using the modified retrospective approach, had no impact to the Company’s opening retained earnings. The Company reports its sales net of estimated sales returns and sales incentives. Sales tax collected from customers is excluded from net sales. Additional information and disclosures required by this new standard are contained in Note 2, Revenue. Effective September 2, 2018, the Company adopted ASU 2017-01, which clarifies the definition of a business to assist entities with evaluating when a set of transferred assets and activities is considered a business. This standard will be applied to appropriate business combinations that occur beginning September 2, 2018. Accounting Pronouncements Not Yet Adopted In February 2016, the FASB issued its final standard on accounting for leases, ASU 2016-02, Leases (Topic 842). This standard requires that an entity that is a lessee recognize lease assets and lease liabilities on the balance sheet for all leases and disclose key information about leasing arrangements. This update is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, with earlier application permitted. The new standard is effective for the Company for its fiscal year 2020. While we are still in the process of evaluating the effect of adoption on our consolidated financial statements and are currently assessing our leases, we expect the adoption will lead to a significant increase in the assets and liabilities recorded on our Condensed Consolidated Balance Sheets. In June 2016, the FASB issued its final standard on measurement of credit losses on financial instruments. This standard, issued as ASU 2016-13, requires that an entity measure impairment of certain financial instruments, including trade receivables, based on expected losses rather than incurred losses. This update is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, with early adoption permitted for financial statement periods beginning after December 15, 2018. The new standard is effective for the Company for its fiscal year 2021. The Company is currently evaluating this standard to determine the impact of adoption on its consolidated financial statements. In January 2017, the FASB issued its final standard on simplifying the test for goodwill impairment, ASU 2017-04, Intangibles – Goodwill and Other (Topic 350). This standard will require 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. This update is effective for annual and interim goodwill impairment tests in fiscal years beginning after December 15, 2019, with early adoption permitted. The new standard is effective for the Company for its fiscal year 2021. Upon adoption, the Company will apply this guidance prospectively to its annual and interim goodwill impairment tests and disclose the change in accounting principle. In August 2018, the SEC adopted the final rule under SEC Release No. 33-10532, Disclosure Update and Simplification, amending certain disclosure requirements that were redundant, duplicative, overlapping, outdated or superseded. In addition, the amendments expanded the disclosure requirements on the analysis of stockholders’ equity for interim financial statements. Under the amendments, an analysis of change in each caption of stockholders’ equity presented in the consolidated balance sheet must be provided in a note or separate statement. The analysis should present a reconciliation of the beginning balance to the ending balance of each period for which a statement of comprehensive income is required to be filed. The final rules are effective for all filings made on or after November 5, 2018, with the option for the filer’s first presentation of the changes in shareholders’ equity to be included in its Form 10-Q for the quarter that begins after the effective date of the amendments. The Company anticipates its first presentation of the expanded disclosure requirements of the changes in stockholders’ equity to be in its Form 10-Q for the second quarter of fiscal year 2019. 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 be significant to the Company’s financial position, results of operations or cash flows. Reclassification Certain of the prior period Cash Flows from Financing Activities line items were reclassified into “Other, Net” within our condensed consolidated statements of cash flows to conform to our current period presentation. These reclassifications did not affect the total amount of Cash Flows from Financing Activities.

Note 1. Basis of Presentation

The accompanying condensed consolidated financial statements include MSC Industrial Direct Co., Inc. (“MSC”) and all its subsidiaries (hereinafter referred to collectively as the “Company”). All intercompany balances and transactions have been eliminated in consolidation.

The unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all the information and notes required by accounting principles generally accepted in the United States for complete financial statements. In the opinion of management, all adjustments considered necessary for a fair presentation (including normal recurring adjustments) have been included. Operating results for the thirteen-week period ended December 1, 2018 are not necessarily indicative of the results that may be expected for the fiscal year ending August 31, 2019. For further information, refer to the financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended September 1, 2018.

The Company’s fiscal year ends on the Saturday closest to August 31 of each year. Unless the context requires otherwise, references to years contained herein pertain to the Company’s fiscal year. The Company’s 2019 fiscal year will be a 52-week accounting period that will end on August 31, 2019 and its 2018 fiscal year was a 52-week accounting period that ended on September 1, 2018.

Recently Adopted Accounting Pronouncements

Effective September 2, 2018, the Company adopted the Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers (Topic 606) as modified by subsequently issued ASUs 2015-14, 2016-08, 2016-10, 2016-12, 2016-20 and 2017-05. These ASUs outline a single comprehensive model for entities to use in the accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. Revenue continues to be recognized when products are shipped to the customer and the adoption of these ASUs, using the modified retrospective approach, had no impact to the Company’s opening retained earnings. The Company reports its sales net of estimated sales returns and sales incentives. Sales tax collected from customers is excluded from net sales. Additional information and disclosures required by this new standard are contained in Note 2, Revenue.

Effective September 2, 2018, the Company adopted ASU 2017-01, which clarifies the definition of a business to assist entities with evaluating when a set of transferred assets and activities is considered a business. This standard will be applied to appropriate business combinations that occur beginning September 2, 2018.

Accounting Pronouncements Not Yet Adopted

In February 2016, the FASB issued its final standard on accounting for leases, ASU 2016-02, Leases (Topic 842). This standard requires that an entity that is a lessee recognize lease assets and lease liabilities on the balance sheet for all leases and disclose key information about leasing arrangements. This update is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, with earlier application permitted. The new standard is effective for the Company for its fiscal year 2020. While we are still in the process of evaluating the effect of adoption on our consolidated financial statements and are currently assessing our leases, we expect the adoption will lead to a significant increase in the assets and liabilities recorded on our Condensed Consolidated Balance Sheets.

In June 2016, the FASB issued its final standard on measurement of credit losses on financial instruments. This standard, issued as ASU 2016-13, requires that an entity measure impairment of certain financial instruments, including trade receivables, based on expected losses rather than incurred losses. This update is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, with early adoption permitted for financial statement periods beginning after December 15, 2018. The new standard is effective for the Company for its fiscal year 2021. The Company is currently evaluating this standard to determine the impact of adoption on its consolidated financial statements.

In January 2017, the FASB issued its final standard on simplifying the test for goodwill impairment, ASU 2017-04, Intangibles – Goodwill and Other (Topic 350). This standard will require 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. This update is effective for annual and interim goodwill impairment tests in fiscal years beginning after December 15, 2019, with early adoption permitted. The new standard is effective for the Company for its fiscal year 2021. Upon adoption, the Company will apply this guidance prospectively to its annual and interim goodwill impairment tests and disclose the change in accounting principle.

In August 2018, the SEC adopted the final rule under SEC Release No. 33-10532, Disclosure Update and Simplification, amending certain disclosure requirements that were redundant, duplicative, overlapping, outdated or superseded. In addition, the amendments expanded the disclosure requirements on the analysis of stockholders’ equity for interim financial statements. Under the amendments, an analysis of change in each caption of stockholders’ equity presented in the consolidated balance sheet must be provided in a note or separate statement. The analysis should present a reconciliation of the beginning balance to the ending balance of each period for which a statement of comprehensive income is required to be filed. The final rules are effective for all filings made on or after November 5, 2018, with the option for the filer’s first presentation of the changes in shareholders’ equity to be included in its Form 10-Q for the quarter that begins after the effective date of the amendments. The Company anticipates its first presentation of the expanded disclosure requirements of the changes in stockholders’ equity to be in its Form 10-Q for the second quarter of fiscal year 2019.

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 be significant to the Company’s financial position, results of operations or cash flows.

Reclassification

Certain of the prior period Cash Flows from Financing Activities line items were reclassified into “Other, Net” within our condensed consolidated statements of cash flows to conform to our current period presentation. These reclassifications did not affect the total amount of Cash Flows from Financing Activities.