Company Overview	3 Months Ended
Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Company Overview	1. Company Overview Beacon Roofing Supply, Inc. (“Beacon” or the “Company”) was incorporated in the state of Delaware on August 22, 1997 and is the largest publicly traded distributor of residential and non-residential roofing materials and complementary building products in the United States and Canada. On December 20, 2020, the Company entered into an Equity Purchase Agreement (the “Purchase Agreement”) with ASP Sailor Acquisition Corp. (the “Buyer”). Pursuant to the Purchase Agreement, Beacon has agreed to sell its interior products and insulation businesses (“Interior Products”) to the Buyer, an entity controlled by affiliates of American Securities LLC. Subject to the terms and conditions of the Purchase Agreement, the Buyer has agreed to purchase all of the outstanding equity interests in a limited liability company newly formed to hold Interior Products for a purchase price of $850 million in cash payable at closing, subject to certain customary adjustments set forth in the Purchase Agreement. The definitive agreement was publicly announced on December 21, 2020. The transaction is expected to close during the Company’s fiscal 2021 second quarter, subject to customary closing conditions as set forth in the Purchase Agreement. The Company has reflected Interior Products as discontinued operations for all periods presented. For additional information, see Notes 2 and 3. On January 15, 2020, the Company announced the rebranding of its exterior products branches with the trade name “Beacon Building Products” (the “Rebranding”). The new name, and a related logo, were adopted at over 450 Beacon one-step exterior products branches. The Company’s Interior Products, weatherproofing and two-step branches continue to operate under legacy brand names. The Company operates its business under regional and local trade names and services customers in all 50 states throughout the U.S. and 6 provinces in Canada. The Company’s material subsidiaries are Beacon Sales Acquisition, Inc. and Beacon Roofing Supply Canada Company.

Company Overview

3 Months Ended

Dec. 31, 2020

Organization Consolidation And Presentation Of Financial Statements [Abstract]

1. Company Overview

Beacon Roofing Supply, Inc. (“Beacon” or the “Company”) was incorporated in the state of Delaware on August 22, 1997 and is the largest publicly traded distributor of residential and non-residential roofing materials and complementary building products in the United States and Canada.

On December 20, 2020, the Company entered into an Equity Purchase Agreement (the “Purchase Agreement”) with ASP Sailor Acquisition Corp. (the “Buyer”). Pursuant to the Purchase Agreement, Beacon has agreed to sell its interior products and insulation businesses (“Interior Products”) to the Buyer, an entity controlled by affiliates of American Securities LLC. Subject to the terms and conditions of the Purchase Agreement, the Buyer has agreed to purchase all of the outstanding equity interests in a limited liability company newly formed to hold Interior Products for a purchase price of $850 million in cash payable at closing, subject to certain customary adjustments set forth in the Purchase Agreement. The definitive agreement was publicly announced on December 21, 2020. The transaction is expected to close during the Company’s fiscal 2021 second quarter, subject to customary closing conditions as set forth in the Purchase Agreement. The Company has reflected Interior Products as discontinued operations for all periods presented. For additional information, see Notes 2 and 3.

On January 15, 2020, the Company announced the rebranding of its exterior products branches with the trade name “Beacon Building Products” (the “Rebranding”). The new name, and a related logo, were adopted at over 450 Beacon one-step exterior products branches. The Company’s Interior Products, weatherproofing and two-step branches continue to operate under legacy brand names.

The Company operates its business under regional and local trade names and services customers in all 50 states throughout the U.S. and 6 provinces in Canada. The Company’s material subsidiaries are Beacon Sales Acquisition, Inc. and Beacon Roofing Supply Canada Company.