Business and Basis of Presentation	3 Months Ended
Mar. 31, 2024
Accounting Policies [Abstract]
Business and Basis of Presentation	NOTE 1. BUSINESS AND BASIS OF PRESENTATION Armstrong World Industries, Inc. (“AWI”) is a Pennsylvania corporation incorporated in 1891. When we refer to “AWI,” the “Company,” “we,” “our” or “us” in these notes, we are referring to AWI and its subsidiaries. Except as disclosed in this note, the accounting policies used in preparing the Condensed Consolidated Financial Statements in this Form 10-Q are the same as those used in preparing the Consolidated Financial Statements for the year ended December 31, 2023. These statements should therefore be read in conjunction with the Consolidated Financial Statements and notes that are included in the Annual Report on Form 10-K for the fiscal year ended December 31, 2023. In the opinion of management, all adjustments of a normal recurring nature have been included to provide a fair statement of the results for the reporting periods presented. Operating results for the first quarter of 2024 and 2023 included in this report are unaudited. Quarterly results are not necessarily indicative of annual earnings, primarily due to the different level of sales in each quarter of the year and the possibility of changes in general economic conditions. These Condensed Consolidated Financial Statements are prepared in accordance with U.S. generally accepted accounting principles. The statements include management estimates and judgments, where appropriate. Management utilizes estimates to record many items, including certain asset values, contingent purchase price liabilities, allowances for bad debts, inventory obsolescence and lower of cost and net realizable value charges, warranty reserves, workers’ compensation, general liability and environmental claims, and income taxes. When preparing an estimate, management determines the amount based upon the consideration of relevant information and may confer with outside parties, including external counsel. Actual results may differ from these estimates. Acquisitions and Investments in Unconsolidated Affiliates In January 2024, we entered into a strategic partnership and equity investment in Overcast Innovations LLC (“Overcast”) with McKinstry Essention, LLC whereby we contributed $5.5 million in exchange for a 19.5% ownership interest in Overcast, with future rights to increase our ownership interest. Overcast is a solutions company offering prefabricated ceiling cloud systems, modular grid platforms and engineering design services to reduce waste and inefficiencies in the built environment. Our investment and equity earnings in Overcast are included in our Unallocated Corporate segment. In October 2023, we acquired a portion of the business and certain assets of Insolcorp, LLC (“Insolcorp”), based in Albemarle, NC, used to develop, test and manufacture energy saving products deployed in building and roofing installations. The acquired operations, assets and liabilities of Insolcorp are included in our Mineral Fiber segment. In July 2023, we acquired all of the issued and outstanding stock of BOK Modern, LLC (“BOK”), based in San Rafael, CA. BOK is a designer of metal facade architectural solutions. The operations, assets and liabilities of BOK are included in our Architectural Specialties segment. Subsequent Event In April 2024, we acquired all of the issued and outstanding membership interests in 3form, LLC, a subsidiary of Hunter Douglas, Inc. (“3form”), for a purchase price of $95.0 million. 3form, based in Salt Lake City, UT, is a designer and manufacturer of architectural resin and glass products used for specialty walls, partitions and ceilings, with three U.S. based production and design facilities and 2023 revenues of approximately $96 million.

Business and Basis of Presentation

3 Months Ended

Mar. 31, 2024

NOTE 1. BUSINESS AND BASIS OF PRESENTATION

Armstrong World Industries, Inc. (“AWI”) is a Pennsylvania corporation incorporated in 1891. When we refer to “AWI,” the “Company,” “we,” “our” or “us” in these notes, we are referring to AWI and its subsidiaries.

Except as disclosed in this note, the accounting policies used in preparing the Condensed Consolidated Financial Statements in this Form 10-Q are the same as those used in preparing the Consolidated Financial Statements for the year ended December 31, 2023. These statements should therefore be read in conjunction with the Consolidated Financial Statements and notes that are included in the Annual Report on Form 10-K for the fiscal year ended December 31, 2023. In the opinion of management, all adjustments of a normal recurring nature have been included to provide a fair statement of the results for the reporting periods presented. Operating results for the first quarter of 2024 and 2023 included in this report are unaudited. Quarterly results are not necessarily indicative of annual earnings, primarily due to the different level of sales in each quarter of the year and the possibility of changes in general economic conditions.

These Condensed Consolidated Financial Statements are prepared in accordance with U.S. generally accepted accounting principles. The statements include management estimates and judgments, where appropriate. Management utilizes estimates to record many items, including certain asset values, contingent purchase price liabilities, allowances for bad debts, inventory obsolescence and lower of cost and net realizable value charges, warranty reserves, workers’ compensation, general liability and environmental claims, and income taxes. When preparing an estimate, management determines the amount based upon the consideration of relevant information and may confer with outside parties, including external counsel. Actual results may differ from these estimates.

Acquisitions and Investments in Unconsolidated Affiliates

In January 2024, we entered into a strategic partnership and equity investment in Overcast Innovations LLC (“Overcast”) with McKinstry Essention, LLC whereby we contributed $5.5 million in exchange for a 19.5% ownership interest in Overcast, with future rights to increase our ownership interest. Overcast is a solutions company offering prefabricated ceiling cloud systems, modular grid platforms and engineering design services to reduce waste and inefficiencies in the built environment. Our investment and equity earnings in Overcast are included in our Unallocated Corporate segment.

In October 2023, we acquired a portion of the business and certain assets of Insolcorp, LLC (“Insolcorp”), based in Albemarle, NC, used to develop, test and manufacture energy saving products deployed in building and roofing installations. The acquired operations, assets and liabilities of Insolcorp are included in our Mineral Fiber segment.

In July 2023, we acquired all of the issued and outstanding stock of BOK Modern, LLC (“BOK”), based in San Rafael, CA. BOK is a designer of metal facade architectural solutions. The operations, assets and liabilities of BOK are included in our Architectural Specialties segment.

Subsequent Event

In April 2024, we acquired all of the issued and outstanding membership interests in 3form, LLC, a subsidiary of Hunter Douglas, Inc. (“3form”), for a purchase price of $95.0 million. 3form, based in Salt Lake City, UT, is a designer and manufacturer of architectural resin and glass products used for specialty walls, partitions and ceilings, with three U.S. based production and design facilities and 2023 revenues of approximately $96 million.