Business	12 Months Ended
Dec. 31, 2019
Business [Abstract]
Business	NOTE 1. BUSINESS Armstrong World Industries, Inc. (“AWI”) is a Pennsylvania corporation incorporated in 1891. When we refer to “AWI,” the “Company,” “we,” “our” and “us” in these notes, we are referring to AWI and its subsidiaries. Acquisitions In November 2019, we acquired the business and assets of MRK Industries, Inc. (“MRK”), based in Libertyville, Illinois. MRK is a manufacturer of specialty metal ceiling, wall and exterior solutions with one manufacturing facility. MRK’s operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment. In March 2019, we acquired the business and assets of Architectural Components Group, Inc. (“ACGI”), based in Marshfield, Missouri. ACGI is a manufacturer of custom wood ceilings and walls with one manufacturing facility. ACGI’s operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment. In August 2018, we acquired the business and assets of Steel Ceilings, Inc. (“Steel Ceilings”), based in Johnstown, Ohio. Steel Ceilings is a manufacturer of aluminum and stainless metal ceilings that include architectural, radiant and security solutions with one manufacturing facility. Steel Ceilings’ operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment. In May 2018, we acquired the business and assets of Plasterform, Inc. (“Plasterform”), based in Mississauga, Ontario, Canada. Plasterform is a manufacturer of architectural cast ceilings, walls, facades, columns and moldings with one manufacturing facility. Plasterform’s operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment. In January 2017, we acquired the business and assets of Tectum, Inc. (“Tectum”), based in Newark, Ohio. Tectum is a manufacturer of acoustical ceiling, wall and structural solutions for commercial building applications with two manufacturing facilities. Tectum’s operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment. See Note 6 for further information on our recent acquisitions. Discontinued Operations On September 30, 2019, we completed the previously announced sale of certain subsidiaries comprising our businesses and operations in Europe, the Middle East and Africa (including Russia) (“EMEA”) and the Pacific Rim, including the corresponding businesses and operations conducted by Worthington Armstrong Venture (“WAVE”), our joint venture with Worthington Industries, Inc. (“Worthington”) in which AWI holds a 50% interest (collectively, the “Sale”), to Knauf International GmbH (“Knauf”). The purchase price of $330.0 million was previously paid by Knauf to us during the third quarter of 2018 and is subject to certain post-closing adjustments for cash and debt as provided in the Share Purchase Agreement dated as of November 17, 2017, by and between us and Knauf (the “Purchase Agreement”), including adjustments based on the economic impact of any required regulatory remedies and a working capital adjustment. On July 18, 2018, we entered into an amendment to the Purchase Agreement, pursuant to which Knauf irrevocably and unconditionally paid AWI (i) $250.0 million of the purchase price on August 1, 2018, and (ii) $80.0 million of the purchase price on September 15, 2018, which payments were credited against the aggregate consideration payable at closing. The amendment also provided for the reduction (from a maximum of $35.0 million to a maximum of $20.0 million) of potential adjustments to the purchase price consideration for the transaction based on the impact of remedies required to satisfy competition conditions. Following receipt of these payments, we remitted $70.0 million to WAVE in partial consideration of the purchase price payable in respect of the businesses and operations of WAVE under the transaction. WAVE subsequently paid each of AWI and Worthington a dividend of $35.0 million. We have recorded a $25.9 million payable to WAVE for their remaining portion of the proceeds from Knauf, which is reflected within Accounts payable and accrued expenses in the Consolidated Balance Sheets as of December 31, 2019. The transaction and final gain or loss amounts are subject to finalization of customary working capital and other adjustments, as provided in the Purchase Agreement. For the year ended December 31, 2019, payments to Knauf included $61.0 million of adjustments to cash consideration, estimated working capital adjustments and remedies, offset by $13.1 million of additional cash in international WAVE entities. On December 7, 2018, the European Commission granted conditional clearance of the transaction, subject to certain commitments intended to address concerns regarding the overlap between the activities of AWI and Knauf, including the divestment by Knauf to a third party of certain mineral fiber and grid businesses and operations in Austria, Estonia, Germany, Ireland, Italy, Latvia, Lithuania, Portugal, Spain, Turkey and the United Kingdom (“UK”). This included our sales operations in each of the relevant countries, as well as our production facilities, and those of WAVE, located in Team Valley, UK. On May 23, 2019, we entered into a Transition Services Agreement with Knauf for its benefit and the benefit of the buyer of the divestment business, pursuant to which we are providing certain transition technology, finance and information technology support services during the period between March 18, 2019 and September 30, 2020. On September 23, 2019, the European Commission approved the Sale, as well as the terms of the sale of the divestment business by Knauf and the identity of the purchaser. In connection with the closing of the Sale, we also entered into (i) an intellectual property License Agreement with Knauf for its benefit (and, under sublicense, to the buyer of the divestment business) under which they license certain patents, trademarks and know-how from us for use in certain licensed territories, and (ii) a Supply Agreement with Knauf under which the parties may continue to purchase certain products from each other following the closing of the Sale. WAVE also entered into similar agreements with Knauf for such purposes. The EMEA and Pacific Rim segment historical financial results through September 30, 2019 have been reflected in AWI’s Consolidated Statements of Earnings and Comprehensive Income as discontinued operations for all periods presented, while the assets and liabilities of discontinued operations have been removed from AWI’s Consolidated Balance Sheet as of December 31, 2019.

Business

12 Months Ended

Dec. 31, 2019

NOTE 1. BUSINESS

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

Acquisitions

In November 2019, we acquired the business and assets of MRK Industries, Inc. (“MRK”), based in Libertyville, Illinois. MRK is a manufacturer of specialty metal ceiling, wall and exterior solutions with one manufacturing facility. MRK’s operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment.

In March 2019, we acquired the business and assets of Architectural Components Group, Inc. (“ACGI”), based in Marshfield, Missouri. ACGI is a manufacturer of custom wood ceilings and walls with one manufacturing facility. ACGI’s operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment.

In August 2018, we acquired the business and assets of Steel Ceilings, Inc. (“Steel Ceilings”), based in Johnstown, Ohio. Steel Ceilings is a manufacturer of aluminum and stainless metal ceilings that include architectural, radiant and security solutions with one manufacturing facility. Steel Ceilings’ operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment.

In May 2018, we acquired the business and assets of Plasterform, Inc. (“Plasterform”), based in Mississauga, Ontario, Canada. Plasterform is a manufacturer of architectural cast ceilings, walls, facades, columns and moldings with one manufacturing facility. Plasterform’s operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment.

In January 2017, we acquired the business and assets of Tectum, Inc. (“Tectum”), based in Newark, Ohio. Tectum is a manufacturer of acoustical ceiling, wall and structural solutions for commercial building applications with two manufacturing facilities. Tectum’s operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment.

See Note 6 for further information on our recent acquisitions.

Discontinued Operations

On September 30, 2019, we completed the previously announced sale of certain subsidiaries comprising our businesses and operations in Europe, the Middle East and Africa (including Russia) (“EMEA”) and the Pacific Rim, including the corresponding businesses and operations conducted by Worthington Armstrong Venture (“WAVE”), our joint venture with Worthington Industries, Inc. (“Worthington”) in which AWI holds a 50% interest (collectively, the “Sale”), to Knauf International GmbH (“Knauf”). The purchase price of $330.0 million was previously paid by Knauf to us during the third quarter of 2018 and is subject to certain post-closing adjustments for cash and debt as provided in the Share Purchase Agreement dated as of November 17, 2017, by and between us and Knauf (the “Purchase Agreement”), including adjustments based on the economic impact of any required regulatory remedies and a working capital adjustment.

On July 18, 2018, we entered into an amendment to the Purchase Agreement, pursuant to which Knauf irrevocably and unconditionally paid AWI (i) $250.0 million of the purchase price on August 1, 2018, and (ii) $80.0 million of the purchase price on September 15, 2018, which payments were credited against the aggregate consideration payable at closing. The amendment also provided for the reduction (from a maximum of $35.0 million to a maximum of $20.0 million) of potential adjustments to the purchase price consideration for the transaction based on the impact of remedies required to satisfy competition conditions. Following receipt of these payments, we remitted $70.0 million to WAVE in partial consideration of the purchase price payable in respect of the businesses and operations of WAVE under the transaction. WAVE subsequently paid each of AWI and Worthington a dividend of $35.0 million. We have recorded a $25.9 million payable to WAVE for their remaining portion of the proceeds from Knauf, which is reflected within Accounts payable and accrued expenses in the Consolidated Balance Sheets as of December 31, 2019. The transaction and final gain or loss amounts are subject to finalization of customary working capital and other adjustments, as provided in the Purchase Agreement. For the year ended December 31, 2019, payments to Knauf included $61.0 million of adjustments to cash consideration, estimated working capital adjustments and remedies, offset by $13.1 million of additional cash in international WAVE entities.

On December 7, 2018, the European Commission granted conditional clearance of the transaction, subject to certain commitments intended to address concerns regarding the overlap between the activities of AWI and Knauf, including the divestment by Knauf to a third party of certain mineral fiber and grid businesses and operations in Austria, Estonia, Germany, Ireland, Italy, Latvia, Lithuania, Portugal, Spain, Turkey and the United Kingdom (“UK”). This included our sales operations in each of the relevant countries, as well as our production facilities, and those of WAVE, located in Team Valley, UK.

On May 23, 2019, we entered into a Transition Services Agreement with Knauf for its benefit and the benefit of the buyer of the divestment business, pursuant to which we are providing certain transition technology, finance and information technology support services during the period between March 18, 2019 and September 30, 2020.

On September 23, 2019, the European Commission approved the Sale, as well as the terms of the sale of the divestment business by Knauf and the identity of the purchaser.

In connection with the closing of the Sale, we also entered into (i) an intellectual property License Agreement with Knauf for its benefit (and, under sublicense, to the buyer of the divestment business) under which they license certain patents, trademarks and know-how from us for use in certain licensed territories, and (ii) a Supply Agreement with Knauf under which the parties may continue to purchase certain products from each other following the closing of the Sale. WAVE also entered into similar agreements with Knauf for such purposes.

The EMEA and Pacific Rim segment historical financial results through September 30, 2019 have been reflected in AWI’s Consolidated Statements of Earnings and Comprehensive Income as discontinued operations for all periods presented, while the assets and liabilities of discontinued operations have been removed from AWI’s Consolidated Balance Sheet as of December 31, 2019.