Business and Basis of Presentation	9 Months Ended
Sep. 30, 2020
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, 2019. These statements should therefore be read in conjunction with the Consolidated Financial Statements and notes that are included in the Amendment No. 1 to the Annual Report on Form 10-K/A for the fiscal year ended December 31, 2019. 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 third quarter and first nine months of 2020 and 2019 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 (“U.S. GAAP”). 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. Certain prior year amounts have been reclassified in the Condensed Consolidated Financial Statements to conform to the 2020 presentation. Acquisitions In August 2020, we acquired the business and assets of Moz Designs, Inc. (“Moz”), based in Oakland, California. Moz is a designer and fabricator of custom architectural metal ceilings, walls, dividers and column covers for interior and exterior applications with one manufacturing facility. Moz’s operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment. In July 2020, we acquired all the issued and outstanding capital stock of TURF Design Inc. (“Turf”), with one manufacturing facility in Elgin, Illinois and a design center in Chicago, Illinois. Turf is a designer and manufacturer of acoustic felt ceilings and wall products. Turf’s operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment. 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. See Note 4 for further information on our recent acquisitions. Discontinued Operations On September 30, 2019, we completed the 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 2018 and was subject to certain post-closing adjustments for cash and debt as provided in the 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. During the three and nine months ended September 30, 2020, we remitted $5.9 and $25.9 million, respectively, to WAVE for their portion of the proceeds from Knauf. During the nine months ended September 30, 2020, WAVE paid each of AWI and Worthington dividends of $13.0 million relating to these payments. During the third quarter of 2020, we remitted $6.4 million to Knauf for working capital and other adjustments. Final adjustments are subject to negotiations with Knauf related to the valuation of certain liabilities included in the Sale, which we expect to be finalized in 2020. The final valuation could result in an increase to those liabilities of $11.0 million; however, we have not accrued a liability for this matter as of September 30, 2020 as payment is not probable. In 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 provided certain transition technology, finance and information technology support services, which are now substantially complete. In connection with the closing of the Sale, we also entered into (i) a royalty-free intellectual property License Agreement with Knauf under which they license patents, trademarks and know-how from us for use in licensed territories in which the business was conducted prior to the Sale, 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 term of the granted licenses, with respect to each intellectual property right, extend until the expiration or abandonment of each such intellectual property right. The EMEA and Pacific Rim segment historical financial results for the three and nine months ended September 30, 2019 have been reflected in AWI’s Condensed Consolidated Statements of Operations and Comprehensive Income as discontinued operations, while the assets and liabilities of discontinued operations were removed from AWI’s Condensed Consolidated Balance Sheet as of September 30, 2019. Recently Adopted Accounting Standards In June 2016, the FASB issued ASU 2016-13, "Measurement of Credit Losses on Financial Instruments," which requires immediate recognition of estimated credit losses that are expected to occur over the remaining life of many financial assets. This standard applies to all financial assets, including trade receivables. Our current accounts receivable policy uses historical and current information to estimate the amount of probable credit losses in our existing accounts receivable balances. Effective January 1, 2020, we adopted this standard, which had no material impact on our financial condition, results of operations or cash flows. In January 2017, the FASB issued ASU 2017-04, “Intangibles – Goodwill and Other,” which simplifies the subsequent measurement of goodwill by eliminating the second step from the current goodwill impairment test. Under this standard, an entity recognizes an impairment charge for the amount by which the carrying value of the reporting unit goodwill exceeds the fair value. Effective January 1, 2020, we adopted this standard prospectively. Our adoption of this standard had no impact on our financial condition or results of operations. In August 2018, the FASB issued ASU 2018-13, “Changes to the Disclosure Requirements for Fair Value Measurement.” This standard eliminates the current requirement to disclose the amount or reason for transfers between level 1 and level 2 of the fair value hierarchy and the requirement to disclose the valuation methodology for level 3 fair value measurements. The standard includes additional disclosure requirements for level 3 fair value measurements, including the requirement to disclose the changes in unrealized gains and losses in other comprehensive income during the period and permits the disclosure of other relevant quantitative information for certain unobservable inputs. Effective January 1, 2020, we adopted this standard, which resulted in additional disclosures for level 3 fair value measurements. In August 2018, the FASB issued ASU 2018-15, “Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That is a Service Contract,” which amends ASC 350-40 Intangibles – Goodwill and Other – Internal-Use Software. The ASU requires implementation costs incurred by customers in cloud computing arrangements to be deferred and recognized over the term of the arrangement, if these costs were capitalized by the customer in a software licensing arrangement. Effective January 1, 2020, we adopted this standard prospectively. Our adoption of this standard had no material impact on our financial condition, results of operations or cash flows. In March 2020, the FASB issued ASU 2020-04, “Facilitation of the Effects of Reference Rate Reform on Financial Reporting,” which provides optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships and other transactions affected by the discontinuation of the London Interbank Offered Rate (LIBOR) and other interbank offered rates. This guidance is effective through December 31, 2022. Effective the second quarter of 2020 we adopted this standard, which had no impact on our financial condition, results of operations and cash flows. Recently Issued Accounting Standards In August 2018, the FASB issued ASU 2018-14, “Disclosure Framework – Changes to the Disclosure Requirements for Defined Benefit Plans,” which amends ASC 715-20, Compensation – Retirement Benefits – Defined Benefit Plans. The ASU modifies the disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans. The disclosure requirements to be removed include the amounts in accumulated other comprehensive income expected to be recognized in net periodic benefit costs over the next fiscal year, the amount and timing of plan assets expected to be returned to the employer and the effect of a one percentage point change in assumed health care cost trend rates on the aggregate service cost and benefit obligation for postretirement health care benefits. The new disclosure requirements include the interest crediting rates for cash balance plans, and an explanation of significant gains and losses related to changes in benefit obligations. This guidance is effective for fiscal years ending after December 15, 2020. We are evaluating the impact the adoption of this standard will have on our disclosures. In December 2019, the FASB issued ASU 2019-12, “Simplifying the Accounting for Income Taxes,” which removes exceptions to the general principles in ASC Topic 740 – Income Taxes for allocating tax expense between financial statement components, accounting basis differences resulting from an ownership change in foreign investments and interim period income tax accounting for year-to-date losses that exceed projected losses. This guidance is effective for fiscal years beginning after December 15, 2020. We are evaluating the impact the adoption of this standard will have on our financial condition and results of operations. COVID-19 Considerations The COVID-19 outbreak has created significant volatility and economic disruption and the impact on our future consolidated results of operations is uncertain. The extent to which COVID-19 impacts our employees, operations, customers, suppliers and financial results depends on numerous evolving factors that we are not be able to accurately predict, including: the duration and scope of the pandemic; government actions taken in response to the pandemic; the impact on construction activity; the effect on our customers demand for our ceiling and wall systems; our ability to manufacture and sell our products; and the ability of our customers to pay for our products. While many of our products support life sustaining activities and essential construction, we, and certain of our customers or suppliers, may be impacted by state actions, orders and policies regarding the COVID-19 pandemic, including temporary closures of non-life sustaining businesses, shelter-in-place orders, and travel, social distancing and quarantine policies, the implementation and enforcement of which vary by individual U.S. states and by individual countries in the Americas. We did not record any asset impairments, inventory charges or bad debt reserves related to COVID-19 during the third quarter and first nine months of 2020 but future events may require such charges, which could have a material adverse effect on our financial condition, liquidity or results of operations.

Business and Basis of Presentation

9 Months Ended

Sep. 30, 2020

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, 2019. These statements should therefore be read in conjunction with the Consolidated Financial Statements and notes that are included in the Amendment No. 1 to the Annual Report on Form 10-K/A for the fiscal year ended December 31, 2019. 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 third quarter and first nine months of 2020 and 2019 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 (“U.S. GAAP”). 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.

Certain prior year amounts have been reclassified in the Condensed Consolidated Financial Statements to conform to the 2020 presentation.

Acquisitions

In August 2020, we acquired the business and assets of Moz Designs, Inc. (“Moz”), based in Oakland, California. Moz is a designer and fabricator of custom architectural metal ceilings, walls, dividers and column covers for interior and exterior applications with one manufacturing facility. Moz’s operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment.

In July 2020, we acquired all the issued and outstanding capital stock of TURF Design Inc. (“Turf”), with one manufacturing facility in Elgin, Illinois and a design center in Chicago, Illinois. Turf is a designer and manufacturer of acoustic felt ceilings and wall products. Turf’s operations, and its assets and liabilities, are included as a component of our Architectural Specialties segment.

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.

See Note 4 for further information on our recent acquisitions.

Discontinued Operations

On September 30, 2019, we completed the 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 2018 and was subject to certain post-closing adjustments for cash and debt as provided in the 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. During the three and nine months ended September 30, 2020, we remitted $5.9 and $25.9 million, respectively, to WAVE for their portion of the proceeds from Knauf. During the nine months ended September 30, 2020, WAVE paid each of AWI and Worthington dividends of $13.0

million relating to these payments. During the third quarter of 2020, we remitted $6.4 million to Knauf for working capital and other adjustments. Final adjustments are subject to negotiations with Knauf related to the valuation of certain liabilities included in the Sale, which we expect to be finalized in 2020. The final valuation could result in an increase to those liabilities of $11.0 million; however, we have not accrued a liability for this matter as of September 30, 2020 as payment is not probable.

In 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 provided certain transition technology, finance and information technology support services, which are now substantially complete. In connection with the closing of the Sale, we also entered into (i) a royalty-free intellectual property License Agreement with Knauf under which they license patents, trademarks and know-how from us for use in licensed territories in which the business was conducted prior to the Sale, 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 term of the granted licenses, with respect to each intellectual property right, extend until the expiration or abandonment of each such intellectual property right.

The EMEA and Pacific Rim segment historical financial results for the three and nine months ended September 30, 2019 have been reflected in AWI’s Condensed Consolidated Statements of Operations and Comprehensive Income as discontinued operations, while the assets and liabilities of discontinued operations were removed from AWI’s Condensed Consolidated Balance Sheet as of September 30, 2019.

Recently Adopted Accounting Standards

In June 2016, the FASB issued ASU 2016-13, "Measurement of Credit Losses on Financial Instruments," which requires immediate recognition of estimated credit losses that are expected to occur over the remaining life of many financial assets. This standard applies to all financial assets, including trade receivables. Our current accounts receivable policy uses historical and current information to estimate the amount of probable credit losses in our existing accounts receivable balances. Effective January 1, 2020, we adopted this standard, which had no material impact on our financial condition, results of operations or cash flows.

In January 2017, the FASB issued ASU 2017-04, “Intangibles – Goodwill and Other,” which simplifies the subsequent measurement of goodwill by eliminating the second step from the current goodwill impairment test. Under this standard, an entity recognizes an impairment charge for the amount by which the carrying value of the reporting unit goodwill exceeds the fair value. Effective January 1, 2020, we adopted this standard prospectively. Our adoption of this standard had no impact on our financial condition or results of operations.

In August 2018, the FASB issued ASU 2018-13, “Changes to the Disclosure Requirements for Fair Value Measurement.” This standard eliminates the current requirement to disclose the amount or reason for transfers between level 1 and level 2 of the fair value hierarchy and the requirement to disclose the valuation methodology for level 3 fair value measurements. The standard includes additional disclosure requirements for level 3 fair value measurements, including the requirement to disclose the changes in unrealized gains and losses in other comprehensive income during the period and permits the disclosure of other relevant quantitative information for certain unobservable inputs. Effective January 1, 2020, we adopted this standard, which resulted in additional disclosures for level 3 fair value measurements.

In August 2018, the FASB issued ASU 2018-15, “Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That is a Service Contract,” which amends ASC 350-40 Intangibles – Goodwill and Other – Internal-Use Software. The ASU requires implementation costs incurred by customers in cloud computing arrangements to be deferred and recognized over the term of the arrangement, if these costs were capitalized by the customer in a software licensing arrangement. Effective January 1, 2020, we adopted this standard prospectively. Our adoption of this standard had no material impact on our financial condition, results of operations or cash flows.

In March 2020, the FASB issued ASU 2020-04, “Facilitation of the Effects of Reference Rate Reform on Financial Reporting,” which provides optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships and other transactions affected by the discontinuation of the London Interbank Offered Rate (LIBOR) and other interbank offered rates. This guidance is effective through December 31, 2022. Effective the second quarter of 2020 we adopted this standard, which had no impact on our financial condition, results of operations and cash flows.

Recently Issued Accounting Standards

In August 2018, the FASB issued ASU 2018-14, “Disclosure Framework – Changes to the Disclosure Requirements for Defined Benefit Plans,” which amends ASC 715-20, Compensation – Retirement Benefits – Defined Benefit Plans. The ASU modifies the

disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans. The disclosure requirements to be removed include the amounts in accumulated other comprehensive income expected to be recognized in net periodic benefit costs over the next fiscal year, the amount and timing of plan assets expected to be returned to the employer and the effect of a one percentage point change in assumed health care cost trend rates on the aggregate service cost and benefit obligation for postretirement health care benefits. The new disclosure requirements include the interest crediting rates for cash balance plans, and an explanation of significant gains and losses related to changes in benefit obligations. This guidance is effective for fiscal years ending after December 15, 2020. We are evaluating the impact the adoption of this standard will have on our disclosures.

In December 2019, the FASB issued ASU 2019-12, “Simplifying the Accounting for Income Taxes,” which removes exceptions to the general principles in ASC Topic 740 – Income Taxes for allocating tax expense between financial statement components, accounting basis differences resulting from an ownership change in foreign investments and interim period income tax accounting for year-to-date losses that exceed projected losses. This guidance is effective for fiscal years beginning after December 15, 2020. We are evaluating the impact the adoption of this standard will have on our financial condition and results of operations.

COVID-19 Considerations

The COVID-19 outbreak has created significant volatility and economic disruption and the impact on our future consolidated results of operations is uncertain. The extent to which COVID-19 impacts our employees, operations, customers, suppliers and financial results depends on numerous evolving factors that we are not be able to accurately predict, including: the duration and scope of the pandemic; government actions taken in response to the pandemic; the impact on construction activity; the effect on our customers demand for our ceiling and wall systems; our ability to manufacture and sell our products; and the ability of our customers to pay for our products. While many of our products support life sustaining activities and essential construction, we, and certain of our customers or suppliers, may be impacted by state actions, orders and policies regarding the COVID-19 pandemic, including temporary closures of non-life sustaining businesses, shelter-in-place orders, and travel, social distancing and quarantine policies, the implementation and enforcement of which vary by individual U.S. states and by individual countries in the Americas. We did not record any asset impairments, inventory charges or bad debt reserves related to COVID-19 during the third quarter and first nine months of 2020 but future events may require such charges, which could have a material adverse effect on our financial condition, liquidity or results of operations.