Business And Basis Of Presentation	9 Months Ended
Sep. 30, 2013
Business And Basis Of Presentation [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 "we", "our" and "us" in these notes, we are referring to AWI and its subsidiaries. We use the term “AWI” when we are referring solely to Armstrong World Industries, Inc. In December 2000, AWI filed a voluntary petition for relief (the “Filing”) under Chapter 11 of the U.S. Bankruptcy Code (the “Bankruptcy Code”) in the United States Bankruptcy Court for the District of Delaware (the “Bankruptcy Court”) in order to use the court-supervised reorganization process to achieve a resolution of AWI’s asbestos-related liability. On October 2, 2006, AWI’s court-approved plan of reorganization (“POR”) became effective and AWI emerged from Chapter 11. All claims in AWI’s Chapter 11 case have been resolved and closed. On October 2, 2006, the Armstrong World Industries, Inc. Asbestos Personal Injury Settlement Trust (“Asbestos PI Trust”) was created to address AWI’s personal injury (including wrongful death) asbestos-related liability. All present and future asbestos-related personal injury claims against AWI, including contribution claims of co-defendants but excluding certain foreign claims against subsidiaries, arising directly or indirectly out of AWI’s pre-Filing use of, or other activities involving, asbestos are channeled to the Asbestos PI Trust. In August 2009, Armor TPG Holdings LP (“TPG”) and the Asbestos PI Trust entered into agreements whereby TPG purchased 7,000,000 shares of AWI common stock from the Asbestos PI Trust and acquired an economic interest in an additional 1,039,777 shares from the Asbestos PI Trust. During the fourth quarter of 2012, the Asbestos PI Trust and TPG together sold 5,980,000 of their shares in a secondary public offering. Additionally, during the third quarter of 2013, the Asbestos PI Trust and TPG together sold 12,057,382 of their remaining shares in a secondary public offering. During this transaction we paid approximately $260 million to acquire 5,057,382 shares to be held in treasury. The treasury share purchase was funded by existing cash and borrowings under our credit and securitization facilities. As a result of these transactions the Asbestos PI Trust and TPG together now hold approximately 35% of AWI’s outstanding shares and maintain a shareholders’ agreement, pursuant to which they agree to vote their shares together on certain matters. We did not sell any shares and did not receive any proceeds from these offerings. In September 2012, we entered into a definitive agreement to sell our cabinets business for $27 million. The sale was completed in October 2012. The transaction was subject to working capital adjustments which were completed in the second quarter of 2013. The financial results of the cabinets business, which were previously shown as a separate reporting segment, have been reclassified as discontinued operations for all periods presented. See Note 3 to the Condensed Consolidated Financial Statements for additional financial information related to discontinued operations. 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, 2012. These statements should therefore be read in conjunction with the Consolidated Financial Statements and notes that are included in the Form 10-K for the fiscal year ended December 31, 2012. 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. 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. Certain amounts in the prior year’s Condensed Consolidated Financial Statements have been recast to conform to the 2013 presentation. 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, allowances for bad debts, inventory obsolescence and lower of cost or market charges, warranty, 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. Management may confer with outside parties, including outside counsel. Actual results may differ from these estimates. In July 2013, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2013-11 “Income Taxes - Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists” which is part of Accounting Standards Codification (“ASC”) 740: Income Taxes. The new guidance requires an entity to present an unrecognized tax benefit and a net operating loss (“NOL”) carryforward, a similar tax loss, or a tax credit carryforward on a net basis as part of a deferred tax asset, unless the unrecognized tax benefit is not available to reduce the deferred tax asset component or would not be utilized for that purpose, then a liability would be recognized. The guidance is to be applied prospectively and will be effective for us beginning January 1, 2014. Since this guidance impacts presentation only, it will have no effect on our financial condition, results of operations or cash flows. In February 2013, the FASB issued new guidance that is now part of ASC 220: “Comprehensive Income – Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income”. The new guidance requires an entity to disclose in a single location the effects of reclassifications out of accumulated other comprehensive income “(“AOCI”). For items reclassified out of AOCI and into net income in their entirety, entities must disclose the effect of the reclassification on each affected net income item. For AOCI reclassification items that are not reclassified in their entirety into net income, entities must provide a cross reference to other required U.S. GAAP disclosures. The standard does not change the items which must be reported in other comprehensive income. These provisions are to be applied prospectively and were effective for us January 1, 2013. There was no impact on our financial condition, results of operations or cash flows as a result of the adoption of this guidance. The FASB also issued new guidance that limits the scope of instruments subject to ASU 2011-11: “Balance Sheet – Disclosures about Offsetting Assets and Liabilities” originally issued in December 2011. The 2011 guidance required an entity to provide additional disclosures to allow investors to better compare financial statements prepared under U.S. GAAP with financial statements prepared under International Financial Reporting Standards. The 2013 guidance limits the scope of the 2011 guidance requirements to derivatives, repurchase and reverse repurchase agreements, and securities borrowing and lending agreements subject to master netting arrangements or similar agreements. This guidance is to be applied retrospectively and was effective for us beginning January 1, 2013. Since this guidance impacts presentation only, it had no effect on our financial condition, results of operations or cash flows. Operating results for the third quarter and first nine months of 2013 and 2012 included in this report are unaudited. However, these Condensed Consolidated Financial Statements have been reviewed by an independent registered public accounting firm in accordance with standards of the Public Company Accounting Oversight Board (United States) for a limited review of interim financial information.

NOTE 1. BUSINESS AND BASIS OF PRESENTATION

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

In December 2000, AWI filed a voluntary petition for relief (the “Filing”) under Chapter 11 of the U.S. Bankruptcy Code (the “Bankruptcy Code”) in the United States Bankruptcy Court for the District of Delaware (the “Bankruptcy Court”) in order to use the court-supervised reorganization process to achieve a resolution of AWI’s asbestos-related liability. On October 2, 2006, AWI’s court-approved plan of reorganization (“POR”) became effective and AWI emerged from Chapter 11. All claims in AWI’s Chapter 11 case have been resolved and closed.

On October 2, 2006, the Armstrong World Industries, Inc. Asbestos Personal Injury Settlement Trust (“Asbestos PI Trust”) was created to address AWI’s personal injury (including wrongful death) asbestos-related liability. All present and future asbestos-related personal injury claims against AWI, including contribution claims of co-defendants but excluding certain foreign claims against subsidiaries, arising directly or indirectly out of AWI’s pre-Filing use of, or other activities involving, asbestos are channeled to the Asbestos PI Trust.

In August 2009, Armor TPG Holdings LP (“TPG”) and the Asbestos PI Trust entered into agreements whereby TPG purchased 7,000,000 shares of AWI common stock from the Asbestos PI Trust and acquired an economic interest in an additional 1,039,777 shares from the Asbestos PI Trust. During the fourth quarter of 2012, the Asbestos PI Trust and TPG together sold 5,980,000 of their shares in a secondary public offering. Additionally, during the third quarter of 2013, the Asbestos PI Trust and TPG together sold 12,057,382 of their remaining shares in a secondary public offering. During this transaction we paid approximately $260 million to acquire 5,057,382 shares to be held in treasury. The treasury share purchase was funded by existing cash and borrowings under our credit and securitization facilities. As a result of these transactions the Asbestos PI Trust and TPG together now hold approximately 35% of AWI’s outstanding shares and maintain a shareholders’ agreement, pursuant to which they agree to vote their shares together on certain matters. We did not sell any shares and did not receive any proceeds from these offerings.

In September 2012, we entered into a definitive agreement to sell our cabinets business for $27 million. The sale was completed in October 2012. The transaction was subject to working capital adjustments which were completed in the second quarter of 2013. The financial results of the cabinets business, which were previously shown as a separate reporting segment, have been reclassified as discontinued operations for all periods presented. See Note 3 to the Condensed Consolidated Financial Statements for additional financial information related to discontinued operations.

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, 2012. These statements should therefore be read in conjunction with the Consolidated Financial Statements and notes that are included in the Form 10-K for the fiscal year ended December 31, 2012. 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. 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.

Certain amounts in the prior year’s Condensed Consolidated Financial Statements have been recast to conform to the 2013 presentation.

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, allowances for bad debts, inventory obsolescence and lower of cost or market charges, warranty, 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. Management may confer with outside parties, including outside counsel. Actual results may differ from these estimates.

In July 2013, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2013-11 “Income Taxes - Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists” which is part of Accounting Standards Codification (“ASC”) 740: Income Taxes. The new guidance requires an entity to present an unrecognized tax benefit and a net operating loss (“NOL”) carryforward, a similar tax loss, or a tax credit carryforward on a net basis as part of a deferred tax asset, unless the unrecognized tax benefit is not available to reduce the deferred tax asset component or would not be utilized for that purpose, then a liability would be recognized. The guidance is to be applied prospectively and will be effective for us beginning January 1, 2014. Since this guidance impacts presentation only, it will have no effect on our financial condition, results of operations or cash flows.

In February 2013, the FASB issued new guidance that is now part of ASC 220: “Comprehensive Income – Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income”. The new guidance requires an entity to disclose in a single location the effects of reclassifications out of accumulated other comprehensive income “(“AOCI”). For items reclassified out of AOCI and into net income in their entirety, entities must disclose the effect of the reclassification on each affected net income item. For AOCI reclassification items that are not reclassified in their entirety into net income, entities must provide a cross reference to other required U.S. GAAP disclosures. The standard does not change the items which must be reported in other comprehensive income. These provisions are to be applied prospectively and were effective for us January 1, 2013. There was no impact on our financial condition, results of operations or cash flows as a result of the adoption of this guidance.

The FASB also issued new guidance that limits the scope of instruments subject to ASU 2011-11: “Balance Sheet – Disclosures about Offsetting Assets and Liabilities” originally issued in December 2011. The 2011 guidance required an entity to provide additional disclosures to allow investors to better compare financial statements prepared under U.S. GAAP with financial statements prepared under International Financial Reporting Standards. The 2013 guidance limits the scope of the 2011 guidance requirements to derivatives, repurchase and reverse repurchase agreements, and securities borrowing and lending agreements subject to master netting arrangements or similar agreements. This guidance is to be applied retrospectively and was effective for us beginning January 1, 2013. Since this guidance impacts presentation only, it had no effect on our financial condition, results of operations or cash flows.

Operating results for the third quarter and first nine months of 2013 and 2012 included in this report are unaudited. However, these Condensed Consolidated Financial Statements have been reviewed by an independent registered public accounting firm in accordance with standards of the Public Company Accounting Oversight Board (United States) for a limited review of interim financial information.