Summary Of Significant Accounting Policies	12 Months Ended
Dec. 31, 2011
Summary Of Significant Accounting Policies [Abstract]
Summary Of Significant Accounting Policies	NOTE 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Consolidation Policy. The consolidated financial statements and accompanying data in this report include the accounts of AWI and its majority-owned subsidiaries. All significant intercompany transactions have been eliminated from the consolidated financial statements. Use of Estimates. These 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 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. Revenue Recognition. We recognize revenue from the sale of products when persuasive evidence of an arrangement exists, title and risk of loss transfers to the customers, prices are fixed and determinable, and it is reasonably assured the related accounts receivable is collectible. Our sales terms primarily are FOB shipping point. We have some sales terms that are FOB destination. Our products are sold with normal and customary return provisions. Sales discounts are deducted immediately from the sales invoice. Provisions, which are recorded as a reduction of revenue, are made for the estimated cost of rebates, promotional programs and warranties. We defer recognizing revenue if special sales agreements, established at the time of sale, warrant this treatment. Sales Incentives. Sales incentives are reflected as a reduction of net sales. Shipping and Handling Costs. Shipping and handling costs are reflected in cost of goods sold. Advertising Costs. We recognize advertising expenses as they are incurred. Research and Development Costs. We recognize research and development costs as they are incurred. Pension and Postretirement Benefits. We have benefit plans that provide for pension, medical and life insurance benefits to certain eligible employees when they retire from active service. See Note 18 to the Consolidated Financial Statements for disclosures on pension and postretirement benefits. Taxes. The provision for income taxes has been determined using the asset and liability approach of accounting for income taxes to reflect the expected future tax consequences of events recognized in the financial statements. Deferred income tax assets and liabilities are recognized by applying enacted tax rates to temporary differences that exist as of the balance sheet date which result from differences in the timing of reported taxable income between tax and financial reporting. We record valuation allowances to reduce our deferred income tax assets if it is more likely than not that some portion or all of the deferred income tax assets will not be realized. For tax benefits that may be challenged by a taxing authority, we make an assessment of whether the position is more likely than not to be sustained upon an examination by the taxing authorities. Based on this analysis, we record the impact of these uncertain tax positions, including penalties and interest in the period in which such determination is made. Taxes collected from customers and remitted to governmental authorities are reported on a net basis. Earnings per Common Share. Basic earnings per share is computed by dividing the earnings by the weighted average number of shares of common stock outstanding during the period. Diluted earnings per common share reflects the potential dilution of securities that could share in the earnings. Cash and Cash Equivalents. Cash and cash equivalents include cash on hand and short-term investments that have maturities of three months or less when purchased. Concentration of Credit. We principally sell products to customers in the building products industries in various geographic regions. No one customer accounted for 10% or more of our total consolidated net sales in the years 2011, 2010, and 2009. We monitor the creditworthiness of our customers and generally do not require collateral. Receivables. We sell the vast majority of our products to select, pre-approved customers using customary trade terms that allow for payment in the future. Customer trade receivables, customer notes receivable and miscellaneous receivables (which include supply related rebates and claims to be received, unpaid insurance claims from litigation and other), net of allowances for doubtful accounts, customer credits and warranties are reported in accounts and notes receivable, net. Notes receivable from divesting certain businesses are included in other current assets and other non-current assets based upon the payment terms. Cash flows from the collection of current receivables are classified as operating cash flows on the consolidated statements of cash flows. Cash flows from the collection of non-current receivables are classified as investing cash flows on the consolidated statements of cash flows. We establish credit-worthiness prior to extending credit. We estimate the recoverability of receivables each period. This estimate is based upon triggering events and new information in the period, which can include the review of any available financial statements and forecasts, as well as discussions with legal counsel and the management of the debtor company. As events occur, which impact the collectability of the receivable, all or a portion of the receivable is reserved. Account balances are charged off against the allowance when the potential for recovery is considered remote. We do not have any off-balance-sheet credit exposure related to our customers. Inventories. Inventories are valued at the lower of cost or market. Inventories also include certain samples used in ongoing sales and marketing activities. See Note 7 to the Consolidated Financial Statements for further information on our accounting for inventories. Property and Depreciation. Depreciation charges for financial reporting purposes are determined on a straight-line basis at rates calculated to provide for the full depreciation of assets at the end of their useful lives. Machinery and equipment includes manufacturing equipment (depreciated over 3 to 15 years), computer equipment (3 to 5 years) and office furniture and equipment (5 to 7 years). Within manufacturing equipment, assets that are subject to quick obsolescence or wear out quickly, such as tooling and engraving equipment, are depreciated over shorter periods (3 to 7 years). Heavy production equipment, such as conveyors and production presses, are depreciated over longer periods (15 years). Buildings are depreciated over 15 to 30 years, depending on factors such as type of construction and use. Computer software is depreciated over 3 to 7 years. Property, plant and equipment are tested for impairment when indicators of impairment are present, such as operating losses and/or negative cash flows. If an indication of impairment exists, we compare the carrying amount of the asset group to the estimated undiscounted future cash flows expected to be generated by the assets. The estimate of an asset group's fair value is based on discounted future cash flows expected to be generated by the asset group, or based on management's estimated exit price assuming the assets could be sold in an orderly transaction between market participants, or estimated salvage value if no sale is assumed. If the fair value is less than the carrying value of the asset group, we record an impairment charge equal to the difference between the fair value and carrying value of the asset group. Impairments of assets related to our manufacturing operations are recorded in cost of goods sold. When assets are disposed of or retired, their costs and related depreciation are removed from the financial statements, and any resulting gains or losses normally are reflected in cost of goods sold or selling, general and administrative ("SG&A") expenses. Asset Retirement Obligations. We recognize the fair value of obligations associated with the retirement of tangible long-lived assets in the period in which they are incurred. Upon initial recognition of a liability, the discounted cost is capitalized as part of the related long-lived asset and depreciated over the corresponding asset's useful life. Over time, accretion of the liability is recognized as an operating expense to reflect the change in the liability's present value. Intangible Assets. We periodically review significant definite-lived intangible assets for impairment when indicators of impairment exist. We review our businesses for indicators of impairment such as operating losses and/or negative cash flows. If an indication of impairment exists, we compare the carrying amount of the asset group to the estimated undiscounted future cash flows expected to be generated by the assets. The estimate of an asset group's fair value is based on discounted future cash flows expected to be generated by the asset group, or based on management's estimated exit price assuming the assets could be sold in an orderly transaction between market participants. If the fair value is less than the carrying value of the asset group, we record an impairment charge equal to the difference between the fair value and carrying value of the asset group. Our indefinite-lived intangibles are primarily trademarks and brand names, which are integral to our corporate identity and expected to contribute indefinitely to our cash flows. Accordingly, they have been assigned an indefinite life. We perform annual impairment tests during the fourth quarter on these indefinite-lived intangibles. These assets undergo more frequent tests if an indication of possible impairment exists. The principal assumptions utilized in our impairment tests for definite-lived intangible assets include operating profit adjusted for depreciation and amortization and discount rate. The principal assumptions utilized in our impairment tests for indefinite-lived intangible assets include revenue growth rate, discount rate and royalty rate. Revenue growth rate and operating profit assumptions are consistent with those utilized in our operating plan and strategic planning processes. The discount rate assumption is calculated based upon an estimated weighted average cost of equity which reflects the overall level of inherent risk and the rate of return a market participant would expect to achieve. Methodologies used for valuing our intangible assets did not change from prior periods. See Note 11 to the Consolidated Financial Statements for disclosure on intangible assets. Foreign Currency Transactions. Assets and liabilities of our subsidiaries operating outside the United States which account in a functional currency other than U.S. dollars are translated using the period end exchange rate. Revenues and expenses are translated at exchange rates effective during each month. Foreign currency translation gains or losses are included as a component of accumulated other comprehensive (loss) within shareholders' equity. Gains or losses on foreign currency transactions are recognized through the statement of earnings. Financial Instruments and Derivatives. From time to time, we use derivatives and other financial instruments to offset the effect of currency, interest rate and commodity price variability. See Notes 19 and 20 to the Consolidated Financial Statements for further discussion. Share-based Employee Compensation. For awards with only service and performance conditions that have a graded vesting schedule, we recognize compensation expense on a straight-line basis over the vesting period for the entire award. For awards with market conditions, we recognize compensation expense over the derived service period. See Note 24 to the Consolidated Financial Statements for additional information on share-based employee compensation. Subsequent Events. We have evaluated subsequent events for potential recognition and disclosure through the date the consolidated financial statements included in the Annual Report on Form 10-K were issued. Recently Adopted Accounting Standards During 2010, we adopted guidance which is now part of Accounting Standards Codification ("ASC") 820, "Fair Value Measurements and Disclosures". The guidance requires disclosures of the amounts of assets and liabilities transferred into and out of Levels 1 and 2, along with a description of the reasons for the transfers. The new guidance also requires additional disclosures related to activity presented for Level 3 measurements. These provisions were effective for us as of January 1, 2010 except for the additional disclosures related to activities for Level 3 measurements which were effective for us as of January 1, 2011. There was no impact on our financial statements from the adoption of this guidance. During 2010, we adopted guidance which is now part of ASC 815, "Derivatives and Hedging". The guidance clarifies the scope exception for embedded credit related derivatives. The provisions were effective for us as of January 1, 2011. There was no impact on our financial statements from the adoption of this guidance. During 2010, we adopted guidance which is now part of ASC 310, "Receivables". The guidance increases the disclosure requirements regarding the credit quality of financing receivables and the allowance for credit losses. Some of the provisions were effective for us as of December 31, 2010 and others were effective January 1, 2011. There was no impact on our financial statements from the adoption of this guidance. In September 2011, the Financial Accounting Standards Board ("FASB") issued new guidance that is now part of ASC 350: "Intangibles – Goodwill and Other". The new guidance permits an entity to first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount as a basis for determining whether it is necessary to perform the two-step goodwill impairment test. Because the objective of this new guidance is to simplify how entities test for goodwill impairment, it did not have a material impact on our financial statements. Recently Issued Accounting Standards In June 2011, the FASB issued new guidance that is now part of ASC 220: "Presentation of Comprehensive Income". The new guidance will require companies to present the components of net income and other comprehensive income either as one continuous statement or as two consecutive statements. It eliminates the option to present components of other comprehensive income as part of the statement of changes in stockholder's equity. The standard does not change the items which must be reported in other comprehensive income. In November 2011, the FASB decided to defer the effective date of those changes that relate to the presentation of reclassification adjustments, but this does not impact the effective date of the other requirements in this guidance. These provisions are to be applied retrospectively and will be effective for us as of January 1, 2012. Because this guidance impacts presentation only, it will have no effect on our financial condition, results of operations or cash flows. In December 2011, the FASB issued Accounting Standards Update ("ASU") 2011-11: "Balance Sheet –Disclosures about Offsetting Assets and Liabilities" in conjunction with the International Accounting Standards Board's issuance of amendments to International Financial Reporting Standard ("IFRS") 7: "Disclosures – Offsetting Financial Assets and Financial Liabilities". The new standard requires disclosures to allow investors to better compare financial statements prepared under U.S. GAAP with financial statements prepared under IFRS. The guidance is to be applied retrospectively and will be effective for us beginning January 1, 2013. Since this guidance impacts presentation only, it will have no effect on our financial condition, results of operations or cash flows.

NOTE 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Consolidation Policy. The consolidated financial statements and accompanying data in this report include the accounts of AWI and its majority-owned subsidiaries. All significant intercompany transactions have been eliminated from the consolidated financial statements.

Use of Estimates. These 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 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.

Revenue Recognition. We recognize revenue from the sale of products when persuasive evidence of an arrangement exists, title and risk of loss transfers to the customers, prices are fixed and determinable, and it is reasonably assured the related accounts receivable is collectible. Our sales terms primarily are FOB shipping point. We have some sales terms that are FOB destination. Our products are sold with normal and customary return provisions. Sales discounts are deducted immediately from the sales invoice. Provisions, which are recorded as a reduction of revenue, are made for the estimated cost of rebates, promotional programs and warranties. We defer recognizing revenue if special sales agreements, established at the time of sale, warrant this treatment.

Sales Incentives. Sales incentives are reflected as a reduction of net sales.

Shipping and Handling Costs. Shipping and handling costs are reflected in cost of goods sold.

Advertising Costs. We recognize advertising expenses as they are incurred.

Research and Development Costs. We recognize research and development costs as they are incurred.

Pension and Postretirement Benefits. We have benefit plans that provide for pension, medical and life insurance benefits to certain eligible employees when they retire from active service. See Note 18 to the Consolidated Financial Statements for disclosures on pension and postretirement benefits.

Taxes. The provision for income taxes has been determined using the asset and liability approach of accounting for income taxes to reflect the expected future tax consequences of events recognized in the financial statements. Deferred income tax assets and liabilities are recognized by applying enacted tax rates to temporary differences that exist as of the balance sheet date which result from differences in the timing of reported taxable income between tax and financial reporting.

We record valuation allowances to reduce our deferred income tax assets if it is more likely than not that some portion or all of the deferred income tax assets will not be realized. For tax benefits that may be challenged by a taxing authority, we make an assessment of whether the position is more likely than not to be sustained upon an examination by the taxing authorities. Based on this analysis, we record the impact of these uncertain tax positions, including penalties and interest in the period in which such determination is made.

Taxes collected from customers and remitted to governmental authorities are reported on a net basis.

Earnings per Common Share. Basic earnings per share is computed by dividing the earnings by the weighted average number of shares of common stock outstanding during the period. Diluted earnings per common share reflects the potential dilution of securities that could share in the earnings.

Cash and Cash Equivalents. Cash and cash equivalents include cash on hand and short-term investments that have maturities of three months or less when purchased.

Concentration of Credit. We principally sell products to customers in the building products industries in various geographic regions. No one customer accounted for 10% or more of our total consolidated net sales in the years 2011, 2010, and 2009. We monitor the creditworthiness of our customers and generally do not require collateral.

Receivables. We sell the vast majority of our products to select, pre-approved customers using customary trade terms that allow for payment in the future. Customer trade receivables, customer notes receivable and miscellaneous receivables (which include supply related rebates and claims to be received, unpaid insurance claims from litigation and other), net of allowances for doubtful accounts, customer credits and warranties are reported in accounts and notes receivable, net. Notes receivable from divesting certain businesses are included in other current assets and other non-current assets based upon the payment terms. Cash flows from the collection of current receivables are classified as operating cash flows on the consolidated statements of cash flows. Cash flows from the collection of non-current receivables are classified as investing cash flows on the consolidated statements of cash flows.

We establish credit-worthiness prior to extending credit. We estimate the recoverability of receivables each period. This estimate is based upon triggering events and new information in the period, which can include the review of any available financial statements and forecasts, as well as discussions with legal counsel and the management of the debtor company. As events occur, which impact the collectability of the receivable, all or a portion of the receivable is reserved. Account balances are charged off against the allowance when the potential for recovery is considered remote. We do not have any off-balance-sheet credit exposure related to our customers.

Inventories. Inventories are valued at the lower of cost or market. Inventories also include certain samples used in ongoing sales and marketing activities. See Note 7 to the Consolidated Financial Statements for further information on our accounting for inventories.

Property and Depreciation. Depreciation charges for financial reporting purposes are determined on a straight-line basis at rates calculated to provide for the full depreciation of assets at the end of their useful lives. Machinery and equipment includes manufacturing equipment (depreciated over 3 to 15 years), computer equipment (3 to 5 years) and office furniture and equipment (5 to 7 years). Within manufacturing equipment, assets that are subject to quick obsolescence or wear out quickly, such as tooling and engraving equipment, are depreciated over shorter periods (3 to 7 years). Heavy production equipment, such as conveyors and production presses, are depreciated over longer periods (15 years). Buildings are depreciated over 15 to 30 years, depending on factors such as type of construction and use. Computer software is depreciated over 3 to 7 years.

Property, plant and equipment are tested for impairment when indicators of impairment are present, such as operating losses and/or negative cash flows. If an indication of impairment exists, we compare the carrying amount of the asset group to the estimated undiscounted future cash flows expected to be generated by the assets. The estimate of an asset group's fair value is based on discounted future cash flows expected to be generated by the asset group, or based on management's estimated exit price assuming the assets could be sold in an orderly transaction between market participants, or estimated salvage value if no sale is assumed. If the fair value is less than the carrying value of the asset group, we record an impairment charge equal to the difference between the fair value and carrying value of the asset group. Impairments of assets related to our manufacturing operations are recorded in cost of goods sold. When assets are disposed of or retired, their costs and related depreciation are removed from the financial statements, and any resulting gains or losses normally are reflected in cost of goods sold or selling, general and administrative ("SG&A") expenses.

Asset Retirement Obligations. We recognize the fair value of obligations associated with the retirement of tangible long-lived assets in the period in which they are incurred. Upon initial recognition of a liability, the discounted cost is capitalized as part of the related long-lived asset and depreciated over the corresponding asset's useful life. Over time, accretion of the liability is recognized as an operating expense to reflect the change in the liability's present value.

Intangible Assets. We periodically review significant definite-lived intangible assets for impairment when indicators of impairment exist. We review our businesses for indicators of impairment such as operating losses and/or negative cash flows. If an indication of impairment exists, we compare the carrying amount of the asset group to the estimated undiscounted future cash flows expected to be generated by the assets. The estimate of an asset group's fair value is based on discounted future cash flows expected to be generated by the asset group, or based on management's estimated exit price assuming the assets could be sold in an orderly transaction between market participants. If the fair value is less than the carrying value of the asset group, we record an impairment charge equal to the difference between the fair value and carrying value of the asset group.

Our indefinite-lived intangibles are primarily trademarks and brand names, which are integral to our corporate identity and expected to contribute indefinitely to our cash flows. Accordingly, they have been assigned an indefinite life. We perform annual impairment tests during the fourth quarter on these indefinite-lived intangibles. These assets undergo more frequent tests if an indication of possible impairment exists.

The principal assumptions utilized in our impairment tests for definite-lived intangible assets include operating profit adjusted for depreciation and amortization and discount rate. The principal assumptions utilized in our impairment tests for indefinite-lived intangible assets include revenue growth rate, discount rate and royalty rate. Revenue growth rate and operating profit assumptions are consistent with those utilized in our operating plan and strategic planning processes. The discount rate assumption is calculated based upon an estimated weighted average cost of equity which reflects the overall level of inherent risk and the rate of return a market participant would expect to achieve. Methodologies used for valuing our intangible assets did not change from prior periods.

See Note 11 to the Consolidated Financial Statements for disclosure on intangible assets.

Foreign Currency Transactions. Assets and liabilities of our subsidiaries operating outside the United States which account in a functional currency other than U.S. dollars are translated using the period end exchange rate. Revenues and expenses are translated at exchange rates effective during each month. Foreign currency translation gains or losses are included as a component of accumulated other comprehensive (loss) within shareholders' equity. Gains or losses on foreign currency transactions are recognized through the statement of earnings.

Financial Instruments and Derivatives. From time to time, we use derivatives and other financial instruments to offset the effect of currency, interest rate and commodity price variability. See Notes 19 and 20 to the Consolidated Financial Statements for further discussion.

Share-based Employee Compensation. For awards with only service and performance conditions that have a graded vesting schedule, we recognize compensation expense on a straight-line basis over the vesting period for the entire award. For awards with market conditions, we recognize compensation expense over the derived service period. See Note 24 to the Consolidated Financial Statements for additional information on share-based employee compensation.

Subsequent Events. We have evaluated subsequent events for potential recognition and disclosure through the date the consolidated financial statements included in the Annual Report on Form 10-K were issued.

Recently Adopted Accounting Standards

During 2010, we adopted guidance which is now part of Accounting Standards Codification ("ASC") 820, "Fair Value Measurements and Disclosures". The guidance requires disclosures of the amounts of assets and liabilities transferred into and out of Levels 1 and 2, along with a description of the reasons for the transfers. The new guidance also requires additional disclosures related to activity presented for Level 3 measurements. These provisions were effective for us as of January 1, 2010 except for the additional disclosures related to activities for Level 3 measurements which were effective for us as of January 1, 2011. There was no impact on our financial statements from the adoption of this guidance.

During 2010, we adopted guidance which is now part of ASC 815, "Derivatives and Hedging". The guidance clarifies the scope exception for embedded credit related derivatives. The provisions were effective for us as of January 1, 2011. There was no impact on our financial statements from the adoption of this guidance.

During 2010, we adopted guidance which is now part of ASC 310, "Receivables". The guidance increases the disclosure requirements regarding the credit quality of financing receivables and the allowance for credit losses. Some of the provisions were effective for us as of December 31, 2010 and others were effective January 1, 2011. There was no impact on our financial statements from the adoption of this guidance.

In September 2011, the Financial Accounting Standards Board ("FASB") issued new guidance that is now part of ASC 350: "Intangibles – Goodwill and Other". The new guidance permits an entity to first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount as a basis for determining whether it is necessary to perform the two-step goodwill impairment test. Because the objective of this new guidance is to simplify how entities test for goodwill impairment, it did not have a material impact on our financial statements.

Recently Issued Accounting Standards

In June 2011, the FASB issued new guidance that is now part of ASC 220: "Presentation of Comprehensive Income". The new guidance will require companies to present the components of net income and other comprehensive income either as one continuous statement or as two consecutive statements. It eliminates the option to present components of other comprehensive income as part of the statement of changes in stockholder's equity. The standard does not change the items which must be reported in other comprehensive income. In November 2011, the FASB decided to defer the effective

date of those changes that relate to the presentation of reclassification adjustments, but this does not impact the effective date of the other requirements in this guidance. These provisions are to be applied retrospectively and will be effective for us as of January 1, 2012. Because this guidance impacts presentation only, it will have no effect on our financial condition, results of operations or cash flows.

In December 2011, the FASB issued Accounting Standards Update ("ASU") 2011-11: "Balance Sheet –Disclosures about Offsetting Assets and Liabilities" in conjunction with the International Accounting Standards Board's issuance of amendments to International Financial Reporting Standard ("IFRS") 7: "Disclosures – Offsetting Financial Assets and Financial Liabilities". The new standard requires disclosures to allow investors to better compare financial statements prepared under U.S. GAAP with financial statements prepared under IFRS. The guidance is to be applied retrospectively and will be effective for us beginning January 1, 2013. Since this guidance impacts presentation only, it will have no effect on our financial condition, results of operations or cash flows.