Summary Of Significant Accounting Policies (Policy)	12 Months Ended
Dec. 31, 2012
Summary Of Significant Accounting Policies [Abstract]
Consolidation Policy	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	Use of Estimates. We prepare our financial statements in conformity with U.S. generally accepted accounting principles, which requires management to make estimates and assumptions. These estimates and assumptions affect the reported amounts of assets, liabilities, revenues and expenses. 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.
Reclassifications	Reclassifications. Certain amounts in the prior year’s Consolidated Financial Statements and related notes thereto have been recast to conform to the 2012 presentation. The December 31, 2011 consolidated statement of cash flows has been revised to reflect a reclassification of $12.5 million from operating activities to investing activities ($8.9 million) and to financing activities ($3.6 million). The December 31, 2010 consolidated statement of cash flows has been revised to reflect a reclassification of $1.4 million from operating activities to investing activities. The revisions are related to the correction of the classification of premium payments on company-owned life insurance policies, proceeds received on those policies and loans under those policies. This revision did not affect the consolidated statement of earnings and comprehensive income for the years ended December 31, 2011 or 2010.
Revenue Recognition	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. Sales incentives are reflected as a reduction of net sales.
Shipping And Handling Cost	Shipping and Handling Costs. Shipping and handling costs are reflected in cost of goods sold.
Advertising Costs	Advertising Costs. We recognize advertising expenses as they are incurred.
Research And Development Costs	Research and Development Costs. We recognize research and development costs as they are incurred.
Pension And Postretirement Benefits	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 19 to the Consolidated Financial Statements for disclosures on pension and postretirement benefits.
Taxes	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 reduce the carrying amounts of deferred tax assets by a valuation allowance if, based on the available evidence, it is more likely than not that such assets will not be realized. The need to establish valuation allowances for deferred tax assets is assessed quarterly. In assessing the requirement for, and amount of, a valuation allowance in accordance with the more likely than not standard, we give appropriate consideration to all positive and negative evidence related to the realization of the deferred tax assets. This assessment considers, among other matters, the nature, frequency and severity of current and cumulative losses, forecasts of future profitability and foreign source income, the duration of statutory carryforward periods, and our experience with operating loss and tax credit carryforward expirations. A history of cumulative losses is a significant piece of negative evidence used in our assessment. If a history of cumulative losses is incurred for a tax jurisdiction, forecasts of future profitability are not used as positive evidence related to the realization of the deferred tax assets in the assessment. We recognize the tax benefits of an uncertain tax position if those benefits are more likely than not to be sustained based on existing tax law. Additionally, we establish a reserve for tax positions that are more likely than not to be sustained based on existing tax law, but uncertain in the ultimate benefit to be sustained upon examination by the relevant taxing authorities. Unrecognized tax benefits are subsequently recognized at the time the more likely than not recognition threshold is met, the tax matter is effectively settled or the statute of limitations for the relevant taxing authority to examine and challenge the tax position has expired, whichever is earlier. Taxes collected from customers and remitted to governmental authorities are reported on a net basis.
Earnings Per Common Share	Earnings per Common Share. Basic earnings per share is computed by dividing the earnings from continuing operations attributable to common shares 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. 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	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 2012, 2011, and 2010. We monitor the creditworthiness of our customers and generally do not require collateral.
Receivables	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. 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. Inventories are valued at the lower of cost or market. Inventories also include certain samples used in ongoing sales and marketing activities. See Note 8 to the Consolidated Financial Statements for further information on our accounting for inventories.
Property And Depreciation	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	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	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. 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 derived from 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 12 to the Consolidated Financial Statements for disclosure on intangible assets.
Foreign Currency Transactions	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	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 20 and 21 to the Consolidated Financial Statements for further discussion.
Share-Based Employee Compensation	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 25 to the Consolidated Financial Statements for additional information on share-based employee compensation.
Subsequent Events	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.

Summary Of Significant Accounting Policies (Policy)

12 Months Ended

Dec. 31, 2012

Summary Of Significant Accounting Policies [Abstract]

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

Use of Estimates. We prepare our financial statements in conformity with U.S. generally accepted accounting principles, which requires management to make estimates and assumptions. These estimates and assumptions affect the reported amounts of assets, liabilities, revenues and expenses. 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.

Reclassifications

Reclassifications. Certain amounts in the prior year’s Consolidated Financial Statements and related notes thereto have been recast to conform to the 2012 presentation.

The December 31, 2011 consolidated statement of cash flows has been revised to reflect a reclassification of $12.5 million from operating activities to investing activities ($8.9 million) and to financing activities ($3.6 million). The December 31, 2010 consolidated statement of cash flows has been revised to reflect a reclassification of $1.4 million from operating activities to investing activities. The revisions are related to the correction of the classification of premium payments on company-owned life insurance policies, proceeds received on those policies and loans under those policies. This revision did not affect the consolidated statement of earnings and comprehensive income for the years ended December 31, 2011 or 2010.

Revenue Recognition

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

Shipping And Handling Cost

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

Advertising Costs

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

Research And Development Costs

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

Pension And Postretirement Benefits

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 19 to the Consolidated Financial Statements for disclosures on pension and postretirement benefits.

Taxes

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 reduce the carrying amounts of deferred tax assets by a valuation allowance if, based on the available evidence, it is more likely than not that such assets will not be realized. The need to establish valuation allowances for deferred tax assets is assessed quarterly. In assessing the requirement for, and amount of, a valuation allowance in accordance with the more likely than not standard, we give appropriate consideration to all positive and negative evidence related to the realization of the deferred tax assets. This assessment considers, among other matters, the nature, frequency and severity of current and cumulative losses, forecasts of future profitability and foreign source income, the duration of statutory carryforward periods, and our experience with operating loss and tax credit carryforward expirations. A history of cumulative losses is a significant piece of negative evidence used in our assessment. If a history of cumulative losses is incurred for a tax jurisdiction, forecasts of future profitability are not used as positive evidence related to the realization of the deferred tax assets in the assessment.

We recognize the tax benefits of an uncertain tax position if those benefits are more likely than not to be sustained based on existing tax law. Additionally, we establish a reserve for tax positions that are more likely than not to be sustained based on existing tax law, but uncertain in the ultimate benefit to be sustained upon examination by the relevant taxing authorities. Unrecognized tax benefits are subsequently recognized at the time the more likely than not recognition threshold is met, the tax matter is effectively settled or the statute of limitations for the relevant taxing authority to examine and challenge the tax position has expired, whichever is earlier.

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

Earnings Per Common Share

Earnings per Common Share. Basic earnings per share is computed by dividing the earnings from continuing operations attributable to common shares 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. 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

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 2012, 2011, and 2010. We monitor the creditworthiness of our customers and generally do not require collateral.

Receivables

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.

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. Inventories are valued at the lower of cost or market. Inventories also include certain samples used in ongoing sales and marketing activities. See Note 8 to the Consolidated Financial Statements for further information on our accounting for inventories.

Property And Depreciation

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

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

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. 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 derived from 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 12 to the Consolidated Financial Statements for disclosure on intangible assets.

Foreign Currency Transactions

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

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 20 and 21 to the Consolidated Financial Statements for further discussion.

Share-Based Employee Compensation

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 25 to the Consolidated Financial Statements for additional information on share-based employee compensation.

Subsequent Events

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.