Business and Basis of Presentation (Policies)	9 Months Ended
Business and Basis of Presentation (Policies)	Sep. 30, 2018
Accounting Policies [Abstract]
Recently Adopted and Recently Issued Accounting Standards	Recently Adopted Accounting Standards In May 2014, the Financial Accounting Standard Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, “Revenue from Contracts with Customers.” The guidance requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to a customer. The ASU replaces most existing revenue recognition guidance in U.S. GAAP. In March 2016, the FASB issued ASU 2016-08, “Principal versus Agent Considerations (Reporting Gross versus Net),” which clarifies the implementation guidance relating to principle versus agent considerations. In April 2016, the FASB issued ASU 2016-10, “Identifying Performance Obligations and Licensing,” which clarifies the implementation guidance relating to the identification of performance obligations in a contract, including how entities should account for shipping and handling services it provides after control of goods transfers to a customer. In May 2016, the FASB issued ASU 2016-12, “Narrow-Scope Improvements and Practical Expedients,” which clarifies the guidance related to the presentation of sales taxes, noncash consideration, and completed contracts and contract modifications. In December 2016, the FASB issued ASU 2016-20, “Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers,” which clarifies the scope and application of the adoption of the new revenue recognition standard. Effective January 1, 2018, we adopted these standards using the modified retrospective transition method and have applied all practical expedients related to completed contracts upon adoption. Substantially all of our revenues from contracts with customers are recognized from the sale of products with standard shipping terms, sales discounts and warranties. This adoption did not have a material impact to our financial condition, results of operations or cash flows as the amount and timing of substantially all of our revenues will continue to be recognized at a point in time. As required by the revenue recognition Accounting Standards Codification (“ASC”) updates, we have expanded our disclosure of revenues from contracts with customers. See Note 3 for additional information. In January 2016, the FASB issued ASU 2016-01, “Recognition and Measurement of Financial Assets and Financial Liabilities,” which addresses certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. This new guidance requires equity investments (except those accounted for under the equity method of accounting or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income. Effective January 1, 2018, our adoption of this standard had no material impact on our financial condition, results of operations or cash flows. In August 2016, the FASB issued ASU 2016-15, “Classification of Certain Cash Receipts and Cash Payments.” This guidance clarifies how entities should classify certain cash receipts and cash payments on the statement of cash flows. Effective January 1, 2018, our adoption of this guidance had no material impact on our cash flows. In March 2017, the FASB issued ASU 2017-07, “Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost,” which requires companies to report the service cost component of net benefit cost in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period. The other components of net benefit cost are required to be presented in the income statement separately from the service cost component and outside a subtotal of income from operations, if one is presented. Effective January 1, 2018, we have adopted this guidance for all periods presented. Upon adoption of this standard we reclassified all non-service cost components of net benefit costs for our defined benefit pension and health and welfare plans. For the three months ended September 30, 2017, this reclassification resulted in a decrease of $7.2 million in cost of goods sold and $5.6 million in Selling General and Administrative (“SG&A”) expenses, offset by a decrease of $12.8 million in other non-operating income, net on the Condensed Consolidated Statement of Earnings. For the first nine months of 2017, this reclassification resulted in an increase of $3.0 million in cost of goods sold, offset by an increase of $3.0 million in other non-operating income, net on the Condensed Consolidated Statement of Earnings. See Note 12 for details related to our components of net benefit costs. In February 2018, the FASB issued ASU 2018-02, “Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.” On December 22, 2017, the U.S. federal government enacted the Tax Cuts and Jobs Act of 2017 (the “2017 Tax Act”), which, in addition to numerous other provisions, lowered the Corporate statutory tax rate from 35% to 21%. Under U.S. GAAP, all deferred tax assets and liabilities are required to be adjusted for the effect of a change in tax laws or rates, with the effect included in income from continuing operations in the reporting period that includes the enactment date. This standard allows entities to record a reclassification from Accumulated Other Comprehensive Income (“AOCI”) to retained earnings for the purpose of appropriately including the tax effect of items within AOCI at the newly enacted 21% U.S. federal tax rate. This new guidance is effective for annual periods beginning after December 15, 2018. Effective January 1, 2018 we early adopted the guidance and recorded a $54.3 million reduction to AOCI with a corresponding increase to retained earnings. Recently Issued Accounting Standards In February 2016, the FASB issued ASU 2016-02, “Leases,” which amends accounting for leases, most notably by requiring a lessee to recognize the assets and liabilities that arise from a lease agreement. Specifically, this new guidance will require lessees to recognize a liability to make lease payments and a right-of-use asset representing its right to use the underlying asset for the lease term, with limited exceptions. The accounting applied by a lessor is largely unchanged from that applied under existing U.S. GAAP. In January 2018, FASB issued ASU 2018-01, “Land Easement Practical Expedient for Transition to Topic 842” which permits an entity to elect an optional transition practical expedient to not evaluate under Topic 842 land easements that exist or expired before the adoption of Topic 842 and that were not previously accounted for as leases under Topic 840. In July 2018, FASB issued ASU 2018-10, “Codification improvements to Topic 842, Leases” which affect narrow aspects of the guidance issued in the amendments in Update 2016-02. In July 2018, FASB also issued ASU 2018-11, “Targeted Improvements” which relates to transition relief on comparative reporting at adoption. Collectively, the guidance and all related ASU updates are effective for annual reporting periods beginning after December 15, 2018. We will adopt ASU 2016-02 effective January 1, 2019 utilizing the modified retrospective approach. Currently we are implementing processes and system tools to assist in the collection and analysis of data related to our lease portfolio. We are also evaluating our accounting policies and internal controls that would be impacted by the new guidance. In August 2017, the FASB issued ASU 2017-12, “Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities,” which amends the financial reporting of hedging relationships in order to better portray the economic results of an entity’s risk management activities in its financial statements. In addition, the guidance simplifies the application of current hedge accounting guidance. This guidance is effective for annual periods beginning after December 15, 2018. We are currently evaluating the impact the adoption of this standard will have on our financial condition, results of operations and cash flows. 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 currently evaluating the impact the adoption of this standard will have on our results of operations. 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. This guidance is effective for fiscal years beginning after December 15, 2019. We are currently evaluating the impact the adoption of this standard will have on our results of operations.
Revenue Recognition	Revenue Recognition We recognize revenue upon transfer of control of our products to the customer, which typically occurs upon shipment. Our main performance obligation to our customers is the delivery of products in accordance with purchase orders. Each purchase order defines the transaction price for the products purchased under the arrangement. Direct sales to building materials distributors, home centers, direct customers, and retailers represent the majority of our sales. Our standard sales terms are Free On Board (“FOB”) shipping point. We have some sales terms that are FOB destination. At the point of shipment, the customer is required to pay under normal sales terms. Our normal payment terms in most cases are 45 days or less and our sales arrangements do not have any material financing components. In addition, our customer arrangements do not produce contract assets or liabilities that are material to our consolidated financial statements. Within our Architectural Specialties segment, the majority of revenues are project driven, which includes a minority of revenues derived from the sale of customer specified customized products that have no alternative use to us. The manufacturing cycle for these custom products is short. Incremental costs to fulfill our customer arrangements are expensed as incurred, as the amortization period is less than one year. Our products are sold with normal and customary return provisions. We provide limited warranties for defects in materials or factory workmanship, sagging and warping, and certain other manufacturing defects. Warranties are not sold separately to customers. Our product warranties place certain requirements on the purchaser, including installation and maintenance in accordance with our written instructions. In addition to our warranty program, under certain limited circumstances, we will occasionally and at our sole discretion, provide a customer accommodation repair or replacement. Warranty repairs and replacements are most commonly made by professional installers employed by or affiliated with our independent distributors. Reimbursement for costs associated with warranty repairs are provided to our independent distributors through a credit against accounts receivable from the distributor to us. Sales returns and warranty claims have historically not been material and do not constitute separate performance obligations. We often enter into agreements with our customers to offer incentive programs, primarily volume rebates and promotions. The majority of our rebates are designated as a percentage of annual customer purchases. We estimate the amount of rebate based on actual sales for the period and accrue for the projected incentive programs costs. We record the costs of the rebate accruals as a reduction to our revenue. In addition, other sales discounts, including early pay promotions, are deducted immediately from the sales invoice.
Shipping and Handling	Shipping and Handling We account for product shipping and handling costs as fulfillment activities and present the associated costs in costs of goods sold in the period in which we sell our product.