Subsequent Events	6 Months Ended
Jun. 30, 2017
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On July 3, 2017, the Company acquired Drexel Metals, Inc., ("Drexel") for estimated consideration of $54.0 million, net of cash acquired and to be adjusted for a working capital settlement. Drexel is a leading provider of architectural standing seam metal roofing systems for commercial, institutional and residential applications. The preliminary purchase price allocation is in its early stages and all items are pending valuation. The results of operations of the acquired business will be reported within the Construction Materials segment.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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