Subsequent Events	12 Months Ended
Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	—Subsequent Events On January 11, 2019, the Company completed the acquisition of Petersen Aluminum Corporation ("Petersen") for approximately $197.0 million in cash, subject to post-closing adjustments. Petersen’s primary business is the manufacture and distribution of market leading architectural metal roof panels, steel and aluminum flat sheets and coils, wall panels, perimeter roof edge systems and related accessories for commercial, residential, institutional, industrial and agricultural markets. The initial accounting for the business combination is incomplete as a result of the timing of the acquisition. The results of operations of the acquired business will be reported within the CCM segment beginning in the first quarter of 2019.

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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