Inventories Inventories (Policies)	12 Months Ended
Dec. 31, 2019
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories consist principally of materials purchased for resale, including lumber, sheet goods, millwork, doors and windows, as well as certain manufactured products and are valued at the lower of cost or net realizable value, with cost being measured using a weighted average cost approach, which approximates the first-in, first-out approach.

Disclosure of inventory accounting policy for inventory classes, including, but not limited to, basis for determining inventory amounts, methods by which amounts are added and removed from inventory classes, loss recognition on impairment of inventories, and situations in which inventories are stated above cost.

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-Name Accounting Standards Codification
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-SubTopic 10
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-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
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