Discontinued Operations (Details 4) - TopBuild - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014
Selected financial information of discontinued operations
Depreciation and amortization	$ 6	$ 19
Capital expenditures	$ 7	$ 9

Amount of depreciation and amortization attributable to disposal group.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration