Segments (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Assets	$ 3,994us-gaap_Assets	$ 4,121us-gaap_Assets
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	731
USG Boral Building Products
Segment Reporting Information [Line Items]
Net sales	927
Depreciation, depletion, and amortization	31
Capital expenditures	40
Assets	1,435
USG Boral Building Products \| Reportable Geographical Components \| Australia
Segment Reporting Information [Line Items]
Net sales	312
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	245
USG Boral Building Products \| Reportable Geographical Components \| South Korea
Segment Reporting Information [Line Items]
Net sales	197
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	113
USG Boral Building Products \| Reportable Geographical Components \| China
Segment Reporting Information [Line Items]
Net sales	122
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	127
USG Boral Building Products \| Reportable Geographical Components \| Oman
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	96
USG Boral Building Products \| Reportable Geographical Components \| Thailand
Segment Reporting Information [Line Items]
Net sales	133
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	72
USG Boral Building Products \| Reportable Geographical Components \| Other
Segment Reporting Information [Line Items]
Net sales	206
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	78
USG Boral Building Products \| Geographic transfers
Segment Reporting Information [Line Items]
Net sales	(43)
USG Boral Building Products \| USG Boral Building Products
Segment Reporting Information [Line Items]
Net sales	927
Operating profit	95
Net income attributable to UBBP	$ 67

Equity Method Investment Summarized Financial Information Capital Expenditures

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- Definition

Equity Method Investment Summarized Financial Information Depreciation Depletion Amortization

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Equity Method Investment, Summarized Financial Information, Long Lived Assets

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Equity Method Investment Summarized Financial Information Net Income Loss Attributable to Parent

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- Definition

The amount of operating profit (loss) reported by an equity method investment of the entity.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.18)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 7

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 18

-Article 5

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The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

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No definition available.

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