Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959

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Balance Type:	credit
Period Type:	instant

- Definition

Nominal energy measure used to calculate payments on a derivative instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:energyItemType
Balance Type:	na
Period Type:	duration

- Definition

The loss recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

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

- Definition

Typical hedging period

+ References

No definition available.

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- Details

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- Details

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- Details

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- Details

Name:	usg_HedgedItemAxis=usg_PurchasesofproductsandservicesMember
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Derivative Instruments - Narrative (Details) MMBTU in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) MMBTU	Sep. 30, 2017 USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Typical hedging period			5 years
Net liability aggregate fair value	$ 11,000,000		$ 11,000,000
Collateral provided to counterparties related to derivatives	9,000,000		$ 9,000,000
Cash flow hedging \| Commodity contracts
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount of commodity instruments (in mmbtu) \| MMBTU			45
Loss on cash flow hedge ineffectiveness	0	$ 0	$ 0	$ 0
Cash flow hedging \| Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Loss on cash flow hedge ineffectiveness	0	$ 0	0	$ 0
Purchases of products and services \| Cash flow hedging \| Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Notional amounts of foreign exchange forward contracts	$ 108,000,000		$ 108,000,000