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Oman Investment (Details Textual) (USD $)
In Millions, unless otherwise specified
 12 Months Ended
Dec. 31, 2014
Jun. 30, 2012
Dec. 31, 2013
Zawawi Gypsum LLC      
Noncontrolling Interest [Line Items]      
Ownership percentage by parent   55.00%us-gaap_MinorityInterestOwnershipPercentageByParent
/ dei_LegalEntityAxis
= usg_ZawawiGypsumLlcMember		  
USG-Zawawi Drywall LLC      
Noncontrolling Interest [Line Items]      
Ownership percentage by parent 50.00%us-gaap_MinorityInterestOwnershipPercentageByParent
/ dei_LegalEntityAxis
= usg_UsgZawawiDrywallLlcMember		    
Percentage of noncontrolling owners in VIE 50.00%us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
/ dei_LegalEntityAxis
= usg_UsgZawawiDrywallLlcMember		    
Zawawi Gypsum LLC and USG-Zawawi Drywall LLC [Member]      
Noncontrolling Interest [Line Items]      
Decrease in non-controlling interest $ 24us-gaap_NoncontrollingInterestDecreaseFromDeconsolidation
/ dei_LegalEntityAxis
= usg_ZawawiGypsumLLCandUSGZawawiDrywallLLCMember		    
Zawawi Gypsum LLC and USG-Zawawi Drywall LLC [Member] | Co-venturer      
Noncontrolling Interest [Line Items]      
Loans payable due to joint venture partner     $ 8us-gaap_NotesPayableRelatedPartiesNoncurrent
/ dei_LegalEntityAxis
= usg_ZawawiGypsumLLCandUSGZawawiDrywallLLCMember
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= us-gaap_CoVenturerMember