Usg (USG) 10-K 10 Feb 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2015	Jan. 31, 2016	Jun. 30, 2015
Document and Entity Information [Abstract]
Entity Registrant Name	USG CORP
Entity Central Index Key	757,011
Document Type	10-K
Document Period End Date	Dec. 31, 2015
Amendment Flag	false
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 2,397,161,732
Entity Common Stock, Shares Outstanding		145,669,400

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Net sales	$ 3,776	$ 3,724	$ 3,570
Cost of products sold	3,085	3,070	2,989
Gross profit	691	654	581
Selling and administrative expenses	317	339	320
Litigation settlement charge	0	48	0
Long-lived asset impairment charges	0	90	0
Contract termination charge and (recovery) loss on receivable	(6)	15	0
Gain on disposal of shipping operations, net	(1)	0	0
Restructuring charges	0	0	3
Operating profit	381	162	258
Income (loss) from equity method investments	48	33	(1)
Interest expense	(163)	(179)	(203)
Interest income	2	1	3
Income and gain from the sale of equity method investment to related party	13	2	2
Gain on deconsolidation of subsidiaries and consolidated joint ventures	0	27	0
Loss on extinguishment of debt	(19)	0	0
Income from continuing operations before income taxes	262	46	59
Income tax benefit (expense)	729	(7)	(11)
Income from continuing operations	991	39	48
Loss from discontinued operations, net of tax	0	(1)	(2)
Net income	991	38	46
Less: Net income (loss) attributable to noncontrolling interest	0	1	(1)
Net income attributable to USG	$ 991	$ 37	$ 47
Earnings per common share - basic:
Income from continuing operations (in dollars per share)	$ 6.81	$ 0.27	$ 0.45
Loss from discontinued operations (in dollars per share)	0	(0.01)	(0.02)
Net income (in dollars per share)	6.81	0.26	0.43
Earnings per common share - diluted:
Income from continuing operations (in dollars per share)	6.73	0.26	0.44
Loss from discontinued operations (in dollars per share)	0	(0.01)	(0.02)
Net income (in dollars per share)	$ 6.73	$ 0.25	$ 0.42
Average common shares (in shares)	145,457,208	141,722,616	108,891,703
Average diluted common shares (in shares)	147,246,600	144,296,316	111,434,543

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 991	$ 38	$ 46
Derivatives qualifying as cash flow hedges:
Gain (loss) on derivatives qualifying as cash flow hedges, net of tax of $4, $0, and $0, respectively	(5)	(15)	4
Less: Reclassification adjustment for (loss) gain on derivatives included in net income, net of tax of $2, $0, and $0, respectively	(9)	4	1
Derivatives qualifying as cash flow hedges, net of tax of $2, $0, and $0, respectively	4	(19)	3
Pension and postretirement benefits:
Changes in pension and postretirement benefits, net of tax (benefit) of $6, ($2) and $10, respectively	74	(272)	247
Less: Amortization of prior service benefit cost included in net periodic pension cost, net of tax (benefit) of ($1), ($1) and ($2), respectively	(7)	(2)	(24)
Pension and postretirement benefits, net of tax (benefit) of $7, ($1) and $12, respectively	81	(270)	271
Foreign currency translation:
Changes in foreign currency translation, net of tax of $0 in all periods	(67)	(68)	(17)
Less: Translation (loss) gain realized upon sale of foreign entities, net of tax of $0 in all periods	(6)	5	0
Foreign currency translation, net of tax of $0 in all periods	(61)	(73)	(17)
Other comprehensive income (loss), net of tax	24	(362)	257
Comprehensive income (loss)	$ 1,015	$ (324)	$ 303

Consolidated Statements of Com4

Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax Effect [Abstract]
Gain (loss) on derivatives qualifying as cash flow hedges, net of tax (benefit)	$ 4	$ 0	$ 0
Less: Reclassification adjustment for gain (loss) on derivatives included in net income, net of tax (benefit)	2	0	0
Derivatives qualifying as cash flow hedges, net of tax (benefit)	2	0	0
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax [Abstract]
Changes in pension and postretirement benefits, net of tax (benefit)	6	(2)	10
Less: Amortization of prior service benefit (cost) included in net periodic pension cost, net of tax (benefit)	(1)	(1)	(2)
Pension and postretirement benefits, net of tax benefit	7	(1)	12
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax [Abstract]
Changes in foreign currency translation, net of tax	0	0	0
Less: Translation gains realized upon sale of foreign entities, net of tax	0	0	0
Foreign currency translation, net of tax	$ 0	$ 0	$ 0

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Current Assets:
Cash and cash equivalents	$ 442	$ 228
Short-term marketable securities	194	96
Restricted cash	9	1
Receivables (net of reserves: 2015 - $14; 2014 - $22)	391	404
Inventories	314	329
Income taxes receivable	5	3
Other current assets	45	48
Total current assets	1,400	1,109
Long-term marketable securities	36	58
Property, plant and equipment, net	1,788	1,908
Deferred income taxes	728	18
Equity method investments	682	735
Other assets	102	108
Total assets	4,736	3,936
Current Liabilities:
Accounts payable	259	290
Accrued expenses	214	220
Current portion of long-term debt	500	4
Income taxes payable	9	1
Litigation settlement accrual	9	48
Total current liabilities	991	563
Long-term debt	1,675	2,191
Deferred income taxes	5	17
Pension and other postretirement benefits	392	491
Other liabilities	237	266
Total liabilities	3,300	3,528
Stockholders’ Equity:
Preferred stock – $1 par value, authorized 36,000,000 shares; outstanding - none	0	0
Common stock – $0.10 par value; authorized 200,000,000 shares; issued: 2015 - 145,667,000 shares; 2014 - 144,768,000 shares	15	14
Additional paid-in capital	3,027	3,014
Accumulated other comprehensive income (loss)	(314)	(338)
Retained earnings (accumulated deficit)	(1,292)	(2,283)
Stockholders' equity of parent	1,436	407
Noncontrolling interest	0	1
Total stockholders’ equity including noncontrolling interest	1,436	408
Total liabilities and stockholders’ equity	$ 4,736	$ 3,936

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Reserves on receivables	$ 14	$ 22
Preferred stock - par value (in dollars per share)	$ 1	$ 1
Preferred stock - authorized shares (in shares)	36,000,000	36,000,000
Preferred stock - outstanding shares (in shares)	0	0
Common stock - par value (in dollars per share)	$ 0.1	$ 0.1
Common stock - authorized shares (in shares)	200,000,000	200,000,000
Common stock - issued shares (in shares)	145,667,000	144,768,000

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating Activities
Net income	$ 991	$ 38	$ 46
Loss from discontinued operations	0	(1)	(2)
Income from continuing operations	991	39	48
Adjustments to reconcile net income to net cash:
Depreciation, depletion, and amortization	142	154	155
Loss on extinguishment of debt	19	0	0
Litigation settlement charge	0	48	0
Long-lived asset impairment charges	0	90	0
Contract termination charge and (recovery) loss on receivable	(6)	15	0
Share-based compensation expense	15	21	19
Deferred income taxes	(731)	4	2
Provision for bad debt	0	1	0
Gain on asset dispositions	(15)	(12)	(1)
Gain from the sale of equity method investment to related party	(6)	0	0
Income from equity method investments	(50)	(35)	(1)
Dividends received from equity method investments	38	0	0
Pension settlement	1	13	16
Gain on deconsolidation of subsidiaries and consolidated joint ventures	0	(27)	0
(Increase) decrease in working capital, net of deconsolidation of subsidiaries and consolidated joint ventures:
Receivables	10	(49)	(44)
Income taxes receivable	(3)	3	(1)
Inventories	14	(9)	(28)
Other current assets	2	2	(4)
Payables	(15)	10	(4)
Accrued expenses	(60)	(12)	(23)
Decrease (increase) in other assets	5	3	(6)
Decrease in pension and other postretirement benefits	(28)	(55)	(63)
Decrease in other liabilities	(12)	(13)	(6)
Other, net	20	(18)	21
Net cash provided by operating activities	331	173	80
Investing Activities
Purchases of marketable securities	(246)	(204)	(205)
Sales or maturities of marketable securities	170	190	194
Capital expenditures	(94)	(132)	(124)
Acquisition of mining rights	0	0	(17)
Net proceeds from asset dispositions	61	16	2
Net proceeds from the sale of equity method investment to related party	52	0	0
Investments in joint ventures, including $23 of cash of contributed subsidiaries in 2014	0	(560)	(5)
Insurance proceeds	2	3	2
Return (deposit) of restricted cash	(8)	4	(4)
Net cash used for investing activities	(63)	(683)	(157)
Financing Activities
Issuance of debt	350	3	361
Repayment of debt	(386)	(63)	(4)
Payment of debt issuance fees	(6)	(3)	(6)
Loan from venture partner	0	0	4
Issuances of common stock	6	4	4
Repurchases of common stock to satisfy employee tax withholding obligations	(8)	(7)	(9)
Net cash (used for) provided by financing activities	(44)	(66)	350
Effect of exchange rate changes on cash	(10)	(5)	(7)
Net cash used for operating activities - discontinued operations	0	(1)	(2)
Net increase (decrease) in cash and cash equivalents	214	(582)	264
Cash and cash equivalents at beginning of period	228	810	546
Cash and cash equivalents at end of period	442	228	810
Supplemental Cash Flow Disclosures:
Interest paid, net of interest capitalized	158	172	192
Income taxes paid, net of refunds received	0	7	10
Noncash Investing and Financing Activities:
Amount in accounts payable for capital expenditures	5	15	13
Contribution of wholly-owned subsidiaries and joint venture investments as consideration for investment in USG Boral Building Products	0	121	0
Conversion of $75 million and $325 million, respectively, of 10% convertible senior notes due 2018, net of discount	0	(73)	(314)
Issuance of common stock upon conversion of debt	0	75	313
Acceleration of deferred financing fee amortization to additional paid-in capital	0	0	1
Accrued interest on debt conversion	$ 0	$ (2)	$ 0

Consolidated Statements of Cas8

Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Cash held by subsidiaries contributed to joint venture	$ 23
10% convertible senior notes due 2018
Converted debt aggregate principal amount	$ 75	$ 325

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Millions	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings (Deficit)	Accumulated Other Comprehensive Income (Loss)	Stockholders' Equity	Non-controlling Interest
Balance at beginning of period at Dec. 31, 2012	$ 19	$ 11	$ 0	$ 2,595	$ (2,367)	$ (233)	$ 6	$ 13
Balance at beginning of period (in shares) at Dec. 31, 2012		107,851	(1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	46				47		47	(1)
Other comprehensive income (loss)	257					257	257
Share-based compensation	19			19			19
Stock issuances	5	$ 0	$ 9	(4)			5
Stock issuances (in shares)		954	314
Stock issuances upon debt conversion	313	$ 3		310			313
Stock issuances upon debt conversion (in shares)		28,509
Repurchase of common stock	(9)		$ (9)				(9)
Repurchase of common stock (in shares)			(313)
Changes in noncontrolling interest	12						0	12
Balance at end of period at Dec. 31, 2013	662	$ 14	$ 0	2,920	(2,320)	24	638	24
Balance at end of period (in shares) at Dec. 31, 2013		137,314	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	38				37		37	1
Other comprehensive income (loss)	(362)					(362)	(362)
Share-based compensation	21			21			21
Stock issuances	5	$ 0	$ 4	1			5
Stock issuances (in shares)		947	166
Stock issuances upon debt conversion	75	$ 0	$ 3	72			75
Stock issuances upon debt conversion (in shares)		6,507	72
Repurchase of common stock	(7)		$ (7)				(7)
Repurchase of common stock (in shares)			(238)
Changes in noncontrolling interest	(24)						0	(24)
Balance at end of period at Dec. 31, 2014	408	$ 14	$ 0	3,014	(2,283)	(338)	407	1
Balance at end of period (in shares) at Dec. 31, 2014		144,768	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	991				991		991	0
Other comprehensive income (loss)	24					24	24
Share-based compensation	15			15			15
Stock issuances	7	$ 1	$ 8	(2)			7
Stock issuances (in shares)		899	283
Stock issuances upon debt conversion	0
Repurchase of common stock	(8)		$ (8)				(8)
Repurchase of common stock (in shares)			(283)
Changes in noncontrolling interest	(1)						0	(1)
Balance at end of period at Dec. 31, 2015	$ 1,436	$ 15	$ 0	$ 3,027	$ (1,292)	$ (314)	$ 1,436	$ 0
Balance at end of period (in shares) at Dec. 31, 2015		145,667	0

Significant Accounting Policies

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies Nature of Operations USG, through its subsidiaries, is a leading manufacturer and distributor of building materials. We produce a wide range of products for use in new residential, new nonresidential, and residential and nonresidential repair and remodel construction as well as products used in certain industrial processes. Our products also are distributed through building materials dealers, home improvement centers and other retailers, specialty wallboard distributors, and contractors. Segments Our segments are structured around our key products and business units: Gypsum, Ceilings, Distribution and UBBP. Our Gypsum reportable segment is an aggregation of the operating segments of the gypsum businesses in the United States, Canada, Mexico, and Latin America, our mining operation in Little Narrows, Nova Scotia, Canada, and our shipping company, which we exited in 2015. Gypsum manufactures products throughout the United States, Canada, and Mexico. These products include USG Sheetrock ® brand gypsum wallboard and related products including Sheetrock ® brand joint compound, Durock ® brand cement board, Levelrock ® brand of poured gypsum flooring, Fiberock ® brand backerboard, and Securock ® brand glass mat sheathing used for building exteriors and gypsum fiber and glass mat panels used as roof cover board. Ceilings manufactures ceiling tile in the United States and ceiling grid in the United States, Canada and through February 27, 2014, the Asia-Pacific region. Distribution delivers gypsum wallboard, drywall metal, ceilings products, joint compound and other building products throughout the United States. UBBP manufactures, distributes and sells certain building products, mines raw gypsum and sells natural and synthetic gypsum throughout Asia, Australasia and the Middle East. Consolidation and Presentation Our consolidated financial statements include the accounts of USG Corporation, its majority-owned subsidiaries and through February 27, 2014, variable interest entities. Entities in which we have more than a 20% but not more than 50% ownership interest are accounted for using the equity method of accounting. All intercompany balances and transactions are eliminated in consolidation. On our consolidated statements of operations for the year ended December 31, 2013, income from equity method investments, which was previously included in "Other income, net," is reflected as "Income (loss) from equity method investments" and long-lived asset impairment charges, which was previously included in "Restructuring and long-lived asset impairment charges," are reflected as "Long-lived asset impairment charges" to conform to the current year presentation. On our consolidated statements of cash flows for the year ended December 31, 2013, income from equity method investments previously included in "Other, net" has been reclassified to "Income (loss) from equity method investments." On September 15, 2015, we entered into an agreement to sell our 50% interest in the Knauf-USG joint venture to our joint venture partner and completed the sale in December 2015. On our consolidated statements of operations for the years ended December 31, 2014 and 2013, income from this equity method investment, which was previously included in "Income from equity method investments" is reflected as "Income and gain from the sale of equity method investment to related party" to conform to the current year presentation. Presentation of this income on the consolidated statement of cash flows is within "Income from equity method investments." Our investments with Boral in the 50 / 50 joint ventures, UBBP, commenced on February 27, 2014, and as a result, our share of ten months of the results of UBBP were recorded in our accompanying consolidated statement of operations for the year ended December 31, 2014. See Note 3 for further description of our investments in UBBP. Use of Estimates The preparation of our consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions. These estimates and assumptions affect the reported amounts of assets, liabilities, revenues and expenses. Actual results could differ from these estimates. Revenue Recognition We recognize revenue when substantially all the risks and rewards of ownership transfer to the customer. We record provisions for discounts to customers based on the terms of sale in the same period in which the related sales are recorded. We record estimated reductions to revenue for customer programs and incentive offerings, including promotions and other volume-based incentives, in the period in which the sale occurs. Shipping and Handling Costs Shipping and handling costs are included in cost of products sold. Advertising Advertising expenses consist of media advertising and related production costs and sponsorships. We charge advertising expenses to earnings as incurred. These expenses amounted to $ 17 million , $ 23 million and $22 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. Research and Development We charge research and development expenditures to earnings as incurred. These expenditures amounted to $23 million , $23 million and $21 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. Litigation Costs We expense litigation costs as incurred. Income Taxes We record income tax expense (benefit) under the asset and liability method. Under this method, deferred tax assets and liabilities are recognized based on temporary differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply in the years in which the temporary differences are expected to be recovered or paid. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in earnings in the period when the change is enacted. Valuation allowances are recorded to reduce deferred tax assets when it is more likely than not that a tax benefit will not be realized. Inventory Valuation All of our inventories are stated at the lower of cost or market. Virtually all of our inventories are valued under the average cost method with the remainder valued under the first-in, first-out cost method. Our manufactured inventories include materials, labor and applicable factory overhead costs whereas our distribution inventories are valued at their cost. Depreciation associated with manufacturing assets is excluded from inventory cost, but is included in cost of products sold. Earnings per Share Basic earnings per share is based on the weighted average number of common shares outstanding. Diluted earnings per share is based on the weighted average number of common shares outstanding plus the dilutive effect, if any, of market share units, or MSUs, restricted stock units, or RSUs, and performance shares, and the potential exercise of outstanding stock options. Prior to the conversion of our 10% convertible senior notes, the dilutive effect of the potential conversion of the 10% convertible senior notes was included for the appropriate time periods when these instruments were outstanding. Cash and Cash Equivalents Cash and cash equivalents include highly liquid investments, primarily money market funds, with maturities of three months or less at the time of purchase. Marketable Securities Marketable securities are classified as available-for-sale securities and reported at fair value, with unrealized gains and losses excluded from earnings and reported in accumulated other comprehensive income (loss), or AOCI. If it is deemed that marketable securities have unrealized losses that are other than temporary, these losses will be recorded in earnings immediately. Situations in which losses may be considered other than temporary include when we have decided to sell a security or when it is more likely than not that we will be required to sell the security before we recover its amortized cost basis. Cost basis for securities sold are determined on a first-in-first-out basis. Receivables We include trade receivables in receivables on our consolidated balance sheets. Receivables are recorded at net realizable value, which includes allowances for cash discounts and doubtful accounts. We review the collectability of receivables on an ongoing basis. We reserve for receivables determined to be uncollectible. This determination is based on the delinquency of the account, the financial condition of the customer and our collection experience. We include short-term financing receivables in receivables and long-term financing and loan receivables in other assets on our consolidated balance sheets. Financing and loan receivables are recorded at net realizable value which includes an allowance for credit losses. We review the collectability of financing and loan receivables on an ongoing basis. We reserve for financing and loan receivables determined to be uncollectible. This determination is based on the delinquency of the account and the financial condition of the other party. As of December 31, 2015 , the allowance for credit losses was immaterial. Investments in Unconsolidated Joint Ventures The equity method of accounting is used for investments in joint ventures that we do not consolidate, but over which we have the ability to exercise significant influence. Profits resulting from sales with equity method investees are eliminated until realized by the investee. Losses in the value of an investment in an unconsolidated joint venture that are other than temporary, are recognized when the current fair value of the investment is less than its carrying value. Property, Plant and Equipment Property, plant and equipment is recorded at cost. We record depreciation of property, plant and equipment on a straight-line basis over the expected useful lives of the assets. We have determined estimated useful lives to be 50 years for buildings and improvements, a range of 10 to 25 years for machinery and equipment, and a range of 5 to 7 years for computer software and systems development costs. Leasehold improvements are capitalized and amortized over the shorter of the remaining lease term or remaining economic useful life. We compute depletion on a basis calculated to spread the cost of gypsum and other applicable resources over the estimated quantities of material recoverable. We capitalize interest during the active construction period of major capital projects. Capitalized interest is added to the cost of the underlying assets and is depreciated over the useful lives of those assets. We recorded $3 million of capitalized interest in each of the three years ended December 31, 2015 . Facility start-up costs that cannot be capitalized are expensed as incurred and recorded in cost of products sold. Property, plant and equipment is reviewed for impairment when indicators of a potential impairment are present by comparing the carrying values of the assets with their estimated future undiscounted cash flows. If we determine an impairment exists, the asset is written down to estimated fair value. Intangible Assets We perform impairment tests for intangible assets with indefinite useful lives as of October 31 of each year, or more frequently if events occur or circumstances change that would more likely than not reduce the fair value of an intangible asset below its carrying value. The impairment test for assets with indefinite lives consists of a comparison of the fair value of the asset with its carrying amount. If the carrying amount of an intangible asset exceeds its fair value, an impairment loss is recognized in an amount equal to that excess. Intangible assets determined to have indefinite useful lives, primarily comprised of trade names, are not amortized. An income approach is used for valuing trade names. Assumptions used in the income approach include projected revenues and assumed royalty, long-term growth and discount rates. We perform impairment tests on definite lived intangible assets, such as customer relationships, upon identification of events or circumstances that may indicate the carrying amount of the assets might be unrecoverable by comparing their undiscounted cash flows with their carrying value. If we determine impairment exists, the assets are written down to estimated fair value. As of December 31, 2015 , we had no intangible assets in other current assets on the consolidated balance sheet classified as assets held for sale. As of December 31, 2014 , we had $5 million of intangible assets classified as assets held for sale. Share-Based Compensation We award share-based compensation to employees in the form of stock options, restricted stock units, market share units, and performance shares and to non-employee directors in the form of shares of our common stock. All grants under share-based payment programs are accounted for at fair value at the date of grant. We recognize expense on all share-based awards to employees expected to vest over the service period, which is the shorter of the period until the employees’ retirement eligibility dates or the service period of the award. Derivative Instruments We use derivative instruments to manage selected commodity price and foreign currency exposures. We do not use derivative instruments for speculative trading purposes, and we typically do not hedge beyond three years . All derivative instruments are recorded on the balance sheet at fair value. For derivatives designated as fair value hedges, the changes in the fair values of both the derivative instrument and the hedged item are recognized in earnings in the current period. For derivatives designated as cash flow hedges, the effective portion of changes in the fair value of the derivative is recorded to AOCI, and is reclassified to earnings when the underlying forecasted transaction affects earnings. The ineffective portion of changes in the fair value of the derivative is reported in cost of products sold in the current period. We periodically reassess the probability of the underlying forecasted transaction occurring. For derivatives designated as net investment hedges, we record changes in fair value to AOCI. For derivatives not designated as hedging instruments, all changes in fair value are recorded to earnings in the current period. Currently, we are using swaps to hedge a significant portion of our anticipated purchases of natural gas to be used in our manufacturing operations. Generally, we hedge the cost of a majority of our anticipated purchases of natural gas over the next 12 months . However, we review our positions regularly and make adjustments as market conditions warrant. The majority of contracts currently in place are designated as cash flow hedges and the remainder are not designated as hedging instruments. We have operations outside of the United States and use forward contracts from time-to-time to hedge the risk of changes in cash flows resulting from selected forecasted intercompany and third-party sales or purchases, as well as intercompany loans, denominated in non-U.S. currencies, or to hedge the risk of selected changes in our net investment in foreign subsidiaries. These contracts are designated as either cash flow or net investment hedges or are not designated as hedging instruments. Foreign Currency Translation We translate foreign-currency-denominated assets and liabilities into U.S. Dollars at the exchange rates existing as of the respective balance sheet dates. We translate income and expense items at the average exchange rates during the respective periods. We record translation adjustments resulting from fluctuations in exchange rates to AOCI on our consolidated balance sheets and our share of the translation adjustments recorded by our equity method investments to AOCI. We record transaction gains and losses to earnings. The total transaction loss was $7 million in 2015 , $6 million in 2014 and $4 million in 2013 . Fair Value Measurements Certain assets and liabilities are required to be recorded at fair value. The estimated fair values of those assets and liabilities have been determined using market information and valuation methodologies. Changes in assumptions or estimation methods could affect the fair value estimates. However, we do not believe any such changes would have a material impact on our financial condition, results of operations or cash flows. There are three levels of inputs that may be used to measure fair value: • Level 1 – Quoted prices for identical assets and liabilities in active markets; • Level 2 – Quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; and model-derived valuations in which all significant inputs and significant value drivers are observable in active markets; and • Level 3 – Valuations derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable. Certain assets and liabilities are measured at fair value on a nonrecurring basis rather than on an ongoing basis, but are subject to fair value adjustments in certain circumstances, such as when there is evidence of impairment or when a new liability is being established that requires fair value measurement.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	12 Months Ended
	Dec. 31, 2015
Accounting Changes and Error Corrections [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements In January 2016, the Financial Accounting Standards Board, or FASB, issued Accounting Standard Update, or ASU, 2016-01 “Recognition and Measurement of Financial Assets and Financial Liabilities,” which requires that most equity instruments be measured at fair value, with subsequent changes in fair value recognized in net income. The pronouncement also impacts the financial liabilities under the fair value option and the presentation and disclosure requirements for financial instruments. The ASU does not apply to equity method investments or investments in consolidated subsidiaries. The new standard will be effective for us for the year ended December 31, 2018, with early adoption permitted and amendments to be applied as a cumulative-effect adjustment to the balance sheet in the year of adoption. We are currently in the process of assessing the impact of the ASU on our consolidated financial statements and disclosures. In November 2015, the FASB issued ASU 2015-17, "Balance Sheet Classification of Deferred Taxes", which requires entities to present all deferred tax assets and liabilities as noncurrent. We early adopted the standard as of December 31, 2015 and have reclassified our current deferred tax assets and liabilities to long-term. For the year ended December 31, 2014, our consolidated balance sheet has been retrospectively adjusted to conform with the new presentation, which resulted in a reclassification of $1 million from current assets to long-term assets and $44 million from current assets to long-term liabilities. In July 2015, the FASB issued ASU 2015-11, "Simplifying the Measurement of Inventory", which changes the measurement principle for inventory from the lower of cost or market to the lower of cost or net realizable value for entities that measure inventory using the first-in, first-out (FIFO) or average cost method. The ASU defines net realizable value as estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The standard will be effective for us in the first quarter of 2017, with early adoption permitted. We do not expect the adoption of ASU 2015-11 will have a significant impact to our consolidated financial statements or disclosures. In May 2015, the FASB issued ASU 2015-07, "Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent)," which updates the disclosure requirements for investments that are measured at net asset value using the practical expedient. These investments are to be removed from the fair value hierarchy and shown as a reconciling item. The standard will be effective for us in the first quarter of 2016. The adoption will not have a significant impact to our disclosures. In April 2015, the FASB issued ASU 2015-03, "Simplifying the Presentation of Debt Issuance Costs", which requires costs related to a recognized debt liability to be presented on the consolidated balance sheet as a direct deduction from the debt liability rather than as an asset. In August 2015, the FASB issued ASU 2015-15, "Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements", which clarifies that the SEC staff would not object to an entity deferring and presenting debt issuance costs as an asset, regardless of whether there are any outstanding borrowings on the line-of-credit. We adopted these standards as of December 31, 2015 and have reclassified our deferred debt issuance costs associated with our debt other than our line-of-credit from other assets to debt. For the year ended December 31, 2014, our consolidated balance sheet has been adjusted to conform with the new presentation, which resulted in a reclassification of $14 million from other assets to debt. In August 2014, the FASB issued ASU 2014-15, "Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern," which requires, in connection with preparing financial statements for each annual and interim reporting period, management to evaluate whether there are conditions or events that raise substantial doubts about the entity's ability to continue as a going concern within one year after the date that the financial statements are issued and provide related disclosures. The standard will be effective for us in the first quarter of 2016. We do not expect that the adoption of ASU 2014-15 will have a significant impact to our disclosures. In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers,” which supersedes the revenue recognition requirements in “Revenue Recognition (Topic 605),” and requires entities to recognize revenue in a way that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled to in exchange for those goods or services. There are two transition methods available under the new standard, either cumulative effect or retrospective. The standard will be effective for us in the first quarter of 2018. We will adopt the new standard using the modified retrospective approach, which requires the standard be applied only to the most current period presented, with the cumulative effect of initially applying the standard recognized at the date of initial application. We are evaluating the effect of adopting this standard, but we do not expect that the adoption of ASU 2014-09 will have a significant impact to our consolidated financial statements or disclosures.

Equity Method Investments

Equity Method Investments	12 Months Ended
	Dec. 31, 2015
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	Equity Method Investments Equity method investments were as follows: December 31, 2015 December 31, 2014 (millions) Carrying Value Ownership Percentage Carrying Value Ownership Percentage USG Boral Building Products $ 675 50% $ 689 50% Other equity method investments (a) 7 33% - 50% $ 46 33% - 50% Total equity method investments $ 682 $ 735 (a) As of December 31, 2014, our investment in the Knauf-USG joint venture was $38 million . Investments in USG Boral Building Products (UBBP) On February 27, 2014, we formed the 50 / 50 joint ventures, USG Boral Building Products Pte. Limited, a company organized under the laws of Singapore, and USG Boral Building Products Pty Limited, a company organized under the laws of Australia, with Boral Limited, or Boral. These joint ventures are herein referred to as USG Boral Building Products, or UBBP. UBBP manufactures, distributes and sells certain building products, mines raw gypsum and sells natural and synthetic gypsum throughout Asia, Australasia and the Middle East (the "Territory"). The products that UBBP manufactures and distributes include products for wall, ceiling, floor lining and exterior systems that utilize gypsum wallboard, referred to as plasterboard in the Territory, mineral fiber ceiling tiles, steel grid and joint compound. As consideration for our 50% ownership in UBBP, we (i) made a cash payment of $515 million to Boral, which includes a $500 million base price and $15 million of customary estimated working capital and net debt adjustments, (ii) contributed to UBBP our subsidiaries and joint venture investments in China, Singapore, India, Malaysia, New Zealand, Australia, the Middle East and Oman and (iii) granted to UBBP licenses to use certain of our intellectual property rights in the Territory. We funded our cash payment with the net proceeds from our October 2013 issuance of $350 million of 5.875% senior notes and cash on hand. In the event certain performance targets are satisfied by UBBP, we will be obligated to pay Boral scheduled earnout payments in an aggregate amount up to $75 million , comprised first of $25 million based on performance during the first three years and then up to $50 million based on performance during the first five years . We recorded a liability representing the present value of the first earnout payment. If our conclusion on the probability were to change, we would reduce the liability with a corresponding reduction to our investment. We have not recorded a liability for the second earnout payment as we have concluded that it is currently not probable that the five-year performance target will be achieved. If our conclusion on the probability of achievement were to change, we will record a liability representing the present value of the second earnout payment with a corresponding increase to our investment. As of December 31, 2015 and 2014 , our liability for the earnout payments totaled $24 million and $23 million , respectively, and is included in other liabilities on our accompanying consolidated balance sheets. We account for our 50% investments in UBBP using the equity method of accounting, and we initially measured its carrying value at cost of approximately $676 million as of February 27, 2014. Our existing wholly-owned subsidiaries and consolidated variable interest entities that were contributed into the joint venture were deconsolidated resulting in a gain of $27 million , which is included in our consolidated statement of operations for the year ended December 31, 2014 . Approximately $11 million of the gain relates to the remeasurement of our retained investment in the contributed subsidiaries to fair value, determined using a discounted cash flow model with several inputs, including a weighted-average discount rate of approximately 11% and a weighted-average long-term growth rate of approximately 2% . All of our investments accounted for under the equity method of accounting are initially recorded at cost and subsequently adjusted for our share of the net income or loss and cash contributions and distributions to or from these entities. Because the underlying net assets in our investments are denominated in a foreign currency, translation gains or losses will impact the recorded value of our investments. Translation gains or losses recorded in other comprehensive income were as follows: (millions) 2015 2014 2013 Translation loss $ (23 ) $ (34 ) $ — During 2015 , UBBP paid cash dividends on earnings through October 2015 of which our 50% share totaled $38 million . We recorded the cash dividend in operating activities on our statements of cash flows and intend to use the cash dividends to fund the potential obligations under the earnout. As of December 31, 2015 , the amount of consolidated retained earnings which represents undistributed earnings from UBBP is $42 million . Investment in Knauf-USG Joint Venture On September 15, 2015, we entered into an agreement to sell our 50% interest in Knauf/USG Verwaltungs GmbH and Knauf/USG Systems GmbH & Co. KG, or collectively the Knauf-USG joint venture, to our joint venture partner, Knauf Aquapanel GmbH, a subsidiary of Gebr. Knauf Verwaltungsgesellschaft KG (Knauf) for €48 million in cash, or approximately $52 million . The Knauf-USG joint venture manufactured and distributed Aquapanel ® brand cement-based panels in Europe (excluding Turkey) and all countries that were part of the former Soviet Union. Affiliates of Knauf are the beneficial owners of approximately 10% of USG's outstanding shares of common stock. On December 22, 2015 the sale was completed and we recorded a gain of approximately $6 million , which is net of $5 million for income taxes payable on the sale. The gross gain and our equity method income in the Knauf-USG joint venture was $13 million for the year ended December 31, 2015 and $2 million for each of the years ended December 31, 2014 and 2013 and is recorded in "Income and gain from the sale of equity method investment to related party" in our consolidated statement of operations. Summarized Financial Information Summarized financial information for our equity method investments is as follows: Statement of Operations For the year ended December 31, (millions) 2015 2014 (a) 2013 USG Boral Building Products: Net sales $ 1,003 $ 927 N/A Gross profit 278 251 N/A Operating profit 124 95 N/A Net income from continuing operations 101 72 N/A Net income 101 72 N/A Net income attributable to USG Boral Building Products 96 67 N/A USG share of income from USG Boral Building Products 48 33 N/A Other equity method investments (b) : USG share of income from other investments accounted for using the equity method 2 2 1 Total income from equity method investments 50 35 1 (a) Operating results are presented for UBBP for the ten months months ended December 31, 2014 . (b) Amounts represent our share of income or loss from all equity method investments, other than UBBP. For the twelve months ended December 31, 2014, the amount reflected includes two months of our share of income from equity method investments from the joint ventures which we owned prior to being contributed to UBBP on February 27, 2014. Balance Sheet (millions) December 31, 2015 December 31, 2014 USG Boral Building Products: Current assets $ 368 $ 446 Non-current assets 935 989 Current liabilities (c) 197 245 Long-term debt (d) 40 46 Other non-current liabilities 17 21 Shareholders' equity (e) 1,049 1,123 (c) Includes the current portion of long-term debt of $16 million and $35 million as of December 31, 2015 and 2014 , respectively. (d) Includes term loans and credit facilities for the joint ventures in Oman which were contributed to UBBP in February 2014. The loans and credit facilities are guaranteed by us and the Zawawi Group in Oman. (e) Shareholders' equity includes $60 million and $70 million related to non-controlling interests as of December 31, 2015 and 2014 , respectively.

Marketable Securities

Marketable Securities	12 Months Ended
	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	Marketable Securities Our investments in marketable securities as of December 31, 2015 and 2014 consisted of the following: 2015 2014 (millions) Amortized Cost Fair Value Amortized Cost Fair Value Corporate debt securities $ 134 $ 134 $ 93 $ 93 U.S. government and agency debt securities 57 57 22 22 Asset-backed debt securities 21 21 17 17 Certificates of deposit 15 15 18 18 Municipal debt securities 3 3 4 4 Total marketable securities $ 230 $ 230 $ 154 $ 154 The realized and unrealized gains and losses as of and for the years ended December 31, 2015 , 2014 and 2013 were immaterial. Contractual maturities of marketable securities as of December 31, 2015 were as follows: (millions) Amortized Cost Fair Value Due in 1 year or less $ 194 $ 194 Due in 1-5 years 36 36 Total marketable securities $ 230 $ 230 Actual maturities may differ from the contractual maturities because issuers of the securities may have the right to prepay them.

Intangible Assets

Intangible Assets	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	Intangible Assets Intangible assets are included in other assets on the consolidated balance sheets. Intangible assets with definite lives are amortized. These assets are summarized as follows: As of December 31, 2015 As of December 31, 2014 (millions) Gross Carrying Amount Accumulated Amortization Net Gross Carrying Amount Accumulated Amortization Net Intangible Assets with Definite Lives: Customer relationships $ 70 $ (61 ) $ 9 $ 70 $ (54 ) $ 16 Other 9 (8 ) 1 9 (7 ) 2 Total $ 79 $ (69 ) $ 10 $ 79 $ (61 ) $ 18 The weighted average amortization periods are 10 years for customer relationships and 11 years for other intangible assets with definite lives. Total amortization expense was $8 million in 2015 and $7 million in 2014 and 2013 , respectively. Estimated annual amortization expense is as follows: (millions) 2016 2017 2018 and thereafter Estimated annual amortization expense $ 7 $ 2 $ 1 Intangible assets with indefinite lives are not amortized. The gross carry amounts of these assets as of December 31 are as follows: (millions) 2015 2014 Intangible Assets with Indefinite Lives: Trade names $ 22 $ 22 Other 8 8 Total $ 30 $ 30 In 2015 , 2014 and 2013 , there was no impairment for any of our intangible assets. As of December 31, 2014 , approximately $5 million of other indefinite-lived intangible assets met the criteria to be classified as held for sale and therefore were included in other current assets on our consolidated balance sheet. As of December 31, 2015 , these indefinite-lived intangible assets were no longer recorded as held for sale.

Debt

Debt	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Debt	Debt Total debt as of December 31 consisted of the following: (millions) 2015 2014 5.5% senior notes due 2025 $ 350 $ — 5.875% senior notes due 2021 350 350 6.3% senior notes due 2016 500 500 7.75% senior notes due 2018 500 500 7.875% senior notes due 2020 (net of discount: 2015 - $1; 2014 - $1) 249 249 8.375% senior notes due 2018 — 350 Ship mortgage facility (includes current portion of long-term debt: 2015 - $0; 2014 - $4) — 21 Industrial revenue bonds (due 2028 through 2034) 239 239 Total $ 2,188 $ 2,209 Less unamortized debt issuance costs (a) $ 13 $ 14 Total $ 2,175 $ 2,195 (a) Reflects the change in presentation of unamortized debt issuance costs from other assets to a reduction in debt. See Note 2 . Repurchase of 8.375% Senior Notes and Issuance of 5.5% Senior Notes In the first quarter of 2015, we repurchased $350 million of our 8.375% senior notes due in 2018 through both a cash tender offer and a subsequent notice of redemption. On February 24, 2015, we completed a cash tender offer pursuant to which we repurchased $126 million of the 8.375% senior notes for aggregate consideration, including tender offer premium and accrued and unpaid interest, of $135 million . On March 26, 2015, we repurchased the remaining $224 million of the 8.375% senior notes for aggregate consideration, including premiums and accrued and unpaid interest, of $242 million . As a result of the repurchases, we recorded a loss on early extinguishment of debt of $19 million including the write-off of unamortized debt issuance costs. Also on February 24, 2015, we issued $350 million of 5.5% senior notes due March 1, 2025. The net proceeds from the issuance of these notes and cash on hand were used to fund the repurchases of the 8.375% senior notes and all related costs and expenses. We deferred approximately $6 million of debt issuance costs that are being amortized to interest expense over the term of the notes. As of December 31, 2015 , these notes were recorded on the accompanying consolidated balance sheet at $344 million . Senior Notes All of the senior notes are senior unsecured obligations and rank equally with all of our other existing and future unsecured senior indebtedness. The indentures governing the notes contain events of default, covenants and restrictions that are customary for similar transactions, including a limitation on our ability and the ability of certain of our subsidiaries to create or incur secured indebtedness. Interest rate (a) 6.30% 7.75% 5.500% 7.875% 5.875% Principal net of discount (in millions) (b) $500 $500 $350 $249 $350 Maturity November 15, 2016 January 15, 2018 March 1, 2025 March 30, 2020 November 1, 2021 Call date Any time (c) Any time (c) March 1, 2020 (d) March 30, 2016 (d) November 1, 2016 (d) Mandatory redemption at 101% plus accrued and unpaid interest in the event of a change in control and a related downgrade below investment grade by both Moody’s Investors Service and Standard & Poor’s Financial Services LLC at 101% plus accrued and unpaid interest in the event of a change in control (a) The 7.75% senior notes currently have an effective interest rate of 9.75% . The rate is subject to an adjustment of up to 2% if the debt rating is downgraded or subsequently upgraded by Moody's Investors Service and Standard & Poor's Financial Services LLC. (b) Principal amounts do not include unamortized debt issuance costs that have been reclassified from other assets to a reduction in debt. See Note 2 . (c) Callable at any time at a price equal to the greater of (1) 100% of the principal and (2) the sum of the present value of the remaining scheduled payments of principal and interest discounted to the redemption date on a semi-annual basis at the applicable U.S. Treasury rate plus a spread (as outlined in the respective indentures), plus any accrued and unpaid interest on the principal amount being called. (d) Callable at any time prior to the call date at a price equal to 100% of the principal plus a premium (as outlined in the respective indentures), plus any accrued and unpaid interest on the principal amount being called. Callable after the call date at stated redemption prices (as outlined in the respective indentures), plus any accrued and unpaid interest on the principal amount being called. Credit Facility Our credit facility allows for a maximum borrowing limit under the credit agreement of $450 million (including a $50 million borrowing sublimit for CGC, Inc.). The agreement allows for the borrowing of revolving loans and issuance of letters of credit (up to a maximum of $200 million at any time outstanding, in aggregate) to USG and its subsidiaries. The maximum allowable borrowings may be increased at our request with the agreement of the lenders providing increased or new lending commitments, provided that the maximum allowable borrowings after giving effect to the increase may not exceed $650 million . Our obligations under the credit facility are guaranteed by USG and its significant domestic subsidiaries and secured by trade receivables and inventory. The credit facility matures on October 22, 2019 unless terminated earlier in accordance with its terms. The credit facility is available to fund working capital needs and for other general corporate purposes. The credit agreement contains a financial covenant that would require us to maintain a minimum fixed charge coverage ratio. Because we currently satisfy the required fixed charge coverage ratio, we are not required to maintain a minimum borrowing availability under the credit facility. The credit agreement contains other covenants and events of default that are customary for similar agreements and may limit our ability to take various actions including our ability to pay a dividend or repurchase our stock. Taking into account the most recent borrowing base calculation delivered under the credit facility, which reflects trade receivables and inventory as of December 31, 2015 , and outstanding letters of credit, borrowings available under the credit facility were approximately $295 million , including $50 million for CGC. As of December 31, 2015 and during the year then-ended, there were no borrowings under the facility. Had there been any borrowings as of that date, the applicable interest rate would have been 1.86% for loans in the US and 2.12% for loans in Canada. Outstanding letters of credit totaled $49 million , including $1 million for CGC, as of December 31, 2015 . Ship Mortgage Facility Our subsidiary, Gypsum Transportation Limited, or GTL, had a secured loan facility agreement with DVB Bank SE, as lender, agent and security trustee which was repaid during 2015 in connection with the sale of two self-unloading vessels. See Note 13 for discussion of GTL. Industrial Revenue Bonds Our $239 million of industrial revenue bonds have fixed interest rates ranging from 5.5% to 6.4% . The weighted average rate of interest on our industrial revenue bonds is 5.875% . These bonds mature during the years 2028 through 2034 . OTHER INFORMATION The fair value of our debt was $2.295 billion and $2.338 billion as of December 31, 2015 and 2014 , respectively, and was determined using the fair value hierarchy of inputs described in Note 1. The fair values were based on quoted prices for identical or similar liabilities in markets that are not active or valuation models in which all significant inputs and value drivers are observable and, as a result, are classified as Level 2. Interest accrued on our debt as of December 31, 2015 and December 31, 2014 was $45 million for both periods. As of December 31, 2015 , we were in compliance with the financial covenants contained in our credit facility. As of December 31, 2015 , the amounts of total debt outstanding maturing in each of the next five years and beyond were as follows: (millions) 2016 2017 2018 2019 2020 After 2020 Debt maturities (principal amounts) $ 500 $ — $ 500 $ — $ 250 $ 939

Derivative Instruments

Derivative Instruments	12 Months Ended
	Dec. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments COMMODITY DERIVATIVE INSTRUMENTS As of December 31, 2015 , we had 22 million mmBTUs (millions of British Thermal Units) in aggregate notional amount of outstanding natural gas swap contracts to hedge forecasted purchases. All of these contracts mature by December 31, 2017 . For contracts designated as cash flow hedges, the unrealized loss that remained in AOCI as of December 31, 2015 was $19 million and as of December 31, 2014 was $20 million . No ineffectiveness was recorded on contracts designated as cash flow hedges in 2015 , 2014 , or 2013 . Changes in fair value on contracts not designated as cash flow hedges are recorded to earnings. The fair value of those contracts not designated as cash flow hedges was a $2 million unrealized loss as of December 31, 2015 and a $5 million unrealized loss as of December 31, 2014 . FOREIGN EXCHANGE DERIVATIVE INSTRUMENTS We have foreign exchange forward contracts to hedge forecasted purchases of products and services denominated in foreign currencies. The notional amount of these contracts was $114 million as of December 31, 2015 , and they mature by December 27, 2017 . These forward contracts are designated as cash flow hedges and no ineffectiveness was recorded in 2015 , 2014 , or 2013 . The fair value of these contracts that remained in AOCI was an unrealized gain of $8 million and $3 million as of December 31, 2015 and December 31, 2014 , respectively. During the third quarter of 2015, we entered into foreign exchange forward contracts to hedge a portion of our net investment in our Knauf-USG joint venture. The notional amount of these contracts was $35 million and they matured on November 16, 2015. In November 2015, we entered into a similar foreign exchange forward contract with the same critical terms that was scheduled to mature on January 31, 2016. These forward contracts were designated as net investment hedges and no ineffectiveness was recorded. On December 22, 2015, we completed the sale and, as a result, we terminated the outstanding foreign exchange forward contract and reclassified the $1 million net gain realized for these contracts from AOCI to earnings which increased the gain on the sale of the equity method investment. See Note 3 for further discussion on the sale. COUNTERPARTY RISK, MASTER NETTING ARRANGEMENTS AND BALANCE SHEET OFFSETTING We are exposed to credit losses in the event of nonperformance by the counterparties to our derivative instruments. As of December 31, 2015 , our derivatives were in a $13 million net liability position. All of our counterparties have investment grade credit ratings; accordingly, we anticipate that they will be able to fully satisfy their obligations under the contracts. All of our derivative contracts are governed by master netting agreements negotiated between us and the counterparties that reduce our counterparty credit exposure. The agreements outline the conditions (such as credit ratings and net derivative fair values) upon which we, or the counterparties, are required to post collateral. As required by certain of our agreements, we had $21 million of collateral posted with our counterparties related to our derivatives as of December 31, 2015 . Amounts paid as cash collateral are included in receivables on our consolidated balance sheets. We have not adopted an accounting policy to offset fair value amounts related to derivative contracts under our master netting arrangements; therefore, individual derivative contracts are reflected on a gross basis, as either assets or liabilities, on our consolidated balance sheets, based on their fair value as of the balance sheet date. FINANCIAL STATEMENT INFORMATION The following are the pretax effects of derivative instruments on the consolidated statements of operations and the consolidated statements of comprehensive income (loss) for the years ended December 31, 2015 , 2014 and 2013 : Amount of Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on Derivatives (Effective Portion) Location of Gain or (Loss) Reclassified from AOCI into Income (Effective Portion) Amount of Gain or (Loss) Reclassified from AOCI into Income (Effective Portion) (millions) 2015 2014 2013 2015 2014 2013 Derivatives in Cash Flow Hedging Relationships Commodity contracts $ (14 ) $ (19 ) $ 1 Cost of products sold $ (15 ) $ 2 $ (2 ) Foreign exchange contracts 12 4 3 Cost of products sold 7 2 3 Foreign exchange contracts 1 — — Income and gain from the sale of equity method investment to related party 1 — — Total $ (1 ) $ (15 ) $ 4 $ (7 ) $ 4 $ 1 Location of Gain or (Loss) Recognized in Income on Derivatives Amount of Gain or (Loss) Recognized in Income on Derivatives (millions) 2015 2014 2013 Derivatives Not Designated as Hedging Instruments Commodity contracts Cost of products sold $ (3 ) $ (4 ) $ 2 Foreign exchange contracts Other (income) expense, net 2 — — Total $ (1 ) $ (4 ) $ 2 As of December 31, 2015 , we had no derivatives designated as net investment or fair value hedges. The following are the fair values of derivative instruments on the consolidated balance sheets as of December 31, 2015 and 2014 : Balance Sheet Location Fair Value Balance Sheet Location Fair Value (millions) 12/31/15 12/31/14 12/31/15 12/31/14 Derivatives in Cash Flow Hedging Relationships Commodity contracts Other current assets $ 1 $ 1 Accrued expenses $ 15 $ 14 Commodity contracts Other assets — — Other liabilities 5 7 Foreign exchange contracts Other current assets 8 3 Accrued expenses — — Total derivatives in hedging relationships $ 9 $ 4 $ 20 $ 21 Balance Sheet Location Fair Value Balance Sheet Location Fair Value (millions) 12/31/15 12/31/14 12/31/15 12/31/14 Derivatives Not Designated as Hedging Instruments Commodity contracts Other current assets $ — $ — Accrued expenses $ 2 $ 4 Commodity contracts Other assets — — Other liabilities — 1 Total derivatives not designated as hedging instruments $ — $ — $ 2 $ 5 Total derivatives Total assets $ 9 $ 4 Total liabilities $ 22 $ 26

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Certain assets and liabilities are required to be recorded at fair value. The fair values of our cash equivalents, equity mutual funds, marketable securities and derivatives were determined using the fair value hierarchy of inputs described in Note 1 . The cash equivalents, primarily consisting of money market funds, and equity mutual funds are valued based on quoted prices in active markets and, as a result, are classified as Level 1. Instruments classified as Level 2 are valued using income approach or market approach. We employ an income approach, such as discounted cash-flow method and use readily observable market data and internally developed valuation models when valuing our derivatives. The inputs for the valuation models are obtained from data providers and include end-of-period spot and forward natural gas prices and foreign currency exchange rates, natural gas price volatility and LIBOR and swap rates for discounting the cash flows implied from the derivative contracts. Marketable securities are valued using market value approaches, for example, pricing based on recent transactions. These values are based on quoted prices or other observable market inputs received from data providers. Our assets and liabilities measured at fair value on a recurring basis were as follows: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total (millions) 12/31/15 12/31/14 12/31/15 12/31/14 12/31/15 12/31/14 12/31/15 12/31/14 Cash equivalents $ 223 $ 93 $ 25 $ 32 $ — $ — $ 248 $ 125 Equity mutual funds 4 4 — — — — 4 4 Marketable securities: Corporate debt securities — — 134 93 — — 134 93 U.S. government and agency debt securities — — 57 22 — — 57 22 Asset-backed debt securities — — 21 17 — — 21 17 Certificates of deposit — — 15 18 — — 15 18 Municipal debt securities — — 3 4 — — 3 4 Derivative assets — — 9 4 — — 9 4 Derivative liabilities — — (22 ) (26 ) — — (22 ) (26 ) Certain assets and liabilities are measured at fair value on a nonrecurring basis rather than on an ongoing basis, but are subject to fair value adjustments in certain circumstances, such as when there is evidence of impairment or when a new liability is being established that requires fair value measurement. As disclosed in Note 12 , during 2014, we recorded asset impairment charges of $90 million . During 2014, we reviewed the carrying value of the ocean vessels owned by GTL for potential impairment by comparing the carrying value of those assets with their fair values. To determine the estimated fair value for the ocean vessels, we engaged a third-party ship broker. Management developed our estimate of fair value by considering comparable sales for similar asset types and incorporating an adjustment for the specialized nature of these assets. This fair value measurement is classified as Level 3, and, as disclosed in Notes 12 and 13 , we recorded a long-lived asset impairment charge of $60 million during the fourth quarter of 2014. Also during 2014, we reviewed our property, plant and equipment for potential impairment by comparing the carrying values of those assets with their fair values as estimated using the future undiscounted cash flows for their remaining useful lives. We measured the fair value of the machinery, equipment and buildings using measurements classified as Level 3, and, as disclosed in Note 12 , we recorded long-lived asset impairment charges of $30 million .

Employee Retirement Plans

Employee Retirement Plans	12 Months Ended
	Dec. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Employee Retirement Plans	Employee Retirement Plans We maintain defined benefit pension plans for most of our employees. Most of these plans require employee contributions in order to accrue benefits. Benefits payable under the plans are based on employees’ years of service and compensation during specified years of employment. Effective December 31, 2010, we amended the USG Corporation defined benefit pension plan to replace the final average pay formula with a cash balance formula for employees hired after that date. In 2013, we communicated to certain terminated vested participants in our USG Corporation Retirement Plan an option to receive a lump sum payment for their accrued benefits. The option commenced on October 1, 2013 and expired on November 15, 2013. For participants who elected this option, payments were made in December 2013, and we incurred a settlement charge of approximately $15 million , with a corresponding reduction in accumulated other comprehensive income (loss). We had maintained a pension plan for our subsidiary USG (U.K.) Ltd which had been previously frozen to permanently eliminate future benefit accruals. In December 2014, we irrevocably purchased annuities for the remaining deferred members of the plan relieving us of the responsibility of the pension benefit obligation, or PBO. Consequently, we recorded a settlement charge in selling and administrative expenses in the amount of $13 million and removed the net pension asset from our consolidated balance sheet. We also maintain plans that provide postretirement benefits (retiree health care and life insurance) for eligible employees. Employees hired before January 1, 2002 generally become eligible for the postretirement benefit plans when they meet minimum retirement age and service requirements. The cost of providing most postretirement benefits is shared with retirees. In 2011 and 2014, we amended our U.S. postretirement benefit plan to require retiree medical plan participants to begin purchasing individual coverage in the Affordable Insurance Exchanges or individual Medicare marketplace beginning January 1, 2016 using a company-funded subsidy. The subsidy will be determined based upon years of service at retirement and Medicare eligibility. The subsidy provided to retirees eligible for Medicare will end December 31, 2019. As a result of the amendments, the measurement of the accumulated postretirement benefit obligation, or APBO, was reduced and a credit to unrecognized prior service cost is being amortized into the statement of operations over the average remaining service of active plan participants to retirement eligibility. The components of net pension and postretirement benefit costs are summarized in the following table: (millions) 2015 2014 2013 Pension Benefits: Service cost of benefits earned $ 49 $ 37 $ 38 Interest cost on projected benefit obligation 66 65 63 Expected return on plan assets (83 ) (79 ) (76 ) Settlement (a) 1 13 16 Net amortization 39 24 43 Net pension cost $ 72 $ 60 $ 84 Postretirement Benefits: Service cost of benefits earned $ 2 $ 3 $ 3 Interest cost on projected benefit obligation 6 7 7 Net amortization (31 ) (35 ) (34 ) Net postretirement benefit $ (23 ) $ (25 ) $ (24 ) (a) In 2014, the settlement charge related to the elimination of the benefit obligation of the UK pension plan due to the purchase of annuities. In 2013, the settlement charge primarily related to lump sum payments made to certain terminated vested participants in our U.S. Plan. We use a December 31 measurement date for our plans. The accumulated benefit obligation, or ABO, for the defined benefit pension plans was $ 1.354 billion as of December 31, 2015 and $ 1.429 billion as of December 31, 2014 . As of December 31, (millions) 2015 2014 Selected information for pension plans with accumulated benefit obligations in excess of plan assets: Accumulated benefit obligation $ (1,182 ) $ (1,230 ) Fair value of plan assets 1,097 1,113 Selected information for pension plans with benefit obligations in excess of plan assets: Benefit obligation $ (1,365 ) $ (1,686 ) Fair value of plan assets 1,099 1,340 The following table summarizes projected benefit obligations, plan assets and funded status as of December 31: Pension Postretirement (millions) 2015 2014 2015 2014 Change in Benefit Obligation: Benefit obligation as of January 1 $ 1,686 $ 1,376 $ 167 $ 166 Service cost 49 37 2 3 Interest cost 66 65 6 7 Curtailment/settlements (4 ) (24 ) — — Participant contributions 11 10 3 8 Benefits paid (86 ) (81 ) (11 ) (20 ) Plan amendment — — — 4 Actuarial (gain) loss (119 ) 327 (14 ) 4 Foreign currency translation (39 ) (24 ) (9 ) (5 ) Benefit obligation as of December 31 $ 1,564 $ 1,686 $ 144 $ 167 Change in Plan Assets: Fair value as of January 1 $ 1,340 $ 1,262 $ — $ — Actual return on plan assets 17 132 — — Employer contributions 61 64 8 12 Participant contributions 11 10 3 8 Benefits paid (86 ) (81 ) (11 ) (20 ) Curtailment/settlements (4 ) (24 ) — — Foreign currency translation (38 ) (23 ) — — Fair value as of December 31 $ 1,301 $ 1,340 $ — $ — Funded status $ (263 ) $ (346 ) $ (144 ) $ (167 ) Components on the Consolidated Balance Sheets: Noncurrent assets $ 3 $ — $ — $ — Current liabilities (9 ) (9 ) (9 ) (13 ) Noncurrent liabilities (257 ) (337 ) (135 ) (154 ) Net liability as of December 31 $ (263 ) $ (346 ) $ (144 ) $ (167 ) Pretax Components in AOCI: Net actuarial loss $ 387 $ 490 $ 7 $ 24 Prior service credit (1 ) (1 ) (108 ) (140 ) Total as of December 31 $ 386 $ 489 $ (101 ) $ (116 ) For our defined benefit pension plans, the 2015 actuarial gain of $119 million was primarily due to an increase in the discount rates and the adoption of the new mortality tables published by the Society of Actuaries used to determine the benefit obligation. The weighted-average discount rate increased from 4.10% at December 31, 2014 to 4.43% at December 31, 2015 and decreased from 4.90% at December 31, 2013 to 4.10% at December 31, 2014 . For the defined benefit pension plans, we estimate that during 2016 we will amortize from AOCI into net pension cost a net actuarial loss of $ 19 million and no prior service cost . For the postretirement benefit plans, we estimate that during 2016 we will amortize from AOCI into net postretirement cost a net actuarial loss of $ 1 million and a prior service credit of $ 28 million . ASSUMPTIONS The following tables reflect the assumptions used in the accounting for our plans: Pension Postretirement 2015 2014 2015 2014 Weighted average assumptions used to determine benefit obligations as of December 31: Discount rate 4.43 % 4.10 % 4.24 % 3.70 % Compensation increase rate 3.55 % 3.60 % N/A N/A Weighted average assumptions used to determine net cost for years ended December 31: Discount rate 4.10 % 4.90 % 3.70 % 4.60 % Expected return on plan assets 6.70 % 7.00 % N/A N/A Compensation increase rate 3.50 % 3.50 % N/A N/A We no longer have significant exposure to health care cost trend rates due to the modifications we made to our U.S. postretirement health care plan to limit the increase in the annual amount we pay for retiree health care coverage for certain current and future retirees to 3% and to require retiree medical plan participants to begin purchasing individual coverage in the Affordable Insurance Exchanges or individual Medicare marketplace beginning January 1, 2016 using a company-funded subsidy based upon years of service at retirement. For the measurement of the APBO at December 31, 2015 for our Canadian postretirement health care plan, the assumed health care cost trend rates start with an 8% increase in 2016 , followed by a gradual decline in increases to 4% for 2032. For the measurement of the APBO at December 31, 2014 , the assumed health care cost trend rates started with a 8.25% increase in 2015 , followed by a gradual decline in increases to 4% for 2032 and beyond. A one percentage point change in the assumed health care cost trend rates would have the following effects on our U.S. and Canadian plans: (millions) One-Percentage- Point Increase One-Percentage- Point Decrease Effect on total service and interest cost $ 1 $ — Effect on postretirement benefit obligation 10 (8 ) RETIREMENT PLAN ASSETS Investment Policies and Strategies : We have established investment policies and strategies for the defined benefit pension plans’ assets with a long-term objective of maintaining the plans’ assets at a level equal to or greater than that of their liabilities (as measured by a funded ratio of 100% or more of the ABO) and maximizing returns on the plans’ assets consistent with our moderate tolerance for risk. Contributions are made to the plans periodically as needed to meet funding targets or requirements. Factors influencing our determination to accept a moderate degree of risk include the timing of plan participants’ retirements and the resulting disbursement of retirement benefits, the liquidity requirements of the plans and our financial condition. Our overall long-term objective is to achieve a 6.7% rate of return on plan assets with a moderate level of risk as indicated by the volatility of investment returns. This rate of return target was established using a “building block” approach. In this approach, ranges of long-term expected returns for the various asset classes in which the plans invest are estimated. The estimated ranges are primarily based on observations of historical asset returns and their historical volatility. In determining the expected returns, we also consider consensus forecasts of certain market and economic factors that influence returns, such as inflation, gross domestic product trends and dividend yields. We then calculate an overall range of likely expected rates of return by applying the expected asset returns to the plans’ target asset allocation. The most likely rate of return is then determined and is adjusted to account for investment management fees. Our investment strategy is to invest in a diversified mix of asset classes in accordance with an asset allocation that we believe is likely to achieve our long-term target return while prudently considering risk. In order to manage risk, the plans’ pension and investment committees periodically rebalance the asset allocations as outlined by our investment policy statements. Our investment policy statements include glide paths which outline how our asset allocation would increase the portion of liability-hedging assets, such as fixed income, as our funded status improves in the future. This liability-driven investing approach is carried out by professional investment managers who help the committees in this process. The committees also monitor the investment performance of the individual investment managers compared to their benchmark returns and investment guidelines on an ongoing basis, in part through the use of quarterly investment portfolio reviews and compliance reporting by investment managers. The pension and investment committees also evaluate risk by periodically conducting asset/liability studies to assess the correlation of the plans’ assets and liabilities and the degree of risk in the target asset allocations. The plans limit the use of leverage to select investment strategies where leverage is typically employed, such as private equity and real estate. Certain investment managers utilize derivatives, such as swaps, bond futures, and options, as part of their investment strategies. This is done primarily to gain a desired market exposure or manage factors such as interest rate risk or duration of a bond portfolio. The following table shows the aggregate target asset allocation on a weighted average basis for all the plans and the acceptable ranges around the targets as of December 31, 2015 . Investment Policy Target Range Asset Categories: Asset Category Description Equity Institutional commingled/pooled equity funds, equity mutual funds and direct holdings of the common stock of U.S. and non-U.S. companies; equity funds and direct holdings are invested in companies with a range of market capitalizations 40 % 36% - 42% Fixed income U.S. Treasury securities, non-U.S. government debt securities such as Canadian federal bonds, corporate bonds of companies from diversified industries and mortgage-backed securities 49 % 46% - 52% Limited partnerships Investments in funds that follow any of several different strategies, including investing in distressed debt, energy development, infrastructure, and hedge funds. These investments use strategies with returns normally expected to have a reduced correlation to the return of equities as compared to other asset classes and often provide a current income component that is a meaningful portion of the investment’s total return. 5 % 2% -8% Other real assets Primarily investments in large core, private real estate funds that directly own a diverse portfolio of properties located in the United States. It also includes an allocation to funds investing in equities of real estate and infrastructure companies 6 % 3% - 9% Cash equivalents and short-term investments Primarily held in short-term investment funds or registered money market funds with daily liquidity — % 0% - 5% Total 100 % Fair Values of Plan Assets : Pension assets are classified based on the valuation methodologies and inputs used to determine the fair value as described in Note 1. Level 1 investments include mutual funds, or direct investments in common stocks of U.S. and non-U.S. companies that trade on liquid exchanges. These investments are valued based on the closing price on these exchanges. Level 2 investments include primarily fixed income securities such as corporate, or government debentures, mortgage- and asset-backed securities. They are valued primarily using income and market approaches, such as pricing based on recent market transactions, and values are based on quoted prices or other observable market inputs received from data providers. Commingled funds not traded on an exchange, even though their underlying investments are common stocks traded on liquid exchanges, are also included in the Level 2 category. The net asset value of commingled funds investing in either stocks or fixed income securities is calculated by subtracting the value of any liabilities from the market value of all securities owned by a fund. Level 3 investments include real estate, infrastructure, or direct energy investments as well as distressed securities or hedge funds. These are valued using income approach methodologies such as discounted cash flows, or market approach methodologies such as relative value (specific to equity securities), direct capitalization and comparable sales (specific to real estate investments). Some of the key inputs used to value these securities include discount rate, EBITDA multiple, yield-to-worst, yield-to-maturity, and cap rate (specific to real estate investments). The fair values by hierarchy of inputs as of December 31 were as follows: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total (millions) 2015 2014 2015 2014 2015 2014 2015 2014 Asset Categories: Equity: (a) Common and preferred stock $ 55 $ 74 $ — $ — $ — $ — $ 55 $ 74 Commingled/pooled/mutual funds 54 53 448 470 — — 502 523 Total equity 109 127 448 470 — — 557 597 Fixed income: U.S. government and agency debt securities — — 177 195 — — 177 195 Non-U.S. government and agency debt securities — — 32 30 — — 32 30 Investment-grade debt securities — — 199 184 — — 199 184 High-yield debt securities — — 36 39 — — 36 39 Commingled/pooled funds — — 129 114 — — 129 114 Other — — 3 8 1 1 4 9 Total fixed income — — 576 570 1 1 577 571 Limited partnerships — — — — 106 103 106 103 Other real estate assets — — 15 20 37 35 52 55 Cash equivalents and short-term investments — — 10 17 — — 10 17 Total $ 109 $ 127 $ 1,049 $ 1,077 $ 144 $ 139 $ 1,302 $ 1,343 Cash on hand — — Receivables 9 1 Accounts payable (10 ) (4 ) Total $ 1,301 $ 1,340 (a) Certain investments in commingled/pooled equity funds have been classified as Level 2 in 2015 and 2014 because observable quoted prices for these institutional funds are not available. A reconciliation of the change in the fair value measurement of the defined benefit plans’ consolidated assets using significant unobservable inputs (Level 3) between January 1, 2014 and December 31, 2015 is as follows: (millions) Fixed Income Other Real Estate Assets Limited Partnerships Total Balance as of January 1, 2014 $ 1 $ 35 $ 39 $ 75 Realized gains — 1 — 1 Unrealized gains (losses) — 1 (2 ) (1 ) Purchases, sales and settlements: Purchases — — 67 67 Sales — (2 ) (1 ) (3 ) Settlements — — — — Net transfers into (out of) Level 3 — — — — Balance as of December 31, 2014 $ 1 $ 35 $ 103 $ 139 Realized losses — (1 ) — (1 ) Unrealized gains — 5 1 6 Purchases, sales and settlements: Purchases — — 2 2 Sales — (2 ) — (2 ) Settlements — — — — Net transfers into (out of) Level 3 — — — — Balance as of December 31, 2015 $ 1 $ 37 $ 106 $ 144 CASH FLOWS For 2016 , our defined benefit pension plans have no minimum funding requirements under the Employee Retirement Income Security Act of 1974. We are evaluating our level of funding for pension plans and currently estimate that we will contribute approximately $65 million to our pension plans in 2016 . Our cash payments for postretirement plans are estimated to be $9 million in 2016 . Total benefit payments we expect to make to participants, which include payments funded from USG’s assets as well as payments from our pension plans' assets, are as follows (in millions): Years ended December 31 Pension Benefits Postretirement Benefits 2016 $ 105 $ 9 2017 84 9 2018 94 10 2019 95 10 2020 128 8 2021 - 2025 585 43 DEFINED CONTRIBUTION PLANS Total charges for our defined contribution plans amounted to approximately $7 million , $6 million and $3 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. These charges primarily consisted of contributions to our U.S. plan, commonly known as a 401(k) plan. The U.S. plan provides participating employees the opportunity to invest 1% to 75% of their compensation on a pretax and/or Roth after-tax basis. Effective January 1, 2014, participants earn a guaranteed company match of 25% on employee contributions up to 6% of their eligible compensation. During 2013 the company match was 10% on contributions up to 6% of their eligible compensation. Employees are fully vested in company matching contributions after three years of participation in the plan. USG’s contributions are charged to cost of products sold and selling and administrative expenses.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	Share-Based Compensation We grant share-based compensation to eligible participants under our Long-Term Incentive Plan, or LTIP. The LTIP was approved by our Board of Directors and stockholders. As of December 31, 2015 , a total of 12.7 million shares of common stock were authorized for grants under the LTIP, of which 3 million shares were reserved for future grants. The LTIP authorizes the Board, or the Board’s Compensation and Organization Committee, to provide equity-based compensation in the form of stock options, stock appreciation rights, or SARs, restricted stock, restricted stock units, or RSUs, market share units, or MSUs, performance shares and units, and other cash and share-based awards for the purpose of providing our non-employee directors, officers and other employees incentives and rewards for performance. We may issue common shares upon option exercises and upon the vesting or grant of other awards under the LTIP from our authorized but unissued shares or from treasury shares. Our expense for share-based arrangements was $15 million in 2015 , $ 21 million in 2014 and $ 19 million in 2013 and is included in selling and administrative expense in our consolidated statements of operations. No income tax benefits were recognized for share-based arrangements in the consolidated statements of operations in 2015 , 2014 and 2013 . We recognize expense on all share-based awards over the service period, which is the shorter of the period until the employees’ retirement eligibility dates or the service period of the award for awards expected to vest. For awards with graded vesting that only contain a service condition, we recognize expense on a straight-line basis over the service period. Expense is generally reduced for estimated forfeitures. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. Excess tax benefits related to share based compensation are the difference between the amount of deductible compensation expense reported for tax purposes and the compensation expense recorded for financial reporting purposes for a stock award. Excess tax benefits that are not realized are not reflected in additional paid-in-capital until there is a reduction to taxes payable. As a result of the NOL carryforwards for federal tax purposes in 2015 , 2014 and 2013 , none of the excess tax benefits with respect to exercised stock options and vestings of RSUs, MSUs and performance shares for those years has been reflected in additional paid-in-capital as of December 31, 2015 . Included in our federal tax NOL carryforwards is $68 million of unrealized excess tax benefits for which a tax benefit of $24 million will be recorded in additional paid-in-capital if the loss carryforward is fully utilized. STOCK OPTIONS We last granted stock options in 2012. Stock options generally become exercisable in four equal annual installments beginning one year from the date of grant, although they may become exercisable earlier in the event of death, disability, retirement or a change in control. The stock options generally expire ten years from the date of grant, or earlier in the event of death, disability or retirement. A summary of stock options outstanding as of December 31, 2015 and of stock option activity during 2015 is presented below: Number of Options (000) Weighted Average Exercise Price Weighted Average Remaining Contractual Term (years) Aggregate Intrinsic Value (millions) Outstanding at January 1, 2015 3,982 $ 26.77 4.17 $ 31 Exercised (410 ) 14.61 Canceled (67 ) 41.50 Forfeited (9 ) 14.76 Outstanding at December 31, 2015 3,496 $ 28.00 3.06 $ 19 Exercisable at December 31, 2015 3,363 $ 28.51 2.93 $ 18 Vested or expected to vest at December 31, 2015 3,496 $ 28.00 2.99 $ 19 Intrinsic value for stock options is defined as the difference between the current market value of our common stock and the exercise price of the stock options. The total intrinsic value of stock options exercised was $6 million in 2015 , $8 million in 2014 and $7 million in 2013 and cash received from the exercise of stock options was $6 million in 2015 , $4 million in 2014 and $4 million in 2013 . The total fair value of stock options vested was $1 million during 2015 , $2 million during 2014 and $10 million during 2013 . MARKET SHARE UNITS We granted market share units, or MSUs, during 2015 , 2014 , and 2013 with weighted average grant date fair values of $30.06 , $40.20 , and $34.55 , respectively. MSUs generally vest after a three -year period based on our actual stock price performance during such period. The number of MSUs earned will vary from zero to 150% of the number of MSUs awarded depending on the actual performance of our stock price. In the case of termination of employment due to death, disability or retirement during the performance period, vesting will be pro-rated based on the number of full months employed in 2015 . Awards earned will be issued at the end of the three -year period. MSUs may vest earlier in the case of a change in control in most circumstances only if there is also a related loss of employment or diminution of duties. Each MSU earned will be settled in common stock. We estimated the fair value of each MSU granted on the date of grant using a Monte Carlo simulation that used the assumptions noted in the following table. Volatility was based on stock price history immediately prior to grant for a period commensurate with the expected term. The risk-free rate was based on zero-coupon U.S. government issues at the time of grant. The expected term represents the period from the valuation date to the end of the performance period. Assumptions: 2015 2014 2013 Expected volatility 42.70 % 54.93 % 60.97 % Risk-free rate 1.09 % 0.63 % 0.35 % Expected term (in years) 2.95 2.94 2.38 Expected dividends — — — Nonvested MSUs outstanding as of December 31, 2015 and MSU activity during 2015 were as follows: Weighted Number of Shares (000) Weighted Average Grant Date Fair Value Nonvested at January 1, 2015 511 $ 38.43 Granted 474 30.06 Vested (156 ) 34.80 Forfeited (86 ) 34.34 Nonvested at December 31, 2015 743 34.33 Half of the MSUs granted in 2013 vested after a three -year performance period ended December 31, 2015 . Of those MSUs granted with a three -year performance period, 155,595 vested for approximately 119,808 common shares based on the actual performance of our stock price. The remaining MSUs with a three -year performance period granted in 2013 were forfeited. Total unrecognized compensation cost related to nonvested share-based compensation awards represented by MSUs granted under the LTIP was $ 4 million as of December 31, 2015 . We expect that cost to be recognized over a weighted average period of 1.7 years . RESTRICTED STOCK UNITS We granted RSUs during 2015 , 2014 and 2013 with weighted average grant date fair values of $28.56 , $32.50 and $29.44 , respectively. RSUs granted as special retention awards, including those granted in 2015, generally vest after a specified number of years from the date of grant or at a specified date and RSUs granted with performance goals vest if those goals are attained. RSUs may vest earlier in the case of death, disability, retirement or a change in control. Each RSU is settled in a share of our common stock after the vesting period. The fair value of each RSU granted is equal to the closing market price of our common stock on the date of grant. In 2015 , we granted RSUs as special retention awards with respect to 94,000 shares of common stock that generally vest in three years from the date of grant. RSUs outstanding as of December 31, 2015 and RSU activity during 2015 were as follows: Number of Shares (000) Weighted Average Grant Date Fair Value Nonvested at January 1, 2015 423 $ 20.12 Granted 94 28.56 Vested (220 ) 17.84 Forfeited (27 ) 24.36 Nonvested at December 31, 2015 270 24.49 As of December 31, 2015 , there was $3 million of total unrecognized compensation cost related to nonvested share-based compensation awards represented by RSUs granted under the LTIP. We expect that cost to be recognized over a weighted average period of 2.6 years . The total fair value of RSUs that vested was $4 million during 2015 , $ 6 million during 2014 and $ 7 million during 2013 . PERFORMANCE SHARES We granted performance shares during 2015 , 2014 and 2013 . The weighted average grant date fair value was $30.63 for 2015 , $46.46 in 2014 , and $38.89 in 2013 . The performance shares generally vest after a period of three years based on our total stockholder return relative to the performance of the Dow Jones U.S. Construction and Materials Index, with adjustments to that index in certain circumstances, for the three-year period. The number of performance shares earned will vary from zero to 200% of the number of performance shares awarded depending on that relative performance. Vesting will be pro-rated based on the number of full months employed during the performance period in the case of death, disability, retirement or a change in control, and pro-rated awards earned will be settled in common stock at the end of the three -year period. We estimated the fair value of each performance share granted on the date of grant using a Monte Carlo simulation that uses the assumptions noted in the following table. Volatility was based on stock price history immediately prior to grant for a period commensurate with the expected term. The risk-free rate was based on zero coupon U.S. government issues at the time of grant. The expected term represents the period from the grant date to the end of the three -year performance period. Assumptions: 2015 2014 2013 Expected volatility 42.70 % 54.93 % 59.98 % Risk-free rate 1.09 % 0.63 % 0.43 % Expected term (in years) 2.95 2.94 2.88 Expected dividends — — — Nonvested performance shares outstanding as of December 31, 2015 and performance share activity during 2015 were as follows: Weighted Number of Shares (000) Weighted Average Grant Date Fair Value Nonvested at January 1, 2015 203 $ 42.82 Granted 147 30.63 Vested (89 ) 38.89 Forfeited (39 ) 24.12 Nonvested at December 31, 2015 222 37.20 With respect to the performance shares granted in 2013 , for which the three -year performance period ended December 31, 2015 , 89,040 of the performance shares vested for no common shares. The remaining performance shares with a three -year performance period granted in 2013 were forfeited. Total unrecognized compensation cost related to nonvested share-based compensation awards represented by performance shares granted under the LTIP was $4 million as of December 31, 2015 . We expect that cost to be recognized over a weighted average period of 1.7 years . NON-EMPLOYEE DIRECTOR DEFERRED STOCK UNITS Our non-employee directors may elect to receive a portion of their compensation as deferred stock units that increase or decrease in value in direct relation to the market price of our common stock. Deferred stock units earned through December 31, 2007 will be paid in cash upon termination of board service. Deferred stock units earned thereafter will be paid in cash or shares of USG common stock, at the election of the director, upon termination of board service. The number of deferred stock units held by non-employee directors was approximately 193,117 as of December 31, 2015 , 164,235 as of December 31, 2014 and 182,632 as of December 31, 2013 . We recorded expense related to these deferred stock units of $1 million in 2015 , 2014 and 2013 , respectively.

Supplemental Balance Sheet Info

Supplemental Balance Sheet Information	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Supplemental Balance Sheet Information	Supplemental Balance Sheet Information INVENTORIES Inventories as of December 31 consisted of the following: (millions) 2015 2014 Finished goods $ 210 $ 232 Work in progress 36 35 Raw materials 68 62 Total $ 314 $ 329 PROPERTY, PLANT AND EQUIPMENT Property, plant and equipment as of December 31 consisted of the following: (millions) 2015 2014 Land and mineral deposits $ 131 $ 135 Buildings and improvements 1,088 1,095 Machinery and equipment 2,505 2,563 3,724 3,793 Reserves for depreciation and depletion (1,936 ) (1,885 ) Total $ 1,788 $ 1,908 Annual depreciation and depletion expense $ 130 $ 134 ACCRUED EXPENSES Accrued expenses as of December 31 consisted of the following: (millions) 2015 2014 Self-insurance reserves $ 20 $ 21 Employee compensation 40 42 Interest 45 45 Restructuring — 1 Derivatives 17 18 Pension and other postretirement benefits 18 22 Environmental 16 16 Other 58 55 Total $ 214 $ 220 ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) Changes in the balances of each component of accumulated other comprehensive income (loss), or AOCI, are summarized in the following table: (millions) Derivatives Pension and Other Postretirement Benefit Plans Foreign Total AOCI Balance as of January 1, 2013 $ 32 $ (303 ) $ 38 $ (233 ) Other comprehensive income (loss) before reclassifications 4 247 (17 ) 234 Less: Amounts reclassified from AOCI, net of tax 1 (24 ) — (23 ) Other comprehensive income (loss), net of tax 3 271 (17 ) 257 Balance as of December 31, 2013 $ 35 $ (32 ) $ 21 $ 24 Other comprehensive loss before reclassifications (15 ) (272 ) (68 ) (355 ) Less: Amounts reclassified from AOCI, net of tax 4 (2 ) 5 7 Other comprehensive loss, net of tax (19 ) (270 ) (73 ) (362 ) Balance as of December 31, 2014 $ 16 $ (302 ) $ (52 ) $ (338 ) Other comprehensive (loss) income before reclassifications (5 ) 74 (67 ) 2 Less: Amounts reclassified from AOCI, net of tax (9 ) (7 ) (6 ) (22 ) Other comprehensive income (loss), net of tax 4 81 (61 ) 24 Balance as of December 31, 2015 $ 20 $ (221 ) $ (113 ) $ (314 ) Amounts reclassified from AOCI, net of tax, for the years ended December 31, 2015 and 2014 , were as follows: (millions) 2015 2014 Derivatives Net reclassification from AOCI for cash flow hedges included in cost of products sold $ (8 ) $ 4 Net reclassification from ACOI for cash flow hedges included in income and gain from the sale of equity method investment to related party 1 — Less: Income tax expense on reclassification from AOCI included in income tax expense 2 — Net amount reclassified from AOCI $ (9 ) $ 4 Pension and postretirement benefits Net reclassification from AOCI for amortization of prior service (benefit) cost included in cost of products sold $ (5 ) $ 7 Net reclassification from AOCI for amortization of prior service (benefit) cost included in selling and administrative expenses (3 ) (10 ) Less: Income tax expense on reclassification from AOCI included in income tax expense (benefit) (1 ) (1 ) Net amount reclassified from AOCI $ (7 ) $ (2 ) Foreign Currency Translation Net reclassification from AOCI for translation (loss) gain realized upon the sale of foreign entities $ (6 ) $ 5 Less: Income tax expense on reclassification from AOCI included in income tax expense (benefit) — — Net amount reclassified from AOCI $ (6 ) $ 5 We estimate that we will reclassify a net $9 million after-tax loss on derivatives from AOCI to earnings within the next 12 months. ASSET RETIREMENT OBLIGATIONS Changes in our liability for asset retirement obligations during 2015 and 2014 consisted of the following: (millions) 2015 2014 Balance as of January 1 $ 123 $ 132 Accretion expense 7 7 Liabilities incurred 1 2 Changes in estimated cash flows (a) (5 ) (13 ) Liabilities settled (2 ) (2 ) Foreign currency translation (5 ) (3 ) Balance as of December 31 $ 119 $ 123 (a) Changes in estimated cash flows for the year ended December 31, 2014 includes changes in estimates primarily for our gypsum quarry and ship loading facility in Windsor, Nova Scotia, Canada, which we permanently closed during the third quarter of 2011, and our mining operation in Little Narrows, Nova Scotia, Canada as a result of receiving regulatory approval of a revised reclamation plan in 2014. Our asset retirement obligations include reclamation requirements as regulated by government authorities related principally to assets such as our mines, quarries, landfills, ponds and wells. The accounting for asset retirement obligations requires estimates by management about the timing of asset retirements, the cost of retirement obligations, discount and inflation rates used in determining fair values and the methods of remediation associated with our asset retirement obligations. We generally use assumptions and estimates that reflect the most likely remediation method on a site-by-site basis. Our estimated liability for asset retirement obligations is revised annually, and whenever events or changes in circumstances indicate that a revision to the estimate is necessary. In instances where a decrease in the asset retirement obligation is in excess of the related remaining net book value of the asset retirement costs, the excess is recorded to the consolidated statement of operations as a reduction in cost of products sold. Asset retirement obligations are included in other liabilities on the consolidated balance sheets.

Long-Lived Asset Impairment Cha

Long-Lived Asset Impairment Charges	12 Months Ended
	Dec. 31, 2015
Restructuring and Related Activities [Abstract]
Long-Lived Asset Impairment Charges	Long-Lived Asset Impairment Charges We continuously evaluate our manufacturing needs by considering the capacity of existing and idled plants and production lines, as well as capital projects for manufacturing facilities, relative to the demand assumptions included in our long-range plan. Although industry and economic factors have improved and we believe that the overall economic recovery is intact, they are improving at a slower pace than expected, which required us to reconsider the future utilization of idled plants and production lines, and capital projects for manufacturing facilities. In 2014, we recorded the following impairment charges: (millions) 2014 Ocean vessels $ 60 Wallboard lines or facilities 16 Previously incurred costs related to construction of future facilities 12 Other 2 Total long-lived asset impairment charges $ 90 There were no impairment charges recorded in 2015 or 2013. In 2014, the long-lived asset impairment charges totaling $90 million included the following: (a) $60 million related to two self-unloading ocean vessels that were subsequently sold in the second quarter of 2015. See Note 13 for further discussion. (b) $16 million related to the carrying values of machinery, equipment and buildings at our temporarily idled gypsum quarry and wallboard production facility in Empire, Nevada and at our previously idled and now permanently closed gypsum wallboard line in New Orleans, Louisiana. In addition, in the third quarter of 2014 we permanently closed our wallboard line in Detroit, Michigan. No impairment charge was recorded with respect to our wallboard line in Detroit, Michigan, as these assets were previously impaired at the time the plant was originally idled. (c) $12 million related to previously incurred and capitalized costs for the construction of two future facilities which we do not anticipate will be built within our planning horizon. (d) $2 million related to the carrying values of machinery, equipment and buildings at our previously idled and now permanently closed paper production line in Gypsum, Ohio. The carrying values of the machinery, equipment and buildings at our temporarily idled facility in Empire, Nevada exceeded the estimated future undiscounted cash flows for the remaining useful lives of the assets due to slower than expected acceleration in the markets served by this facility and our forecasts regarding the timing and future rate of recovery in those markets. Based on these conditions, we do not anticipate that the carrying values of the assets at this facility would be recovered prior to end of the assets’ useful lives, and therefore fully impaired these assets. For the production line in Gypsum, Ohio that we deemed to be permanently closed, we fully impaired the long-lived assets specific to that line. The long-lived asset impairment charges relate solely to our Gypsum segment. Gypsum Transportation Limited Gypsum Transportation Limited, or GTL, owned two self-unloading ocean vessels. The two previously owned vessels and the third previously leased vessel were used to transship iron ore in and around Sierra Leone in accordance with a contract of affreightment. During 2014, our trading partner ceased performing under the contract, and consequently, we terminated the agreement. As a result of the contract termination, we assessed the recoverability of the two owned vessels and recorded an impairment charge of $60 million . Also in 2014, we recorded a contract termination charge of $6 million for costs to be incurred for the remaining term without economic benefit to us under the lease of the third vessel and we recorded a $9 million provision for bad debt for the trade receivable from our trading partner that we deemed uncollectible. The impairment charge for the two owned vessels is recorded within "Long-lived asset impairment charges" on our consolidated statement of operations. The contract termination charge and provision for bad debt are recorded within "Contract termination and (recovery) loss on receivable" on our consolidated statements of operations. In April 2015, we completed the sale of our two self-unloading ocean vessels owned by GTL for $42 million and recorded a gain of $7 million on the disposition. With a portion of the proceeds from the sale, GTL repaid the outstanding loan balance under GTL’s secured loan facility agreement with DVB Bank SE and paid applicable selling costs. Additionally, we returned the third vessel leased by GTL and paid $7 million of early termination costs which were previously accrued for in 2014. In the second quarter of 2015, GTL incurred charges of $6 million to exit our shipping operations. The net impact of the gain on the sale of the vessels and charges incurred to exit the shipping operations of $1 million is recorded in “Gain on disposal of shipping operations, net” on the consolidated statement of operations. In November 2015, we entered into a release and debt settlement agreement (Settlement Agreement) to recover a portion of our loss incurred when our former trading partner ceased performing under the contract in the fourth quarter of 2014. The Settlement Agreement requires payments beginning in December 2015 for a total of $14 million . For the payments received that are meant to settle the $9 million loss on the trade receivable, we will record the benefit to our statement of operations when we determine the payments to be probable. For the remaining $5 million we will record the benefit to the statement of operations when realization is assured beyond a reasonable doubt, which is generally when the payments are received. For the year ended December 31, 2015 , we have recorded a recovery of $6 million and it is presented within the "Contract termination and (recovery) loss on receivable" on our consolidated statement of operations. GTL recorded operating profit (loss) of $7 million in 2015 , ($52) million in 2014 , and $20 million in 2013 .

Gypsum Transportation Limited

Gypsum Transportation Limited	12 Months Ended
	Dec. 31, 2015
Restructuring and Related Activities [Abstract]
Gypsum Transportation Limited	Long-Lived Asset Impairment Charges We continuously evaluate our manufacturing needs by considering the capacity of existing and idled plants and production lines, as well as capital projects for manufacturing facilities, relative to the demand assumptions included in our long-range plan. Although industry and economic factors have improved and we believe that the overall economic recovery is intact, they are improving at a slower pace than expected, which required us to reconsider the future utilization of idled plants and production lines, and capital projects for manufacturing facilities. In 2014, we recorded the following impairment charges: (millions) 2014 Ocean vessels $ 60 Wallboard lines or facilities 16 Previously incurred costs related to construction of future facilities 12 Other 2 Total long-lived asset impairment charges $ 90 There were no impairment charges recorded in 2015 or 2013. In 2014, the long-lived asset impairment charges totaling $90 million included the following: (a) $60 million related to two self-unloading ocean vessels that were subsequently sold in the second quarter of 2015. See Note 13 for further discussion. (b) $16 million related to the carrying values of machinery, equipment and buildings at our temporarily idled gypsum quarry and wallboard production facility in Empire, Nevada and at our previously idled and now permanently closed gypsum wallboard line in New Orleans, Louisiana. In addition, in the third quarter of 2014 we permanently closed our wallboard line in Detroit, Michigan. No impairment charge was recorded with respect to our wallboard line in Detroit, Michigan, as these assets were previously impaired at the time the plant was originally idled. (c) $12 million related to previously incurred and capitalized costs for the construction of two future facilities which we do not anticipate will be built within our planning horizon. (d) $2 million related to the carrying values of machinery, equipment and buildings at our previously idled and now permanently closed paper production line in Gypsum, Ohio. The carrying values of the machinery, equipment and buildings at our temporarily idled facility in Empire, Nevada exceeded the estimated future undiscounted cash flows for the remaining useful lives of the assets due to slower than expected acceleration in the markets served by this facility and our forecasts regarding the timing and future rate of recovery in those markets. Based on these conditions, we do not anticipate that the carrying values of the assets at this facility would be recovered prior to end of the assets’ useful lives, and therefore fully impaired these assets. For the production line in Gypsum, Ohio that we deemed to be permanently closed, we fully impaired the long-lived assets specific to that line. The long-lived asset impairment charges relate solely to our Gypsum segment. Gypsum Transportation Limited Gypsum Transportation Limited, or GTL, owned two self-unloading ocean vessels. The two previously owned vessels and the third previously leased vessel were used to transship iron ore in and around Sierra Leone in accordance with a contract of affreightment. During 2014, our trading partner ceased performing under the contract, and consequently, we terminated the agreement. As a result of the contract termination, we assessed the recoverability of the two owned vessels and recorded an impairment charge of $60 million . Also in 2014, we recorded a contract termination charge of $6 million for costs to be incurred for the remaining term without economic benefit to us under the lease of the third vessel and we recorded a $9 million provision for bad debt for the trade receivable from our trading partner that we deemed uncollectible. The impairment charge for the two owned vessels is recorded within "Long-lived asset impairment charges" on our consolidated statement of operations. The contract termination charge and provision for bad debt are recorded within "Contract termination and (recovery) loss on receivable" on our consolidated statements of operations. In April 2015, we completed the sale of our two self-unloading ocean vessels owned by GTL for $42 million and recorded a gain of $7 million on the disposition. With a portion of the proceeds from the sale, GTL repaid the outstanding loan balance under GTL’s secured loan facility agreement with DVB Bank SE and paid applicable selling costs. Additionally, we returned the third vessel leased by GTL and paid $7 million of early termination costs which were previously accrued for in 2014. In the second quarter of 2015, GTL incurred charges of $6 million to exit our shipping operations. The net impact of the gain on the sale of the vessels and charges incurred to exit the shipping operations of $1 million is recorded in “Gain on disposal of shipping operations, net” on the consolidated statement of operations. In November 2015, we entered into a release and debt settlement agreement (Settlement Agreement) to recover a portion of our loss incurred when our former trading partner ceased performing under the contract in the fourth quarter of 2014. The Settlement Agreement requires payments beginning in December 2015 for a total of $14 million . For the payments received that are meant to settle the $9 million loss on the trade receivable, we will record the benefit to our statement of operations when we determine the payments to be probable. For the remaining $5 million we will record the benefit to the statement of operations when realization is assured beyond a reasonable doubt, which is generally when the payments are received. For the year ended December 31, 2015 , we have recorded a recovery of $6 million and it is presented within the "Contract termination and (recovery) loss on receivable" on our consolidated statement of operations. GTL recorded operating profit (loss) of $7 million in 2015 , ($52) million in 2014 , and $20 million in 2013 .

Segments

Segments	12 Months Ended
	Dec. 31, 2015
Segment Reporting [Abstract]
Segments	Segments Our operations are organized into four reportable segments: Gypsum, Ceilings, Distribution and USG Boral Building Products, or UBBP. Segment results were as follows: GYPSUM, CEILINGS AND DISTRIBUTION For the year ended December 31, (millions) 2015 2014 2013 Net Sales: Gypsum $ 2,397 $ 2,403 $ 2,262 Ceilings 499 513 568 Distribution 1,428 1,345 1,245 Eliminations (548 ) (537 ) (505 ) Total $ 3,776 $ 3,724 $ 3,570 Operating Profit (Loss): Gypsum $ 348 $ 169 $ 261 Ceilings 89 87 98 Distribution 27 16 6 Corporate (95 ) (109 ) (93 ) Eliminations 12 (1 ) (14 ) Total $ 381 $ 162 $ 258 Depreciation, Depletion and Amortization: Gypsum $ 106 $ 116 $ 115 Ceilings 16 14 14 Distribution 11 12 12 Corporate 9 12 14 Total $ 142 $ 154 $ 155 Capital Expenditures: Gypsum $ 86 $ 96 $ 66 Ceilings 3 30 54 Distribution 5 5 3 Corporate — 1 1 Total $ 94 $ 132 $ 124 Assets: December 31, 2015 December 31, 2014 Gypsum $ 1,991 $ 2,106 Ceilings 276 285 Distribution 376 412 Corporate 1,487 489 Equity method investments 682 735 Eliminations (76 ) (91 ) Total $ 4,736 $ 3,936 GEOGRAPHIC INFORMATION For the year ended December 31, (millions) 2015 2014 2013 Net Sales: United States $ 3,387 $ 3,220 $ 3,029 Canada 379 406 417 Other Foreign 196 283 309 Geographic transfers (186 ) (185 ) (185 ) Total $ 3,776 $ 3,724 $ 3,570 Long-lived assets, consisting of property, plant and equipment, net, by geographic location were as follows: (millions) December 31, December 31, Long-Lived Assets: United States $ 1,622 $ 1,665 Canada 90 112 Other Foreign 76 131 Total $ 1,788 $ 1,908 UBBP For the year ended December 31, (millions) 2015 2014 (a) Net sales $ 1,003 $ 927 Operating profit 124 95 Net income attributable to UBBP 96 67 Depreciation, depletion, and amortization 43 31 Capital expenditures 49 40 December 31, 2015 December 31, 2014 Assets $ 1,303 $ 1,435 UBBP GEOGRAPHIC INFORMATION For the year ended December 31, (millions) 2015 2014 (a) Net Sales: Australia $ 345 $ 312 South Korea 200 197 China 120 122 Thailand 145 133 Other 234 206 Geographic Transfers (41 ) (43 ) Total $ 1,003 $ 927 (a) Operating results are presented for UBBP for the ten months ended December 31, 2014 . Long-lived assets, consisting of property, plant and equipment, net, by geographic location for UBBP were as follows: (millions) December 31, 2015 December 31, 2014 Long-Lived Assets: Australia $ 216 $ 245 South Korea 106 113 China 116 127 Oman 103 96 Thailand 72 72 Other 67 78 Total $ 680 $ 731 OTHER SEGMENT INFORMATION Segment operating profit (loss) includes all costs and expenses directly related to the segment involved and an allocation of expenses that benefit more than one segment. Revenues are attributed to geographic areas based on the location of the assets producing the revenues. Transactions between reportable segments and geographic areas are accounted for at transfer prices that are approximately equal to market value. Intercompany transfers between segments (shown above as eliminations) largely reflect intercompany sales from U.S. Gypsum to L&W Supply. Geographic transfers largely reflect intercompany sales from U.S. Gypsum and USG Interiors, LLC to CGC and USG Mexico, S.A. de C.V. The Home Depot, Inc. accounted for approximately 16% of our consolidated net sales in both 2015 and 2014 and approximately 15% of our sales in 2013 . Our Gypsum, Ceilings and Distribution segments had net sales to The Home Depot, Inc. in each of those years.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income from continuing operations before income taxes consisted of the following: (millions) 2015 2014 2013 U.S. $ 178 $ 27 $ 17 Foreign 84 19 42 Total $ 262 $ 46 $ 59 Income tax expense (benefit) on continuing operations consisted of the following: (millions) 2015 2014 2013 Current: Federal $ — $ — $ — Foreign 12 2 10 State 1 1 1 13 3 11 Deferred: Federal (621 ) — (2 ) Foreign (4 ) 4 2 State (117 ) — — (742 ) 4 — Total $ (729 ) $ 7 $ 11 For our continuing operations, differences between actual provisions for income taxes and provisions for income taxes at the U.S. federal statutory rate ( 35% ) were as follows: (millions) 2015 2014 2013 Taxes on income from continuing operations at U.S. federal statutory rate $ 92 $ 16 $ 21 Foreign earnings subject to different tax rates (a) (3 ) 16 (6 ) State income tax, net of federal benefit 9 1 1 Change in valuation allowance (827 ) (9 ) (8 ) Income from equity method investments (b) (16 ) (12 ) — Withholding taxes — 2 6 Other, net 2 (1 ) (3 ) Tax release from AOCI — (2 ) — Gain on deconsolidation — (7 ) — Benefits from unrecognized tax positions (6 ) — — Tax benefit not realized on pension loss — 3 — Tax on distribution of foreign earnings 20 — — Provision for income tax expense $ (729 ) $ 7 $ 11 Effective income tax rate (277.7 )% 15.3 % 18.6 % (a) Foreign earnings subject to different tax rates includes amounts related to impairments and other charges associated with our GTL business. (b) Included in income from equity method investments are taxes associated with that income. These taxes, which are predominately foreign statutory rates, are at rates that are lower than the U.S. federal statutory rate. Significant components of deferred tax assets and liabilities as of December 31 were as follows: (millions) 2015 2014 Deferred Tax Assets: Net operating loss and tax credit carryforwards $ 779 $ 944 Pension and postretirement benefits 150 196 Goodwill and other intangible assets 24 29 Reserves not deductible until paid 29 47 Self insurance 11 15 Capitalized interest 13 15 Inventories 8 8 Share-based compensation 33 37 Other 5 11 Deferred tax assets before valuation allowance 1,052 1,302 Valuation allowance (75 ) (1,023 ) Total deferred tax assets $ 977 $ 279 Deferred Tax Liabilities: Property, plant and equipment 254 278 Other — — Total deferred tax liabilities 254 278 Net deferred tax assets $ 723 $ 1 A reduction of the carrying amounts of deferred tax assets by a valuation allowance is required if, based on all available evidence, it is more likely than not that such assets will not be realized. The need to establish valuation allowances for deferred tax assets is assessed at each reporting period. In assessing the requirement for, and amount of, a valuation allowance in accordance with the more-likely-than-not standard, we give appropriate consideration to all positive and negative evidence related to the realization of the deferred tax assets. This assessment considers, among other matters, the nature, frequency and severity of current and cumulative losses, forecasts of future profitability, the duration of statutory carryforward periods, our experience with operating loss and tax credit carryforwards not expiring unused and tax planning strategies. A history of cumulative losses for a certain threshold period is a significant form of negative evidence used in the assessment, and we are required to have a policy regarding the duration of the threshold period. We have a policy of four years as our threshold period for cumulative losses. In determining the need for the valuation allowance, we considered all positive and negative evidence. We give more weight to evidence that is objective in nature as compared to subjective evidence. Significant weight is given to evidence that directly relates to our current financial performance. As of December 31, 2015 , we emerged from a four-year cumulative pre-tax loss. In addition to meeting this threshold, there have been five consecutive quarters of domestic pre-tax earnings amounting to $194 million . The recent domestic pre-tax operating earnings is a significant, principal piece of positive evidence, which was weighed with the underlying momentum in the business, and generally improved market and economic conditions. Other evidence included strategic actions taken by management to lower costs and our expected utilization of deferred tax assets. All of this positive evidence lead to the determination that December 31, 2015 is the appropriate time to reverse a significant portion of the valuation allowance. During the current year, we recorded a decrease in the valuation allowance against our deferred tax assets of $948 million as of December 31, 2015. Of this decrease, $731 million was related to our evaluation for the need for a valuation allowance against our deferred tax assets and determination that it was more likely than not that most of our deferred tax assets would be realized. In addition, the remaining $217 million decrease included the decrease in the underlying deferred tax assets based upon current earnings and the use of NOL carryforwards offsetting those earnings, the planned repatriation of undistributed foreign earnings for our shipping operations and equity method investment in the Knauf-USG joint venture, the expiration of certain deferred tax assets, the decrease in our deferred tax assets for postretirement liabilities due to changes in AOCI and changes in the federal impact of our state deferred tax assets. As of December 31, 2015, our deferred tax assets of $723 million were offset by a valuation allowance of $75 million , consisting of $74 million for state deferred tax assets and $1 million for foreign deferred tax assets. The components of the valuation allowance remaining primarily relate to certain state Net Operating Loss (“NOL”) carryforwards that we anticipate will not be used prior to their expiration. As of December 31, 2015 , we had federal NOL carryforwards of approximately $1.755 billion that are available to offset future federal taxable income and will expire in the years 2026 through 2032 . In addition, as of that date, we had federal alternative minimum tax credit carryforwards of approximately $40 million that are available to reduce future regular federal income taxes over an indefinite period. In order to fully realize the U.S. federal net deferred tax assets, taxable income of approximately $1.870 billion would need to be generated during the period before their expiration. As of December 31, 2015 , we had a gross deferred tax asset of $230 million related to state NOLs and tax credit carryforwards, of which $27 million will expire in 2016 . The remainder will expire if unused in years 2017 through 2035 . To the extent that we do not generate sufficient state taxable income within the statutory carryforward periods to utilize the NOL and tax credit carryforwards in these states, they will expire unused. See previous discussion above on the valuation allowance. We also had NOL and tax credit carryforwards in various foreign jurisdictions in the amount of $1 million as of December 31, 2015 , against which we have maintained a valuation allowance. The Internal Revenue Code imposes limitations on a corporation’s ability to utilize NOLs if it experiences an “ownership change” which can result from transactions increasing the ownership of certain stockholders in the stock of a corporation by more than 50 percentage points over a three -year period. If we were to experience an ownership change, utilization of our NOLs would be subject to an annual limitation that may be carried over to later years within the allowed NOL carryforward period. Over the entire carryforward period, we may not be able to use all our NOLs due to the aforementioned annual limitation. If an ownership change had occurred as of December 31, 2015 , our annual U.S. federal NOL utilization would have been limited to approximately $92 million per year. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: (millions) 2015 2014 2013 Balance as of January 1 $ 22 $ 22 $ 16 Tax positions related to the current period: Gross increase 4 2 4 Gross decrease — — — Tax positions related to prior periods: Gross increase — — 2 Gross decrease (1 ) — — Settlements (6 ) (2 ) — Lapse of statutes of limitations (1 ) — — Balance as of December 31 $ 18 $ 22 $ 22 We classify interest expense and penalties related to unrecognized tax benefits and interest income on tax overpayments as components of income taxes (benefit). The total amounts of interest expense and penalties recognized on our consolidated balance sheets were $1 million and $3 million , respectively, as of December 31, 2015 and 2014. The total amounts of interest and penalties recognized in our consolidated statements of operations was zero in 2015 , zero for 2014 and zero for 2013 . The total amounts of unrecognized tax benefit that, if recognized, would affect our effective tax rate were $17 million for 2015 , $5 million for 2014 and $7 million for 2013 . Our federal income tax returns for 2008 and prior years have been examined by the Internal Revenue Service. The U.S. federal statute of limitations remains open for 2006 and later years. We are under examination in various U.S. state and foreign jurisdictions. It is possible that these examinations may be resolved within the next 12 months . We do not believe our gross unrecognized tax benefits will change as a result. Foreign and U.S. state jurisdictions have statutes of limitations generally ranging from three to five years. We do not provide for U.S. income taxes on the portion of undistributed earnings of foreign subsidiaries that is intended to be permanently reinvested. The cumulative amount of such undistributed earnings totaled approximately $682 million as of December 31, 2015 . These earnings could become taxable in the United States upon the sale or liquidation of these foreign subsidiaries or upon the remittance of dividends. It is not practical to calculate the residual income tax which would result if these basis differences reversed due to the complexities of the tax law and the hypothetical nature of the calculations.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The reconciliation of basic income per share to diluted income per share is shown in the following table: (millions, except per-share data) 2015 2014 2013 Income from continuing operations $ 991 $ 39 $ 48 Net income (loss) attributable to noncontrolling interest — 1 $ (1 ) Income from continuing operations attributable to USG $ 991 $ 38 $ 49 Loss from discontinued operations — (1 ) (2 ) Net income attributable to USG $ 991 $ 37 $ 47 Effect of dilutive securities - Deferred compensation program for non-employee directors (1 ) — — Income available to shareholders $ 990 $ 37 $ 47 Average common shares 145.5 141.7 108.9 Dilutive RSUs, MSUs, performance shares and stock options 1.6 2.4 2.5 Deferred shares associated with a deferred compensation program for non-employee directors 0.1 0.2 — Average diluted common shares 147.2 144.3 111.4 Basic earnings (loss) per average common share: Income from continuing operations attributable to USG $ 6.81 $ 0.27 $ 0.45 Loss from discontinued operations — (0.01 ) (0.02 ) Net income attributable to USG $ 6.81 $ 0.26 $ 0.43 Diluted earnings (loss) per average common share: Income from continuing operations attributable to USG $ 6.73 $ 0.26 $ 0.44 Loss from discontinued operations — (0.01 ) (0.02 ) Net income attributable to USG $ 6.73 $ 0.25 $ 0.42 Stock options, RSUs, MSUs, performance shares, common shares issuable upon conversion of our 10% convertible senior notes and deferred shares associated with our deferred compensation program for non-employee directors that were not included in the computation of diluted earnings (loss) per share for those periods because their inclusion was anti-dilutive were as follows: (millions, common shares) 2015 2014 2013 Stock options, RSUs, MSUs and performance shares 1.9 2.1 2.2 10% convertible senior notes due 2018 (a) — — 6.6 Deferred shares associated with a deferred compensation program for non-employee directors — — 0.2 (a) In December 2013 and April 2014, we converted $ 325 million and $75 million , respectively, of our 10% convertible senior notes due 2018 into common shares.

Stockholder Rights Plan

Stockholder Rights Plan	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Stockholder Rights Plan	Stockholder Rights Plan We have a stockholder rights plan, or the Rights Plan, established under the terms of a rights agreement dated December 21, 2006, as amended, with Computershare Trust Company N.A., as Rights Agent, or the Rights Agreement. The Rights Plan was initially intended to protect our stockholders from coercive takeover practices or takeover bids that are inconsistent with their best interests. However, in 2013 and 2015, the Board of Directors adopted amendments to the Rights Agreement, discussed below, intended to protect our substantial NOL carryforwards and related tax benefits. The Board of Directors also recommended, and on May 9, 2013 our stockholders approved, an amendment to our Restated Certificate of Incorporation, or the Protective Amendment, also intended to protect our NOL carryforwards and related tax benefits. NOL Protective Amendments to our Rights Plan On March 22, 2013, our Board of Directors approved an amendment to the Rights Agreement in an effort to protect our NOL carryforwards and related tax benefits. Our ability to use our NOLs could be substantially reduced if we experience an “ownership change,” as defined under Section 382 of the Internal Revenue Code of 1986, as amended (the "Code"), and the Rights Agreement has been designed to prevent such an “ownership change.” “Ownership changes” generally relate to the cumulative change in ownership among stockholders with an ownership interest of 5% or more (as determined under the Code’s rules) over a rolling three -year period. Our stockholders ratified, on an advisory basis, the March 22, 2013 amendment to our Rights Agreement at our 2013 annual meeting of stockholders. The Rights Agreement, as amended, provides that if any person becomes the beneficial owner of 4.9% or more of our common stock, stockholders other than the 4.9% triggering stockholder will have the right to purchase additional shares of our common stock at half the market price, thereby diluting the triggering stockholder; provided that stockholders whose beneficial ownership, as defined in Section 383 of the Code, exceeded 4.9% of our common stock outstanding on February 11, 2015 will not be deemed to have triggered the Rights Agreement, as amended, so long as they do not thereafter acquire additional common stock other than in certain specified exempt transactions. The Board of Directors approved an amendment to the Rights Agreement in February 2015 to align the definition of “Beneficial Owner” and “Beneficially Own” with Section 382 of the Code. The NOL protective provisions in the Rights Agreement adopted in 2013 were scheduled to expire on March 22, 2016 and the Rights Agreement was scheduled to expire on January 2, 2017. In connection with a required triennial review of the Rights Agreement, the Board of Directors approved, and on November 16, 2015 the Company entered into, another amendment to the Rights Agreement to extend the term of the Rights Agreement, as well as the NOL protective provisions adopted in 2013, to May 31, 2019, subject to other earlier termination events as described therein. Accordingly, the 4.9% threshold described above is now effective until the earlier of (i) May 31, 2019, (ii) the date on which our Board of Directors determines that the amendment is no longer necessary for the provision of certain tax benefits because of the repeal of Section 382 of the Code, (iii) the first day of a taxable year as to which our Board of Directors determines that no tax benefits may be carried forward, or (iv) such other date as our Board determines that the amendment is no longer necessary for the preservation of tax benefits. The rights issued pursuant to the Rights Agreement will expire on May 31, 2019. However, our Board of Directors has the power to accelerate or extend the expiration date of the rights. In addition, a board committee composed solely of independent directors reviews the Rights Agreement at least once every three years to determine whether to modify the Rights Plan in light of all relevant factors. This review was most recently conducted in November 2015. The next review is required by the end of 2018. Protective Amendment to Charter On May 9, 2013, we filed an amendment to our Restated Certificate of Incorporation, or the Protective Amendment, that restricts certain transfers of our common stock. The Protective Amendment is intended to protect the tax benefits of our NOL carryforwards. See Note 15 for a description of our NOL carryforwards. Subject to certain limited exceptions, the Protective Amendment's transfer restrictions restrict any person from transferring our common stock (or any interest in our common stock) if the transfer would result in a stockholder (or several stockholders, in the aggregate, who hold their stock as a “group” under Section 382 of the Code) owning 4.9% or more of our common stock. Any direct or indirect transfer attempted in violation of the Protective Amendment would be void as of the date of the prohibited transfer as to the purported transferee, and the purported transferee would not be recognized as the owner of the shares attempted to be owned in violation of the Protective Amendment for any purpose, including for purposes of voting and receiving dividends or other distributions in respect of that common stock, or in the case of options, receiving our common stock in respect of their exercise. The Protective Amendment is effective until the earlier of (i) May 9, 2016, (ii) the repeal of Section 382 of the Code if our Board of Directors determines that the Protective Amendment is no longer necessary for the preservation of tax benefits, (iii) the first day of a taxable year as to which our Board of Directors determines that no tax benefits may be carried forward, or (iv) such other date as determined by our Board of Directors pursuant to the Protective Amendment. On November 12, 2015, our Board of Directors also recommended that stockholders vote to extend the Protective Amendment until May 31, 2019 (subject to other earlier termination events as described in the Protective Amendment). Treatment of Berkshire Hathaway under Rights Agreement and Protective Amendment Berkshire Hathaway and certain of its affiliates may acquire beneficial ownership of up to 50% of our voting stock on a fully-diluted basis without triggering the ownership thresholds in the Protective Amendment or Rights Agreement, and may acquire beneficial ownership of more than 50% of our voting stock on a fully-diluted basis without triggering the ownership thresholds in the Protective Amendment or Rights Agreement through an offer to purchase all of our common stock that remains open for at least 60 days, in each case subject to specified exceptions.

Lease Commitments

Lease Commitments	12 Months Ended
	Dec. 31, 2015
Lease Commitments [Abstract]
Lease Commitments	Lease Commitments We lease some of our offices, buildings, machinery and equipment, and autos under noncancelable operating leases. These leases have various terms and renewal options. Lease expense amounted to $75 million in 2015 , $75 million in 2014 and $73 million in 2013 . Future minimum lease payments required under operating leases with initial or remaining noncancelable terms in excess of one year as of December 31, 2015 were as follows: (millions) 2016 2017 2018 2019 2020 After 2020 Future minimum lease payments $ 72 $ 65 $ 53 $ 40 $ 26 $ 32

Litigation

Litigation	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Litigation	Litigation WALLBOARD PRICING CLASS ACTION LAWSUITS In late 2012, USG Corporation and United States Gypsum Company were named as defendants in putative class action lawsuits alleging that since at least September 2011, U.S. wallboard manufacturers conspired to fix and raise the price of gypsum wallboard sold in the United States and to effectuate the alleged conspiracy by ending the practice of providing job quotes on wallboard. These lawsuits, brought on behalf of direct and indirect wallboard purchasers in the U.S., were consolidated for pretrial proceedings in multi-district litigation in the United States District Court for the Eastern District of Pennsylvania, under the title In re: Domestic Drywall Antitrust Litigation , MDL No. 2437. Similar lawsuits have been filed in Quebec, Ontario and British Columbia courts on behalf of purchasers of wallboard in Canada. The Canadian lawsuits also name as defendants CGC Inc., our Canadian operating subsidiary, as well as other Canadian and U.S. wallboard manufacturers. USG has denied the allegations made in these wallboard pricing lawsuits, believes these cases are without merit, and that USG’s pricing and selling policies were and are made independently and in full compliance with the law. Class action antitrust litigation in the United States, however, is expensive, protracted, and carries the risk of triple damages and joint and several liability. To avoid the expense, risk and further distraction of management, in late 2014, we agreed to a settlement of the U.S. class actions, and in the third quarter of 2014, we recorded a $48 million charge for the settlements ( $39.25 million for the direct purchaser settlement and $8.75 million for the indirect purchaser settlement). In 2015, the court entered final judgment orders approving both the direct and indirect purchaser settlements. No member of the direct purchaser class appealed from the final judgment order approving the direct purchaser settlement, and therefore, that settlement is final. One person appealed from the final judgment order approving the indirect purchaser settlement, and therefore that settlement is not yet final. We believe that the appeal is without merit and that the indirect purchaser settlement order will be affirmed on appeal, but the indirect purchaser settlement will not become final unless and until the appeal is favorably resolved. The settlement of the U.S. class action lawsuits described above does not include the Canadian lawsuits. At this stage of the Canadian lawsuits, we are not able to estimate the amount, if any, of any reasonably possible loss or range of reasonably possible losses. We believe, however, that these Canadian lawsuits will not have a material effect on our business, financial condition, operating results or cash flows. In addition to the class action lawsuits, in the first quarter of 2015, USG, United States Gypsum Company, L&W Supply Corporation, and seven other wallboard manufacturers were named as defendants in a lawsuit filed in federal court in California by twelve homebuilders asserting individual claims similar to the claims asserted in the U.S. class action lawsuits. The lawsuit has been transferred to the United States District Court for the Eastern District of Pennsylvania that is presiding over the U.S. class action lawsuits. We believe that the cost, if any, of resolving these homebuilders’ claims will not materially increase our exposure above the $48 million agreed to in the U.S. class action settlements. ENVIRONMENTAL LITIGATION We have been notified by state and federal environmental protection agencies of possible involvement as one of numerous “potentially responsible parties” in a number of Superfund sites in the United States. As a potentially responsible party, we may be responsible to pay for some part of the cleanup of hazardous waste at those sites. In most of these sites, our involvement is expected to be minimal. In addition, we are involved in environmental cleanups of other property that we own or owned. As of December 31, 2015 and December 31, 2014 , we had an accrual of $16 million for our probable and reasonably estimable liability in connection with these matters. Our accruals take into account all known or estimated undiscounted costs associated with these sites, including site investigations and feasibility costs, site cleanup and remediation, certain legal costs, and fines and penalties, if any. However, we continue to review these accruals as additional information becomes available and revise them as appropriate. Based on the information known to us, we believe these environmental matters will not have a material effect on our results of operations, financial position or cash flows. OTHER LITIGATION We are named as defendants in other claims and lawsuits arising from our operations, including claims and lawsuits arising from the operation of our vehicles, product performance or warranties, personal injury and commercial disputes. We believe that we have properly accrued for our probable liability in connection with these claims and suits, taking into account the probability of liability, whether our exposure can be reasonably estimated and, if so, our estimate of our liability or the range of our liability. We do not expect these or any other litigation matters involving USG to have a material effect on our results of operations, financial position or cash flows.

Quarterly Financial Data (unaud

Quarterly Financial Data (unaudited)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data (unaudited)	Quarterly Financial Data (unaudited) Quarter (millions, except per-share data) First Second Third Fourth 2015 Net sales $ 909 $ 970 $ 972 $ 925 Gross profit 153 183 183 172 Operating profit 76 105 102 98 Income from continuing operations (b) 24 79 76 812 Loss from discontinued operations, net of tax — — — — Net income attributable to USG (b) 24 79 76 812 Income from continuing operations per common share: Basic (a) 0.16 0.54 0.52 5.58 Diluted (a) 0.16 0.54 0.52 5.51 2014 Net sales $ 850 $ 948 $ 972 $ 954 Gross profit 143 175 176 160 Operating profit (loss) (c) 66 98 22 (24 ) Income (loss) from continuing operations (c) 45 58 (11 ) (53 ) Loss from discontinued operations, net of tax — (1 ) — — Net income (loss) attributable to USG (c) 45 57 (12 ) (53 ) Income (loss) from continuing operations per common share: Basic (a) 0.33 0.40 (0.09 ) (0.36 ) Diluted (a) 0.32 0.39 (0.09 ) (0.36 ) (a) The sum of the four quarters is not necessarily the same as the total for the year. (b) Income from continuing operations and net income attributable to USG for the fourth quarter of 2015 included a reversal of an income tax valuation allowance of $731 million . (c) Operating profit (loss), income (loss) from continuing operations, and net income (loss) attributable to USG for the third quarter of 2014 included a litigation settlement charge of $48 million and long-lived asset impairment charges of $30 million and for the fourth quarter of 2014 included a long-lived asset impairment charge of $60 million , contract termination charge and loss of receivable of $15 million , and pension settlement charges of $13 million .

Schedule II - Valuation And Qua

Schedule II - Valuation And Qualifying Accounts	12 Months Ended
	Dec. 31, 2015
Valuation and Qualifying Accounts [Abstract]
Schedule II - Valuation And Qualifying Accounts	SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS Additions (millions) Balance at beginning of period Charged to costs and expenses Charged to other accounts Deductions (a) Balance at end of period Year ended December 31, 2015: Doubtful accounts $ 20 (6 ) — (3 ) 11 Cash discounts 2 49 — (48 ) 3 Income tax valuation allowance 1,023 — — (948 ) 75 Year ended December 31, 2014: Doubtful accounts 10 9 1 — 20 Cash discounts 2 45 — (45 ) 2 Income tax valuation allowance 995 1 112 (85 ) 1,023 Year ended December 31, 2013: Doubtful accounts 14 — 1 (5 ) 10 Cash discounts 2 42 — (42 ) 2 Income tax valuation allowance 1,125 (2 ) — (128 ) 995 (a) Reflects receivables written off as related to doubtful accounts, discounts allowed as related to cash discounts and reductions in the income tax valuation allowance.

Significant Accounting Polici31

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Nature of Operations	Nature of Operations USG, through its subsidiaries, is a leading manufacturer and distributor of building materials. We produce a wide range of products for use in new residential, new nonresidential, and residential and nonresidential repair and remodel construction as well as products used in certain industrial processes. Our products also are distributed through building materials dealers, home improvement centers and other retailers, specialty wallboard distributors, and contractors.
Segments	Segments Our segments are structured around our key products and business units: Gypsum, Ceilings, Distribution and UBBP. Our Gypsum reportable segment is an aggregation of the operating segments of the gypsum businesses in the United States, Canada, Mexico, and Latin America, our mining operation in Little Narrows, Nova Scotia, Canada, and our shipping company, which we exited in 2015. Gypsum manufactures products throughout the United States, Canada, and Mexico. These products include USG Sheetrock ® brand gypsum wallboard and related products including Sheetrock ® brand joint compound, Durock ® brand cement board, Levelrock ® brand of poured gypsum flooring, Fiberock ® brand backerboard, and Securock ® brand glass mat sheathing used for building exteriors and gypsum fiber and glass mat panels used as roof cover board. Ceilings manufactures ceiling tile in the United States and ceiling grid in the United States, Canada and through February 27, 2014, the Asia-Pacific region. Distribution delivers gypsum wallboard, drywall metal, ceilings products, joint compound and other building products throughout the United States. UBBP manufactures, distributes and sells certain building products, mines raw gypsum and sells natural and synthetic gypsum throughout Asia, Australasia and the Middle East.
Consolidation and Presentation	Consolidation and Presentation Our consolidated financial statements include the accounts of USG Corporation, its majority-owned subsidiaries and through February 27, 2014, variable interest entities. Entities in which we have more than a 20% but not more than 50% ownership interest are accounted for using the equity method of accounting. All intercompany balances and transactions are eliminated in consolidation. On our consolidated statements of operations for the year ended December 31, 2013, income from equity method investments, which was previously included in "Other income, net," is reflected as "Income (loss) from equity method investments" and long-lived asset impairment charges, which was previously included in "Restructuring and long-lived asset impairment charges," are reflected as "Long-lived asset impairment charges" to conform to the current year presentation. On our consolidated statements of cash flows for the year ended December 31, 2013, income from equity method investments previously included in "Other, net" has been reclassified to "Income (loss) from equity method investments." On September 15, 2015, we entered into an agreement to sell our 50% interest in the Knauf-USG joint venture to our joint venture partner and completed the sale in December 2015. On our consolidated statements of operations for the years ended December 31, 2014 and 2013, income from this equity method investment, which was previously included in "Income from equity method investments" is reflected as "Income and gain from the sale of equity method investment to related party" to conform to the current year presentation. Presentation of this income on the consolidated statement of cash flows is within "Income from equity method investments." Our investments with Boral in the 50 / 50 joint ventures, UBBP, commenced on February 27, 2014, and as a result, our share of ten months of the results of UBBP were recorded in our accompanying consolidated statement of operations for the year ended December 31, 2014. See Note 3 for further description of our investments in UBBP.
Use of Estimates	Use of Estimates The preparation of our consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions. These estimates and assumptions affect the reported amounts of assets, liabilities, revenues and expenses. Actual results could differ from these estimates.
Revenue Recognition	Revenue Recognition We recognize revenue when substantially all the risks and rewards of ownership transfer to the customer. We record provisions for discounts to customers based on the terms of sale in the same period in which the related sales are recorded. We record estimated reductions to revenue for customer programs and incentive offerings, including promotions and other volume-based incentives, in the period in which the sale occurs.
Shipping and Handling Costs	Shipping and Handling Costs Shipping and handling costs are included in cost of products sold.
Advertising	Advertising Advertising expenses consist of media advertising and related production costs and sponsorships. We charge advertising expenses to earnings as incurred. These expenses amounted to $ 17 million , $ 23 million and $22 million for the years ended December 31, 2015 , 2014 and 2013 , respectively.
Research and Development	Research and Development We charge research and development expenditures to earnings as incurred. These expenditures amounted to $23 million , $23 million and $21 million for the years ended December 31, 2015 , 2014 and 2013 , respectively.
Litigation Costs	Litigation Costs We expense litigation costs as incurred.
Income Taxes	Income Taxes We record income tax expense (benefit) under the asset and liability method. Under this method, deferred tax assets and liabilities are recognized based on temporary differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply in the years in which the temporary differences are expected to be recovered or paid. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in earnings in the period when the change is enacted. Valuation allowances are recorded to reduce deferred tax assets when it is more likely than not that a tax benefit will not be realized.
Inventory Valuation	Inventory Valuation All of our inventories are stated at the lower of cost or market. Virtually all of our inventories are valued under the average cost method with the remainder valued under the first-in, first-out cost method. Our manufactured inventories include materials, labor and applicable factory overhead costs whereas our distribution inventories are valued at their cost. Depreciation associated with manufacturing assets is excluded from inventory cost, but is included in cost of products sold.
Earnings per Share	Earnings per Share Basic earnings per share is based on the weighted average number of common shares outstanding. Diluted earnings per share is based on the weighted average number of common shares outstanding plus the dilutive effect, if any, of market share units, or MSUs, restricted stock units, or RSUs, and performance shares, and the potential exercise of outstanding stock options. Prior to the conversion of our 10% convertible senior notes, the dilutive effect of the potential conversion of the 10% convertible senior notes was included for the appropriate time periods when these instruments were outstanding.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents include highly liquid investments, primarily money market funds, with maturities of three months or less at the time of purchase.
Marketable Securities	Marketable Securities Marketable securities are classified as available-for-sale securities and reported at fair value, with unrealized gains and losses excluded from earnings and reported in accumulated other comprehensive income (loss), or AOCI. If it is deemed that marketable securities have unrealized losses that are other than temporary, these losses will be recorded in earnings immediately. Situations in which losses may be considered other than temporary include when we have decided to sell a security or when it is more likely than not that we will be required to sell the security before we recover its amortized cost basis. Cost basis for securities sold are determined on a first-in-first-out basis.
Receivables	Receivables We include trade receivables in receivables on our consolidated balance sheets. Receivables are recorded at net realizable value, which includes allowances for cash discounts and doubtful accounts. We review the collectability of receivables on an ongoing basis. We reserve for receivables determined to be uncollectible. This determination is based on the delinquency of the account, the financial condition of the customer and our collection experience. We include short-term financing receivables in receivables and long-term financing and loan receivables in other assets on our consolidated balance sheets. Financing and loan receivables are recorded at net realizable value which includes an allowance for credit losses. We review the collectability of financing and loan receivables on an ongoing basis. We reserve for financing and loan receivables determined to be uncollectible. This determination is based on the delinquency of the account and the financial condition of the other party. As of December 31, 2015 , the allowance for credit losses was immaterial.
Investments in Unconsolidated Joint Ventures	Investments in Unconsolidated Joint Ventures The equity method of accounting is used for investments in joint ventures that we do not consolidate, but over which we have the ability to exercise significant influence. Profits resulting from sales with equity method investees are eliminated until realized by the investee. Losses in the value of an investment in an unconsolidated joint venture that are other than temporary, are recognized when the current fair value of the investment is less than its carrying value.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment is recorded at cost. We record depreciation of property, plant and equipment on a straight-line basis over the expected useful lives of the assets. We have determined estimated useful lives to be 50 years for buildings and improvements, a range of 10 to 25 years for machinery and equipment, and a range of 5 to 7 years for computer software and systems development costs. Leasehold improvements are capitalized and amortized over the shorter of the remaining lease term or remaining economic useful life. We compute depletion on a basis calculated to spread the cost of gypsum and other applicable resources over the estimated quantities of material recoverable. We capitalize interest during the active construction period of major capital projects. Capitalized interest is added to the cost of the underlying assets and is depreciated over the useful lives of those assets. We recorded $3 million of capitalized interest in each of the three years ended December 31, 2015 . Facility start-up costs that cannot be capitalized are expensed as incurred and recorded in cost of products sold. Property, plant and equipment is reviewed for impairment when indicators of a potential impairment are present by comparing the carrying values of the assets with their estimated future undiscounted cash flows. If we determine an impairment exists, the asset is written down to estimated fair value.
Intangible Assets	Intangible Assets We perform impairment tests for intangible assets with indefinite useful lives as of October 31 of each year, or more frequently if events occur or circumstances change that would more likely than not reduce the fair value of an intangible asset below its carrying value. The impairment test for assets with indefinite lives consists of a comparison of the fair value of the asset with its carrying amount. If the carrying amount of an intangible asset exceeds its fair value, an impairment loss is recognized in an amount equal to that excess. Intangible assets determined to have indefinite useful lives, primarily comprised of trade names, are not amortized. An income approach is used for valuing trade names. Assumptions used in the income approach include projected revenues and assumed royalty, long-term growth and discount rates. We perform impairment tests on definite lived intangible assets, such as customer relationships, upon identification of events or circumstances that may indicate the carrying amount of the assets might be unrecoverable by comparing their undiscounted cash flows with their carrying value. If we determine impairment exists, the assets are written down to estimated fair value. As of December 31, 2015 , we had no intangible assets in other current assets on the consolidated balance sheet classified as assets held for sale. As of December 31, 2014 , we had $5 million of intangible assets classified as assets held for sale.
Share-Based Compensation	Share-Based Compensation We award share-based compensation to employees in the form of stock options, restricted stock units, market share units, and performance shares and to non-employee directors in the form of shares of our common stock. All grants under share-based payment programs are accounted for at fair value at the date of grant. We recognize expense on all share-based awards to employees expected to vest over the service period, which is the shorter of the period until the employees’ retirement eligibility dates or the service period of the award.
Derivative Instruments	Derivative Instruments We use derivative instruments to manage selected commodity price and foreign currency exposures. We do not use derivative instruments for speculative trading purposes, and we typically do not hedge beyond three years . All derivative instruments are recorded on the balance sheet at fair value. For derivatives designated as fair value hedges, the changes in the fair values of both the derivative instrument and the hedged item are recognized in earnings in the current period. For derivatives designated as cash flow hedges, the effective portion of changes in the fair value of the derivative is recorded to AOCI, and is reclassified to earnings when the underlying forecasted transaction affects earnings. The ineffective portion of changes in the fair value of the derivative is reported in cost of products sold in the current period. We periodically reassess the probability of the underlying forecasted transaction occurring. For derivatives designated as net investment hedges, we record changes in fair value to AOCI. For derivatives not designated as hedging instruments, all changes in fair value are recorded to earnings in the current period. Currently, we are using swaps to hedge a significant portion of our anticipated purchases of natural gas to be used in our manufacturing operations. Generally, we hedge the cost of a majority of our anticipated purchases of natural gas over the next 12 months . However, we review our positions regularly and make adjustments as market conditions warrant. The majority of contracts currently in place are designated as cash flow hedges and the remainder are not designated as hedging instruments. We have operations outside of the United States and use forward contracts from time-to-time to hedge the risk of changes in cash flows resulting from selected forecasted intercompany and third-party sales or purchases, as well as intercompany loans, denominated in non-U.S. currencies, or to hedge the risk of selected changes in our net investment in foreign subsidiaries. These contracts are designated as either cash flow or net investment hedges or are not designated as hedging instruments.
Foreign Currency Translation	Foreign Currency Translation We translate foreign-currency-denominated assets and liabilities into U.S. Dollars at the exchange rates existing as of the respective balance sheet dates. We translate income and expense items at the average exchange rates during the respective periods. We record translation adjustments resulting from fluctuations in exchange rates to AOCI on our consolidated balance sheets and our share of the translation adjustments recorded by our equity method investments to AOCI. We record transaction gains and losses to earnings. The total transaction loss was $7 million in 2015 , $6 million in 2014 and $4 million in 2013 .
Fair Value Measurements	Fair Value Measurements Certain assets and liabilities are required to be recorded at fair value. The estimated fair values of those assets and liabilities have been determined using market information and valuation methodologies. Changes in assumptions or estimation methods could affect the fair value estimates. However, we do not believe any such changes would have a material impact on our financial condition, results of operations or cash flows. There are three levels of inputs that may be used to measure fair value: • Level 1 – Quoted prices for identical assets and liabilities in active markets; • Level 2 – Quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; and model-derived valuations in which all significant inputs and significant value drivers are observable in active markets; and • Level 3 – Valuations derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable. Certain assets and liabilities are measured at fair value on a nonrecurring basis rather than on an ongoing basis, but are subject to fair value adjustments in certain circumstances, such as when there is evidence of impairment or when a new liability is being established that requires fair value measurement.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In January 2016, the Financial Accounting Standards Board, or FASB, issued Accounting Standard Update, or ASU, 2016-01 “Recognition and Measurement of Financial Assets and Financial Liabilities,” which requires that most equity instruments be measured at fair value, with subsequent changes in fair value recognized in net income. The pronouncement also impacts the financial liabilities under the fair value option and the presentation and disclosure requirements for financial instruments. The ASU does not apply to equity method investments or investments in consolidated subsidiaries. The new standard will be effective for us for the year ended December 31, 2018, with early adoption permitted and amendments to be applied as a cumulative-effect adjustment to the balance sheet in the year of adoption. We are currently in the process of assessing the impact of the ASU on our consolidated financial statements and disclosures. In November 2015, the FASB issued ASU 2015-17, "Balance Sheet Classification of Deferred Taxes", which requires entities to present all deferred tax assets and liabilities as noncurrent. We early adopted the standard as of December 31, 2015 and have reclassified our current deferred tax assets and liabilities to long-term. For the year ended December 31, 2014, our consolidated balance sheet has been retrospectively adjusted to conform with the new presentation, which resulted in a reclassification of $1 million from current assets to long-term assets and $44 million from current assets to long-term liabilities. In July 2015, the FASB issued ASU 2015-11, "Simplifying the Measurement of Inventory", which changes the measurement principle for inventory from the lower of cost or market to the lower of cost or net realizable value for entities that measure inventory using the first-in, first-out (FIFO) or average cost method. The ASU defines net realizable value as estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The standard will be effective for us in the first quarter of 2017, with early adoption permitted. We do not expect the adoption of ASU 2015-11 will have a significant impact to our consolidated financial statements or disclosures. In May 2015, the FASB issued ASU 2015-07, "Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent)," which updates the disclosure requirements for investments that are measured at net asset value using the practical expedient. These investments are to be removed from the fair value hierarchy and shown as a reconciling item. The standard will be effective for us in the first quarter of 2016. The adoption will not have a significant impact to our disclosures. In April 2015, the FASB issued ASU 2015-03, "Simplifying the Presentation of Debt Issuance Costs", which requires costs related to a recognized debt liability to be presented on the consolidated balance sheet as a direct deduction from the debt liability rather than as an asset. In August 2015, the FASB issued ASU 2015-15, "Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements", which clarifies that the SEC staff would not object to an entity deferring and presenting debt issuance costs as an asset, regardless of whether there are any outstanding borrowings on the line-of-credit. We adopted these standards as of December 31, 2015 and have reclassified our deferred debt issuance costs associated with our debt other than our line-of-credit from other assets to debt. For the year ended December 31, 2014, our consolidated balance sheet has been adjusted to conform with the new presentation, which resulted in a reclassification of $14 million from other assets to debt. In August 2014, the FASB issued ASU 2014-15, "Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern," which requires, in connection with preparing financial statements for each annual and interim reporting period, management to evaluate whether there are conditions or events that raise substantial doubts about the entity's ability to continue as a going concern within one year after the date that the financial statements are issued and provide related disclosures. The standard will be effective for us in the first quarter of 2016. We do not expect that the adoption of ASU 2014-15 will have a significant impact to our disclosures. In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers,” which supersedes the revenue recognition requirements in “Revenue Recognition (Topic 605),” and requires entities to recognize revenue in a way that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled to in exchange for those goods or services. There are two transition methods available under the new standard, either cumulative effect or retrospective. The standard will be effective for us in the first quarter of 2018. We will adopt the new standard using the modified retrospective approach, which requires the standard be applied only to the most current period presented, with the cumulative effect of initially applying the standard recognized at the date of initial application. We are evaluating the effect of adopting this standard, but we do not expect that the adoption of ASU 2014-09 will have a significant impact to our consolidated financial statements or disclosures.

Equity Method Investments (Tabl

Equity Method Investments (Tables)	12 Months Ended
	Dec. 31, 2015
Equity Method Investments and Joint Ventures [Abstract]
Schedule of equity method investments	Equity method investments were as follows: December 31, 2015 December 31, 2014 (millions) Carrying Value Ownership Percentage Carrying Value Ownership Percentage USG Boral Building Products $ 675 50% $ 689 50% Other equity method investments (a) 7 33% - 50% $ 46 33% - 50% Total equity method investments $ 682 $ 735 (a) As of December 31, 2014, our investment in the Knauf-USG joint venture was $38 million .
Schedule of translation gains or losses recorded in other comprehensive income	Translation gains or losses recorded in other comprehensive income were as follows: (millions) 2015 2014 2013 Translation loss $ (23 ) $ (34 ) $ —
Statement of Operations from equity method investments	Statement of Operations For the year ended December 31, (millions) 2015 2014 (a) 2013 USG Boral Building Products: Net sales $ 1,003 $ 927 N/A Gross profit 278 251 N/A Operating profit 124 95 N/A Net income from continuing operations 101 72 N/A Net income 101 72 N/A Net income attributable to USG Boral Building Products 96 67 N/A USG share of income from USG Boral Building Products 48 33 N/A Other equity method investments (b) : USG share of income from other investments accounted for using the equity method 2 2 1 Total income from equity method investments 50 35 1 (a) Operating results are presented for UBBP for the ten months months ended December 31, 2014 . (b) Amounts represent our share of income or loss from all equity method investments, other than UBBP. For the twelve months ended December 31, 2014, the amount reflected includes two months of our share of income from equity method investments from the joint ventures which we owned prior to being contributed to UBBP on February 27, 2014.
Balance Sheet from equity method investments	Balance Sheet (millions) December 31, 2015 December 31, 2014 USG Boral Building Products: Current assets $ 368 $ 446 Non-current assets 935 989 Current liabilities (c) 197 245 Long-term debt (d) 40 46 Other non-current liabilities 17 21 Shareholders' equity (e) 1,049 1,123 (c) Includes the current portion of long-term debt of $16 million and $35 million as of December 31, 2015 and 2014 , respectively. (d) Includes term loans and credit facilities for the joint ventures in Oman which were contributed to UBBP in February 2014. The loans and credit facilities are guaranteed by us and the Zawawi Group in Oman. (e) Shareholders' equity includes $60 million and $70 million related to non-controlling interests as of December 31, 2015 and 2014 , respectively.

Marketable Securities (Tables)

Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Schedule of investments in marketable securities	Our investments in marketable securities as of December 31, 2015 and 2014 consisted of the following: 2015 2014 (millions) Amortized Cost Fair Value Amortized Cost Fair Value Corporate debt securities $ 134 $ 134 $ 93 $ 93 U.S. government and agency debt securities 57 57 22 22 Asset-backed debt securities 21 21 17 17 Certificates of deposit 15 15 18 18 Municipal debt securities 3 3 4 4 Total marketable securities $ 230 $ 230 $ 154 $ 154
Schedule of contractual maturities of marketable securities	Contractual maturities of marketable securities as of December 31, 2015 were as follows: (millions) Amortized Cost Fair Value Due in 1 year or less $ 194 $ 194 Due in 1-5 years 36 36 Total marketable securities $ 230 $ 230

Intangible Assets (Tables)

Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of intangible assets with definite lives	Intangible assets with definite lives are amortized. These assets are summarized as follows: As of December 31, 2015 As of December 31, 2014 (millions) Gross Carrying Amount Accumulated Amortization Net Gross Carrying Amount Accumulated Amortization Net Intangible Assets with Definite Lives: Customer relationships $ 70 $ (61 ) $ 9 $ 70 $ (54 ) $ 16 Other 9 (8 ) 1 9 (7 ) 2 Total $ 79 $ (69 ) $ 10 $ 79 $ (61 ) $ 18
Schedule of estimated annual amortization expense	Estimated annual amortization expense is as follows: (millions) 2016 2017 2018 and thereafter Estimated annual amortization expense $ 7 $ 2 $ 1
Schedule of intangible assets with indefinite lives	Intangible assets with indefinite lives are not amortized. The gross carry amounts of these assets as of December 31 are as follows: (millions) 2015 2014 Intangible Assets with Indefinite Lives: Trade names $ 22 $ 22 Other 8 8 Total $ 30 $ 30

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Schedule of total debt	Total debt as of December 31 consisted of the following: (millions) 2015 2014 5.5% senior notes due 2025 $ 350 $ — 5.875% senior notes due 2021 350 350 6.3% senior notes due 2016 500 500 7.75% senior notes due 2018 500 500 7.875% senior notes due 2020 (net of discount: 2015 - $1; 2014 - $1) 249 249 8.375% senior notes due 2018 — 350 Ship mortgage facility (includes current portion of long-term debt: 2015 - $0; 2014 - $4) — 21 Industrial revenue bonds (due 2028 through 2034) 239 239 Total $ 2,188 $ 2,209 Less unamortized debt issuance costs (a) $ 13 $ 14 Total $ 2,175 $ 2,195 (a) Reflects the change in presentation of unamortized debt issuance costs from other assets to a reduction in debt. See Note 2 . The indentures governing the notes contain events of default, covenants and restrictions that are customary for similar transactions, including a limitation on our ability and the ability of certain of our subsidiaries to create or incur secured indebtedness. Interest rate (a) 6.30% 7.75% 5.500% 7.875% 5.875% Principal net of discount (in millions) (b) $500 $500 $350 $249 $350 Maturity November 15, 2016 January 15, 2018 March 1, 2025 March 30, 2020 November 1, 2021 Call date Any time (c) Any time (c) March 1, 2020 (d) March 30, 2016 (d) November 1, 2016 (d) Mandatory redemption at 101% plus accrued and unpaid interest in the event of a change in control and a related downgrade below investment grade by both Moody’s Investors Service and Standard & Poor’s Financial Services LLC at 101% plus accrued and unpaid interest in the event of a change in control (a) The 7.75% senior notes currently have an effective interest rate of 9.75% . The rate is subject to an adjustment of up to 2% if the debt rating is downgraded or subsequently upgraded by Moody's Investors Service and Standard & Poor's Financial Services LLC. (b) Principal amounts do not include unamortized debt issuance costs that have been reclassified from other assets to a reduction in debt. See Note 2 . (c) Callable at any time at a price equal to the greater of (1) 100% of the principal and (2) the sum of the present value of the remaining scheduled payments of principal and interest discounted to the redemption date on a semi-annual basis at the applicable U.S. Treasury rate plus a spread (as outlined in the respective indentures), plus any accrued and unpaid interest on the principal amount being called. (d) Callable at any time prior to the call date at a price equal to 100% of the principal plus a premium (as outlined in the respective indentures), plus any accrued and unpaid interest on the principal amount being called. Callable after the call date at stated redemption prices (as outlined in the respective indentures), plus any accrued and unpaid interest on the principal amount being called.
Schedule of amounts of total debt outstanding maturing in each of next five years and beyond	As of December 31, 2015 , the amounts of total debt outstanding maturing in each of the next five years and beyond were as follows: (millions) 2016 2017 2018 2019 2020 After 2020 Debt maturities (principal amounts) $ 500 $ — $ 500 $ — $ 250 $ 939

Derivative Instruments (Tables)

Derivative Instruments (Tables)	12 Months Ended
	Dec. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of pretax effects of derivative instruments	The following are the pretax effects of derivative instruments on the consolidated statements of operations and the consolidated statements of comprehensive income (loss) for the years ended December 31, 2015 , 2014 and 2013 : Amount of Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on Derivatives (Effective Portion) Location of Gain or (Loss) Reclassified from AOCI into Income (Effective Portion) Amount of Gain or (Loss) Reclassified from AOCI into Income (Effective Portion) (millions) 2015 2014 2013 2015 2014 2013 Derivatives in Cash Flow Hedging Relationships Commodity contracts $ (14 ) $ (19 ) $ 1 Cost of products sold $ (15 ) $ 2 $ (2 ) Foreign exchange contracts 12 4 3 Cost of products sold 7 2 3 Foreign exchange contracts 1 — — Income and gain from the sale of equity method investment to related party 1 — — Total $ (1 ) $ (15 ) $ 4 $ (7 ) $ 4 $ 1 Location of Gain or (Loss) Recognized in Income on Derivatives Amount of Gain or (Loss) Recognized in Income on Derivatives (millions) 2015 2014 2013 Derivatives Not Designated as Hedging Instruments Commodity contracts Cost of products sold $ (3 ) $ (4 ) $ 2 Foreign exchange contracts Other (income) expense, net 2 — — Total $ (1 ) $ (4 ) $ 2
Schedule of fair values of derivative instruments	The following are the fair values of derivative instruments on the consolidated balance sheets as of December 31, 2015 and 2014 : Balance Sheet Location Fair Value Balance Sheet Location Fair Value (millions) 12/31/15 12/31/14 12/31/15 12/31/14 Derivatives in Cash Flow Hedging Relationships Commodity contracts Other current assets $ 1 $ 1 Accrued expenses $ 15 $ 14 Commodity contracts Other assets — — Other liabilities 5 7 Foreign exchange contracts Other current assets 8 3 Accrued expenses — — Total derivatives in hedging relationships $ 9 $ 4 $ 20 $ 21 Balance Sheet Location Fair Value Balance Sheet Location Fair Value (millions) 12/31/15 12/31/14 12/31/15 12/31/14 Derivatives Not Designated as Hedging Instruments Commodity contracts Other current assets $ — $ — Accrued expenses $ 2 $ 4 Commodity contracts Other assets — — Other liabilities — 1 Total derivatives not designated as hedging instruments $ — $ — $ 2 $ 5 Total derivatives Total assets $ 9 $ 4 Total liabilities $ 22 $ 26

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Schedule of assets and liabilities measured at fair value on a recurring basis	Our assets and liabilities measured at fair value on a recurring basis were as follows: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total (millions) 12/31/15 12/31/14 12/31/15 12/31/14 12/31/15 12/31/14 12/31/15 12/31/14 Cash equivalents $ 223 $ 93 $ 25 $ 32 $ — $ — $ 248 $ 125 Equity mutual funds 4 4 — — — — 4 4 Marketable securities: Corporate debt securities — — 134 93 — — 134 93 U.S. government and agency debt securities — — 57 22 — — 57 22 Asset-backed debt securities — — 21 17 — — 21 17 Certificates of deposit — — 15 18 — — 15 18 Municipal debt securities — — 3 4 — — 3 4 Derivative assets — — 9 4 — — 9 4 Derivative liabilities — — (22 ) (26 ) — — (22 ) (26 )

Employee Retirement Plans (Tabl

Employee Retirement Plans (Tables)	12 Months Ended
	Dec. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Summary of components of net pension and postretirement benefits costs	The components of net pension and postretirement benefit costs are summarized in the following table: (millions) 2015 2014 2013 Pension Benefits: Service cost of benefits earned $ 49 $ 37 $ 38 Interest cost on projected benefit obligation 66 65 63 Expected return on plan assets (83 ) (79 ) (76 ) Settlement (a) 1 13 16 Net amortization 39 24 43 Net pension cost $ 72 $ 60 $ 84 Postretirement Benefits: Service cost of benefits earned $ 2 $ 3 $ 3 Interest cost on projected benefit obligation 6 7 7 Net amortization (31 ) (35 ) (34 ) Net postretirement benefit $ (23 ) $ (25 ) $ (24 ) (a) In 2014, the settlement charge related to the elimination of the benefit obligation of the UK pension plan due to the purchase of annuities. In 2013, the settlement charge primarily related to lump sum payments made to certain terminated vested participants in our U.S. Plan.
Schedule of accumulated benefit obligation for the defined benefit pension plans	As of December 31, (millions) 2015 2014 Selected information for pension plans with accumulated benefit obligations in excess of plan assets: Accumulated benefit obligation $ (1,182 ) $ (1,230 ) Fair value of plan assets 1,097 1,113 Selected information for pension plans with benefit obligations in excess of plan assets: Benefit obligation $ (1,365 ) $ (1,686 ) Fair value of plan assets 1,099 1,340
Summary of projected benefit obligations, plan assets and funded status	The following table summarizes projected benefit obligations, plan assets and funded status as of December 31: Pension Postretirement (millions) 2015 2014 2015 2014 Change in Benefit Obligation: Benefit obligation as of January 1 $ 1,686 $ 1,376 $ 167 $ 166 Service cost 49 37 2 3 Interest cost 66 65 6 7 Curtailment/settlements (4 ) (24 ) — — Participant contributions 11 10 3 8 Benefits paid (86 ) (81 ) (11 ) (20 ) Plan amendment — — — 4 Actuarial (gain) loss (119 ) 327 (14 ) 4 Foreign currency translation (39 ) (24 ) (9 ) (5 ) Benefit obligation as of December 31 $ 1,564 $ 1,686 $ 144 $ 167 Change in Plan Assets: Fair value as of January 1 $ 1,340 $ 1,262 $ — $ — Actual return on plan assets 17 132 — — Employer contributions 61 64 8 12 Participant contributions 11 10 3 8 Benefits paid (86 ) (81 ) (11 ) (20 ) Curtailment/settlements (4 ) (24 ) — — Foreign currency translation (38 ) (23 ) — — Fair value as of December 31 $ 1,301 $ 1,340 $ — $ — Funded status $ (263 ) $ (346 ) $ (144 ) $ (167 ) Components on the Consolidated Balance Sheets: Noncurrent assets $ 3 $ — $ — $ — Current liabilities (9 ) (9 ) (9 ) (13 ) Noncurrent liabilities (257 ) (337 ) (135 ) (154 ) Net liability as of December 31 $ (263 ) $ (346 ) $ (144 ) $ (167 ) Pretax Components in AOCI: Net actuarial loss $ 387 $ 490 $ 7 $ 24 Prior service credit (1 ) (1 ) (108 ) (140 ) Total as of December 31 $ 386 $ 489 $ (101 ) $ (116 )
Schedule of assumptions used in the accounting for the plans	The following tables reflect the assumptions used in the accounting for our plans: Pension Postretirement 2015 2014 2015 2014 Weighted average assumptions used to determine benefit obligations as of December 31: Discount rate 4.43 % 4.10 % 4.24 % 3.70 % Compensation increase rate 3.55 % 3.60 % N/A N/A Weighted average assumptions used to determine net cost for years ended December 31: Discount rate 4.10 % 4.90 % 3.70 % 4.60 % Expected return on plan assets 6.70 % 7.00 % N/A N/A Compensation increase rate 3.50 % 3.50 % N/A N/A
Schedule of effect of one percentage point change in the assumed health care cost trend rates	A one percentage point change in the assumed health care cost trend rates would have the following effects on our U.S. and Canadian plans: (millions) One-Percentage- Point Increase One-Percentage- Point Decrease Effect on total service and interest cost $ 1 $ — Effect on postretirement benefit obligation 10 (8 )
Schedule of aggregate target asset allocation on a weighted average basis for all the plans and the acceptable ranges around the targets	The following table shows the aggregate target asset allocation on a weighted average basis for all the plans and the acceptable ranges around the targets as of December 31, 2015 . Investment Policy Target Range Asset Categories: Asset Category Description Equity Institutional commingled/pooled equity funds, equity mutual funds and direct holdings of the common stock of U.S. and non-U.S. companies; equity funds and direct holdings are invested in companies with a range of market capitalizations 40 % 36% - 42% Fixed income U.S. Treasury securities, non-U.S. government debt securities such as Canadian federal bonds, corporate bonds of companies from diversified industries and mortgage-backed securities 49 % 46% - 52% Limited partnerships Investments in funds that follow any of several different strategies, including investing in distressed debt, energy development, infrastructure, and hedge funds. These investments use strategies with returns normally expected to have a reduced correlation to the return of equities as compared to other asset classes and often provide a current income component that is a meaningful portion of the investment’s total return. 5 % 2% -8% Other real assets Primarily investments in large core, private real estate funds that directly own a diverse portfolio of properties located in the United States. It also includes an allocation to funds investing in equities of real estate and infrastructure companies 6 % 3% - 9% Cash equivalents and short-term investments Primarily held in short-term investment funds or registered money market funds with daily liquidity — % 0% - 5% Total 100 %
Schedule of fair values by hierarchy of inputs	The fair values by hierarchy of inputs as of December 31 were as follows: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total (millions) 2015 2014 2015 2014 2015 2014 2015 2014 Asset Categories: Equity: (a) Common and preferred stock $ 55 $ 74 $ — $ — $ — $ — $ 55 $ 74 Commingled/pooled/mutual funds 54 53 448 470 — — 502 523 Total equity 109 127 448 470 — — 557 597 Fixed income: U.S. government and agency debt securities — — 177 195 — — 177 195 Non-U.S. government and agency debt securities — — 32 30 — — 32 30 Investment-grade debt securities — — 199 184 — — 199 184 High-yield debt securities — — 36 39 — — 36 39 Commingled/pooled funds — — 129 114 — — 129 114 Other — — 3 8 1 1 4 9 Total fixed income — — 576 570 1 1 577 571 Limited partnerships — — — — 106 103 106 103 Other real estate assets — — 15 20 37 35 52 55 Cash equivalents and short-term investments — — 10 17 — — 10 17 Total $ 109 $ 127 $ 1,049 $ 1,077 $ 144 $ 139 $ 1,302 $ 1,343 Cash on hand — — Receivables 9 1 Accounts payable (10 ) (4 ) Total $ 1,301 $ 1,340 (a) Certain investments in commingled/pooled equity funds have been classified as Level 2 in 2015 and 2014 because observable quoted prices for these institutional funds are not available.
Reconciliation of the change in the fair value measurement of the defined benefit plans’ consolidated assets	A reconciliation of the change in the fair value measurement of the defined benefit plans’ consolidated assets using significant unobservable inputs (Level 3) between January 1, 2014 and December 31, 2015 is as follows: (millions) Fixed Income Other Real Estate Assets Limited Partnerships Total Balance as of January 1, 2014 $ 1 $ 35 $ 39 $ 75 Realized gains — 1 — 1 Unrealized gains (losses) — 1 (2 ) (1 ) Purchases, sales and settlements: Purchases — — 67 67 Sales — (2 ) (1 ) (3 ) Settlements — — — — Net transfers into (out of) Level 3 — — — — Balance as of December 31, 2014 $ 1 $ 35 $ 103 $ 139 Realized losses — (1 ) — (1 ) Unrealized gains — 5 1 6 Purchases, sales and settlements: Purchases — — 2 2 Sales — (2 ) — (2 ) Settlements — — — — Net transfers into (out of) Level 3 — — — — Balance as of December 31, 2015 $ 1 $ 37 $ 106 $ 144
Schedule of expected benefit payments	Total benefit payments we expect to make to participants, which include payments funded from USG’s assets as well as payments from our pension plans' assets, are as follows (in millions): Years ended December 31 Pension Benefits Postretirement Benefits 2016 $ 105 $ 9 2017 84 9 2018 94 10 2019 95 10 2020 128 8 2021 - 2025 585 43

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of stock options outstanding and stock option activity	A summary of stock options outstanding as of December 31, 2015 and of stock option activity during 2015 is presented below: Number of Options (000) Weighted Average Exercise Price Weighted Average Remaining Contractual Term (years) Aggregate Intrinsic Value (millions) Outstanding at January 1, 2015 3,982 $ 26.77 4.17 $ 31 Exercised (410 ) 14.61 Canceled (67 ) 41.50 Forfeited (9 ) 14.76 Outstanding at December 31, 2015 3,496 $ 28.00 3.06 $ 19 Exercisable at December 31, 2015 3,363 $ 28.51 2.93 $ 18 Vested or expected to vest at December 31, 2015 3,496 $ 28.00 2.99 $ 19
Schedule of MSUs valuation assumptions	We estimated the fair value of each MSU granted on the date of grant using a Monte Carlo simulation that used the assumptions noted in the following table. Volatility was based on stock price history immediately prior to grant for a period commensurate with the expected term. The risk-free rate was based on zero-coupon U.S. government issues at the time of grant. The expected term represents the period from the valuation date to the end of the performance period. Assumptions: 2015 2014 2013 Expected volatility 42.70 % 54.93 % 60.97 % Risk-free rate 1.09 % 0.63 % 0.35 % Expected term (in years) 2.95 2.94 2.38 Expected dividends — — —
Schedule of nonvested MSUs outstanding and activity	Nonvested MSUs outstanding as of December 31, 2015 and MSU activity during 2015 were as follows: Weighted Number of Shares (000) Weighted Average Grant Date Fair Value Nonvested at January 1, 2015 511 $ 38.43 Granted 474 30.06 Vested (156 ) 34.80 Forfeited (86 ) 34.34 Nonvested at December 31, 2015 743 34.33
Summary of nonvested RSUs outstanding and activity	RSUs outstanding as of December 31, 2015 and RSU activity during 2015 were as follows: Number of Shares (000) Weighted Average Grant Date Fair Value Nonvested at January 1, 2015 423 $ 20.12 Granted 94 28.56 Vested (220 ) 17.84 Forfeited (27 ) 24.36 Nonvested at December 31, 2015 270 24.49
Schedule of performance based units valuation assumptions	We estimated the fair value of each performance share granted on the date of grant using a Monte Carlo simulation that uses the assumptions noted in the following table. Volatility was based on stock price history immediately prior to grant for a period commensurate with the expected term. The risk-free rate was based on zero coupon U.S. government issues at the time of grant. The expected term represents the period from the grant date to the end of the three -year performance period. Assumptions: 2015 2014 2013 Expected volatility 42.70 % 54.93 % 59.98 % Risk-free rate 1.09 % 0.63 % 0.43 % Expected term (in years) 2.95 2.94 2.88 Expected dividends — — —
Summary of nonvested performance share outstanding and performance share activity	Nonvested performance shares outstanding as of December 31, 2015 and performance share activity during 2015 were as follows: Weighted Number of Shares (000) Weighted Average Grant Date Fair Value Nonvested at January 1, 2015 203 $ 42.82 Granted 147 30.63 Vested (89 ) 38.89 Forfeited (39 ) 24.12 Nonvested at December 31, 2015 222 37.20

Supplemental Balance Sheet In40

Supplemental Balance Sheet Information (Tables)	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of inventories	Inventories as of December 31 consisted of the following: (millions) 2015 2014 Finished goods $ 210 $ 232 Work in progress 36 35 Raw materials 68 62 Total $ 314 $ 329
Schedule of property, plant and equipment	Property, plant and equipment as of December 31 consisted of the following: (millions) 2015 2014 Land and mineral deposits $ 131 $ 135 Buildings and improvements 1,088 1,095 Machinery and equipment 2,505 2,563 3,724 3,793 Reserves for depreciation and depletion (1,936 ) (1,885 ) Total $ 1,788 $ 1,908 Annual depreciation and depletion expense $ 130 $ 134
Schedule of accrued expenses	Accrued expenses as of December 31 consisted of the following: (millions) 2015 2014 Self-insurance reserves $ 20 $ 21 Employee compensation 40 42 Interest 45 45 Restructuring — 1 Derivatives 17 18 Pension and other postretirement benefits 18 22 Environmental 16 16 Other 58 55 Total $ 214 $ 220
Schedule of changes in balances of each component of accumulated other comprehensive income (loss)	Changes in the balances of each component of accumulated other comprehensive income (loss), or AOCI, are summarized in the following table: (millions) Derivatives Pension and Other Postretirement Benefit Plans Foreign Total AOCI Balance as of January 1, 2013 $ 32 $ (303 ) $ 38 $ (233 ) Other comprehensive income (loss) before reclassifications 4 247 (17 ) 234 Less: Amounts reclassified from AOCI, net of tax 1 (24 ) — (23 ) Other comprehensive income (loss), net of tax 3 271 (17 ) 257 Balance as of December 31, 2013 $ 35 $ (32 ) $ 21 $ 24 Other comprehensive loss before reclassifications (15 ) (272 ) (68 ) (355 ) Less: Amounts reclassified from AOCI, net of tax 4 (2 ) 5 7 Other comprehensive loss, net of tax (19 ) (270 ) (73 ) (362 ) Balance as of December 31, 2014 $ 16 $ (302 ) $ (52 ) $ (338 ) Other comprehensive (loss) income before reclassifications (5 ) 74 (67 ) 2 Less: Amounts reclassified from AOCI, net of tax (9 ) (7 ) (6 ) (22 ) Other comprehensive income (loss), net of tax 4 81 (61 ) 24 Balance as of December 31, 2015 $ 20 $ (221 ) $ (113 ) $ (314 )
Schedule of amounts reclassified from accumulated other comprehensive income, net of tax	Amounts reclassified from AOCI, net of tax, for the years ended December 31, 2015 and 2014 , were as follows: (millions) 2015 2014 Derivatives Net reclassification from AOCI for cash flow hedges included in cost of products sold $ (8 ) $ 4 Net reclassification from ACOI for cash flow hedges included in income and gain from the sale of equity method investment to related party 1 — Less: Income tax expense on reclassification from AOCI included in income tax expense 2 — Net amount reclassified from AOCI $ (9 ) $ 4 Pension and postretirement benefits Net reclassification from AOCI for amortization of prior service (benefit) cost included in cost of products sold $ (5 ) $ 7 Net reclassification from AOCI for amortization of prior service (benefit) cost included in selling and administrative expenses (3 ) (10 ) Less: Income tax expense on reclassification from AOCI included in income tax expense (benefit) (1 ) (1 ) Net amount reclassified from AOCI $ (7 ) $ (2 ) Foreign Currency Translation Net reclassification from AOCI for translation (loss) gain realized upon the sale of foreign entities $ (6 ) $ 5 Less: Income tax expense on reclassification from AOCI included in income tax expense (benefit) — — Net amount reclassified from AOCI $ (6 ) $ 5
Schedule of changes in liability for asset retirement obligations	Changes in our liability for asset retirement obligations during 2015 and 2014 consisted of the following: (millions) 2015 2014 Balance as of January 1 $ 123 $ 132 Accretion expense 7 7 Liabilities incurred 1 2 Changes in estimated cash flows (a) (5 ) (13 ) Liabilities settled (2 ) (2 ) Foreign currency translation (5 ) (3 ) Balance as of December 31 $ 119 $ 123 (a) Changes in estimated cash flows for the year ended December 31, 2014 includes changes in estimates primarily for our gypsum quarry and ship loading facility in Windsor, Nova Scotia, Canada, which we permanently closed during the third quarter of 2011, and our mining operation in Little Narrows, Nova Scotia, Canada as a result of receiving regulatory approval of a revised reclamation plan in 2014.

Long-Lived Asset Impairment C41

Long-Lived Asset Impairment Charges (Tables)	12 Months Ended
	Dec. 31, 2015
Restructuring and Related Activities [Abstract]
Schedule of impairment charges	In 2014, we recorded the following impairment charges: (millions) 2014 Ocean vessels $ 60 Wallboard lines or facilities 16 Previously incurred costs related to construction of future facilities 12 Other 2 Total long-lived asset impairment charges $ 90

Segments (Tables)

Segments (Tables)	12 Months Ended
	Dec. 31, 2015
Segment Reporting [Abstract]
Schedule of reportable segment results	Segment results were as follows: GYPSUM, CEILINGS AND DISTRIBUTION For the year ended December 31, (millions) 2015 2014 2013 Net Sales: Gypsum $ 2,397 $ 2,403 $ 2,262 Ceilings 499 513 568 Distribution 1,428 1,345 1,245 Eliminations (548 ) (537 ) (505 ) Total $ 3,776 $ 3,724 $ 3,570 Operating Profit (Loss): Gypsum $ 348 $ 169 $ 261 Ceilings 89 87 98 Distribution 27 16 6 Corporate (95 ) (109 ) (93 ) Eliminations 12 (1 ) (14 ) Total $ 381 $ 162 $ 258 Depreciation, Depletion and Amortization: Gypsum $ 106 $ 116 $ 115 Ceilings 16 14 14 Distribution 11 12 12 Corporate 9 12 14 Total $ 142 $ 154 $ 155 Capital Expenditures: Gypsum $ 86 $ 96 $ 66 Ceilings 3 30 54 Distribution 5 5 3 Corporate — 1 1 Total $ 94 $ 132 $ 124 Assets: December 31, 2015 December 31, 2014 Gypsum $ 1,991 $ 2,106 Ceilings 276 285 Distribution 376 412 Corporate 1,487 489 Equity method investments 682 735 Eliminations (76 ) (91 ) Total $ 4,736 $ 3,936
Schedule of geographic information	GEOGRAPHIC INFORMATION For the year ended December 31, (millions) 2015 2014 2013 Net Sales: United States $ 3,387 $ 3,220 $ 3,029 Canada 379 406 417 Other Foreign 196 283 309 Geographic transfers (186 ) (185 ) (185 ) Total $ 3,776 $ 3,724 $ 3,570 Long-lived assets, consisting of property, plant and equipment, net, by geographic location were as follows: (millions) December 31, December 31, Long-Lived Assets: United States $ 1,622 $ 1,665 Canada 90 112 Other Foreign 76 131 Total $ 1,788 $ 1,908
UBBP Reporting	UBBP For the year ended December 31, (millions) 2015 2014 (a) Net sales $ 1,003 $ 927 Operating profit 124 95 Net income attributable to UBBP 96 67 Depreciation, depletion, and amortization 43 31 Capital expenditures 49 40 December 31, 2015 December 31, 2014 Assets $ 1,303 $ 1,435 UBBP GEOGRAPHIC INFORMATION For the year ended December 31, (millions) 2015 2014 (a) Net Sales: Australia $ 345 $ 312 South Korea 200 197 China 120 122 Thailand 145 133 Other 234 206 Geographic Transfers (41 ) (43 ) Total $ 1,003 $ 927 (a) Operating results are presented for UBBP for the ten months ended December 31, 2014 . Long-lived assets, consisting of property, plant and equipment, net, by geographic location for UBBP were as follows: (millions) December 31, 2015 December 31, 2014 Long-Lived Assets: Australia $ 216 $ 245 South Korea 106 113 China 116 127 Oman 103 96 Thailand 72 72 Other 67 78 Total $ 680 $ 731

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Schedule of income from continuing operations before income taxes	Income from continuing operations before income taxes consisted of the following: (millions) 2015 2014 2013 U.S. $ 178 $ 27 $ 17 Foreign 84 19 42 Total $ 262 $ 46 $ 59
Schedule of income tax expense (benefit) on continuing operations	Income tax expense (benefit) on continuing operations consisted of the following: (millions) 2015 2014 2013 Current: Federal $ — $ — $ — Foreign 12 2 10 State 1 1 1 13 3 11 Deferred: Federal (621 ) — (2 ) Foreign (4 ) 4 2 State (117 ) — — (742 ) 4 — Total $ (729 ) $ 7 $ 11
Schedule of differences between actual provisions for income taxes and provisions for income taxes at the U.S. federal statutory rate	For our continuing operations, differences between actual provisions for income taxes and provisions for income taxes at the U.S. federal statutory rate ( 35% ) were as follows: (millions) 2015 2014 2013 Taxes on income from continuing operations at U.S. federal statutory rate $ 92 $ 16 $ 21 Foreign earnings subject to different tax rates (a) (3 ) 16 (6 ) State income tax, net of federal benefit 9 1 1 Change in valuation allowance (827 ) (9 ) (8 ) Income from equity method investments (b) (16 ) (12 ) — Withholding taxes — 2 6 Other, net 2 (1 ) (3 ) Tax release from AOCI — (2 ) — Gain on deconsolidation — (7 ) — Benefits from unrecognized tax positions (6 ) — — Tax benefit not realized on pension loss — 3 — Tax on distribution of foreign earnings 20 — — Provision for income tax expense $ (729 ) $ 7 $ 11 Effective income tax rate (277.7 )% 15.3 % 18.6 % (a) Foreign earnings subject to different tax rates includes amounts related to impairments and other charges associated with our GTL business. (b) Included in income from equity method investments are taxes associated with that income. These taxes, which are predominately foreign statutory rates, are at rates that are lower than the U.S. federal statutory rate.
Schedule of components of deferred tax assets and liabilities	Significant components of deferred tax assets and liabilities as of December 31 were as follows: (millions) 2015 2014 Deferred Tax Assets: Net operating loss and tax credit carryforwards $ 779 $ 944 Pension and postretirement benefits 150 196 Goodwill and other intangible assets 24 29 Reserves not deductible until paid 29 47 Self insurance 11 15 Capitalized interest 13 15 Inventories 8 8 Share-based compensation 33 37 Other 5 11 Deferred tax assets before valuation allowance 1,052 1,302 Valuation allowance (75 ) (1,023 ) Total deferred tax assets $ 977 $ 279 Deferred Tax Liabilities: Property, plant and equipment 254 278 Other — — Total deferred tax liabilities 254 278 Net deferred tax assets $ 723 $ 1
Reconciliation of the beginning and ending amount of unrecognized tax benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: (millions) 2015 2014 2013 Balance as of January 1 $ 22 $ 22 $ 16 Tax positions related to the current period: Gross increase 4 2 4 Gross decrease — — — Tax positions related to prior periods: Gross increase — — 2 Gross decrease (1 ) — — Settlements (6 ) (2 ) — Lapse of statutes of limitations (1 ) — — Balance as of December 31 $ 18 $ 22 $ 22

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Reconciliation of basic income per share to diluted income per share	The reconciliation of basic income per share to diluted income per share is shown in the following table: (millions, except per-share data) 2015 2014 2013 Income from continuing operations $ 991 $ 39 $ 48 Net income (loss) attributable to noncontrolling interest — 1 $ (1 ) Income from continuing operations attributable to USG $ 991 $ 38 $ 49 Loss from discontinued operations — (1 ) (2 ) Net income attributable to USG $ 991 $ 37 $ 47 Effect of dilutive securities - Deferred compensation program for non-employee directors (1 ) — — Income available to shareholders $ 990 $ 37 $ 47 Average common shares 145.5 141.7 108.9 Dilutive RSUs, MSUs, performance shares and stock options 1.6 2.4 2.5 Deferred shares associated with a deferred compensation program for non-employee directors 0.1 0.2 — Average diluted common shares 147.2 144.3 111.4 Basic earnings (loss) per average common share: Income from continuing operations attributable to USG $ 6.81 $ 0.27 $ 0.45 Loss from discontinued operations — (0.01 ) (0.02 ) Net income attributable to USG $ 6.81 $ 0.26 $ 0.43 Diluted earnings (loss) per average common share: Income from continuing operations attributable to USG $ 6.73 $ 0.26 $ 0.44 Loss from discontinued operations — (0.01 ) (0.02 ) Net income attributable to USG $ 6.73 $ 0.25 $ 0.42
Schedule of ant-dilutive securities excluded from computation of diluted earnings (loss) per share	Stock options, RSUs, MSUs, performance shares, common shares issuable upon conversion of our 10% convertible senior notes and deferred shares associated with our deferred compensation program for non-employee directors that were not included in the computation of diluted earnings (loss) per share for those periods because their inclusion was anti-dilutive were as follows: (millions, common shares) 2015 2014 2013 Stock options, RSUs, MSUs and performance shares 1.9 2.1 2.2 10% convertible senior notes due 2018 (a) — — 6.6 Deferred shares associated with a deferred compensation program for non-employee directors — — 0.2 (a) In December 2013 and April 2014, we converted $ 325 million and $75 million , respectively, of our 10% convertible senior notes due 2018 into common shares.

Lease Commitments Lease Commitm

Lease Commitments Lease Commitments (Tables)	12 Months Ended
	Dec. 31, 2015
Lease Commitments [Abstract]
Schedule of future minimum lease payments required under operating leases	Future minimum lease payments required under operating leases with initial or remaining noncancelable terms in excess of one year as of December 31, 2015 were as follows: (millions) 2016 2017 2018 2019 2020 After 2020 Future minimum lease payments $ 72 $ 65 $ 53 $ 40 $ 26 $ 32

Quarterly Financial Data (una46

Quarterly Financial Data (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Schedule of quarterly financial information	Quarter (millions, except per-share data) First Second Third Fourth 2015 Net sales $ 909 $ 970 $ 972 $ 925 Gross profit 153 183 183 172 Operating profit 76 105 102 98 Income from continuing operations (b) 24 79 76 812 Loss from discontinued operations, net of tax — — — — Net income attributable to USG (b) 24 79 76 812 Income from continuing operations per common share: Basic (a) 0.16 0.54 0.52 5.58 Diluted (a) 0.16 0.54 0.52 5.51 2014 Net sales $ 850 $ 948 $ 972 $ 954 Gross profit 143 175 176 160 Operating profit (loss) (c) 66 98 22 (24 ) Income (loss) from continuing operations (c) 45 58 (11 ) (53 ) Loss from discontinued operations, net of tax — (1 ) — — Net income (loss) attributable to USG (c) 45 57 (12 ) (53 ) Income (loss) from continuing operations per common share: Basic (a) 0.33 0.40 (0.09 ) (0.36 ) Diluted (a) 0.32 0.39 (0.09 ) (0.36 ) (a) The sum of the four quarters is not necessarily the same as the total for the year. (b) Income from continuing operations and net income attributable to USG for the fourth quarter of 2015 included a reversal of an income tax valuation allowance of $731 million . (c) Operating profit (loss), income (loss) from continuing operations, and net income (loss) attributable to USG for the third quarter of 2014 included a litigation settlement charge of $48 million and long-lived asset impairment charges of $30 million and for the fourth quarter of 2014 included a long-lived asset impairment charge of $60 million , contract termination charge and loss of receivable of $15 million , and pension settlement charges of $13 million .

Significant Accounting Polici47

Significant Accounting Policies - Consolidation and Presentation (Details)	Dec. 31, 2015	Dec. 31, 2014	Feb. 27, 2014
Knauf USG
Schedule of Equity Method Investments [Line Items]
Ownership percentage interest	50.00%
USG Boral Building Products
Schedule of Equity Method Investments [Line Items]
Ownership percentage interest	50.00%	50.00%	50.00%
USG Boral Building Products | Co-venturer
Schedule of Equity Method Investments [Line Items]
Ownership percentage by joint venture partner			50.00%
Minimum
Schedule of Equity Method Investments [Line Items]
Ownership percentage interest	20.00%
Maximum
Schedule of Equity Method Investments [Line Items]
Ownership percentage interest	50.00%

Significant Accounting Polici48

Significant Accounting Policies - Advertising (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accounting Policies [Abstract]
Advertising expense	$ 17	$ 23	$ 22

Significant Accounting Polici49

Significant Accounting Policies - Research and Development (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accounting Policies [Abstract]
Research and development expenditures	$ 23	$ 23	$ 21

Significant Accounting Polici50

Significant Accounting Policies - Earnings per Share (Details)	Dec. 31, 2015
10% convertible senior notes due 2018
Debt Instrument [Line Items]
Interest rate of convertible senior notes	10.00%

Significant Accounting Polici51

Significant Accounting Policies - Property, Plant and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Capitalized interest	$ 3	$ 3	$ 3
Buildings and improvements
Property, Plant and Equipment [Line Items]
Expected useful life	50 years
Machinery and equipment | Minimum
Property, Plant and Equipment [Line Items]
Expected useful life	10 years
Machinery and equipment | Maximum
Property, Plant and Equipment [Line Items]
Expected useful life	25 years
Computer software and systems development costs | Minimum
Property, Plant and Equipment [Line Items]
Expected useful life	5 years
Computer software and systems development costs | Maximum
Property, Plant and Equipment [Line Items]
Expected useful life	7 years

Significant Accounting Polici52

Significant Accounting Policies - Intangible Assets (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Accounting Policies [Abstract]
Assets classified as held for sale	$ 0	$ 5

Significant Accounting Polici53

Significant Accounting Policies - Derivative Instruments (Details)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Typical hedging period	3 years
Period of anticipated natural gas purchases typically hedged	12 months

Significant Accounting Polici54

Significant Accounting Policies - Foreign Currency Translation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accounting Policies [Abstract]
Transaction loss	$ 7	$ 6	$ 4

Recent Accounting Pronounceme55

Recent Accounting Pronouncements Recent Accounting Pronouncements (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt issuance cost	$ 13	$ 14
Accounting Standards Update 2015 17
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred tax asset reclassification, current assets to long term assets		1
Deferred tax asset reclassification, current assets to long term liabilities		44
Accounting Standards Update 2015 03
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt issuance cost		$ 14

Equity Method Investments - Sch

Equity Method Investments - Schedule of Investments (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Feb. 27, 2014
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 682	$ 735
Minimum
Schedule of Equity Method Investments [Line Items]
Ownership percentage interest	20.00%
Maximum
Schedule of Equity Method Investments [Line Items]
Ownership percentage interest	50.00%
USG Boral Building Products
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 675	$ 689	$ 676
Ownership percentage interest	50.00%	50.00%	50.00%
Other equity method investments
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 7	$ 46
Other equity method investments | Minimum
Schedule of Equity Method Investments [Line Items]
Ownership percentage interest	33.00%	33.00%
Other equity method investments | Maximum
Schedule of Equity Method Investments [Line Items]
Ownership percentage interest	50.00%	50.00%
Knauf USG
Schedule of Equity Method Investments [Line Items]
Equity method investments		$ 38
Ownership percentage interest	50.00%

Equity Method Investments - Tex

Equity Method Investments - Textuals (Details) € in Millions	Dec. 22, 2015USD ($)	Feb. 27, 2014USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	Sep. 15, 2015USD ($)	Sep. 15, 2015EUR (€)	Oct. 31, 2013USD ($)
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments		$ 515,000,000
Long-term debt			$ 2,188,000,000	$ 2,209,000,000
Present value of contingent liability for contingent consideration for equity method investment			24,000,000	23,000,000
Equity method investments			682,000,000	735,000,000
Gain on deconsolidation of subsidiaries and consolidated joint ventures			0	27,000,000	$ 0
Gain on revaluation of retained investment on deconsolidation				$ 11,000,000
Weighted average discount rate				11.00%
Weighted average long-term growth rate				2.00%
Translation loss			(67,000,000)	$ (68,000,000)	(17,000,000)
Cash dividends paid			38,000,000	0	0
Expected purchase price of joint venture						$ 52,000,000	€ 48
Income taxes payable on sale	$ 5,000,000
Income and gain from the sale of equity method investment to related party			13,000,000	2,000,000	2,000,000
5.875% senior notes due 2021
Schedule of Equity Method Investments [Line Items]
Long-term debt			$ 350,000,000	$ 350,000,000				$ 350,000,000
Interest rate of convertible senior notes			5.875%	5.875%				5.875%
Base purchase price
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments		500,000,000
Adjustments to purchase price
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments		$ 15,000,000
Knauf
Schedule of Equity Method Investments [Line Items]
Percentage of beneficial ownership of affiliates			10.00%
USG Boral Building Products
Schedule of Equity Method Investments [Line Items]
Ownership percentage interest		50.00%	50.00%	50.00%
Contingent consideration amount (up to)		$ 75,000,000
Contingent consideration for first performance period		$ 25,000,000
First performance period for contingent consideration		3 years
Contingent consideration for second performance period (up to)		$ 50,000,000
Second performance period for contingent consideration		5 years
Equity method investments		$ 676,000,000	$ 675,000,000	$ 689,000,000
Translation loss			(23,000,000)	(34,000,000)	0
Cash dividends paid			38,000,000
Consolidated retained earnings which represents undistributed earnings			$ 42,000,000
USG Boral Building Products | Boral
Schedule of Equity Method Investments [Line Items]
Ownership percentage by joint venture partner		50.00%
Knauf USG
Schedule of Equity Method Investments [Line Items]
Ownership percentage interest			50.00%
Equity method investments				38,000,000
Gain on sale of investment	$ 6,000,000
Income and gain from the sale of equity method investment to related party			$ 13,000,000	$ 2,000,000	$ 2,000,000

Equity Method Investments - Sta

Equity Method Investments - Statement of Operations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments	$ 50	$ 35	$ 1
USG Boral Building Products
Schedule of Equity Method Investments [Line Items]
Net sales	1,003	927
Gross profit	278	251
Operating profit	124	95
Net income from continuing operations	101	72
Net income	101	72
Net income attributable to USG Boral Building Products	96	67
Income (loss) from equity method investments	48	33
Other equity method investments
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments	$ 2	$ 2	$ 1

Equity Method Investments - Bal

Equity Method Investments - Balance Sheet (Details) - USG Boral Building Products - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Current assets	$ 368	$ 446
Non-current assets	935	989
Current liabilities	197	245
Long-term debt	40	46
Other non-current liabilities	17	21
Shareholders' equity	1,049	1,123
Current portion of long-term debt	16	35
Shareholders' equity related to non-controlling interests	$ 60	$ 70

Marketable Securities - Investm

Marketable Securities - Investments in Marketable Securities (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 230	$ 154
Fair Value	230	154
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	134	93
Fair Value	134	93
U.S. government and agency debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	57	22
Fair Value	57	22
Asset-backed debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	21	17
Fair Value	21	17
Certificates of deposit
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	15	18
Fair Value	15	18
Municipal debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3	4
Fair Value	$ 3	$ 4

Marketable Securities - Contrac

Marketable Securities - Contractual Maturities of Marketable Securities (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Amortized Cost
Due in 1 year or less	$ 194
Due in 1-5 years	36
Total marketable securities	230
Fair Value
Due in 1 year or less	194
Due in 1-5 years	36
Total marketable securities	$ 230	$ 154

Intangible Assets - Intangible

Intangible Assets - Intangible Assets with Definite Lives (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Intangible Assets with Definite Lives:
Gross Carrying Amount	$ 79	$ 79
Accumulated Amortization	(69)	(61)
Net	10	18
Customer relationships
Intangible Assets with Definite Lives:
Gross Carrying Amount	70	70
Accumulated Amortization	(61)	(54)
Net	9	16
Other
Intangible Assets with Definite Lives:
Gross Carrying Amount	9	9
Accumulated Amortization	(8)	(7)
Net	$ 1	$ 2

Intangible Assets - Textuals (D

Intangible Assets - Textuals (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Intangible Assets with Definite Lives:
Amortization expense	$ 8	$ 7	$ 7
Assets classified as held for sale	$ 0	$ 5
Customer relationships
Intangible Assets with Definite Lives:
Weighted average amortization period	10 years
Other
Intangible Assets with Definite Lives:
Weighted average amortization period	11 years

Intangible Assets - Estimated A

Intangible Assets - Estimated Annual Amortization Expense (Details) $ in Millions	Dec. 31, 2015USD ($)
Estimated annual amortization expense
2,016	$ 7
2,017	2
2018 and thereafter	$ 1

Intangible Assets - Intangibl65

Intangible Assets - Intangible Assets with Indefinite Lives (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Indefinite-lived Intangible Assets [Line Items]
Gross carrying amount	$ 30	$ 30
Trade names
Indefinite-lived Intangible Assets [Line Items]
Gross carrying amount	22	22
Other
Indefinite-lived Intangible Assets [Line Items]
Gross carrying amount	$ 8	$ 8

Debt - Total Debt (Details)

Debt - Total Debt (Details) - USD ($) $ in Millions	Dec. 31, 2015	Feb. 24, 2015	Dec. 31, 2014	Oct. 31, 2013
Debt Instrument [Line Items]
Long-term debt	$ 2,188		$ 2,209
Less unamortized debt issuance costs	13		14
Total	2,175		2,195
Current portion of long-term debt	500		4
5.5% senior notes due 2025
Debt Instrument [Line Items]
Long-term debt	350		$ 0
Less unamortized debt issuance costs		$ 6
Total	$ 344
Stated interest rate	5.50%		5.50%
5.875% senior notes due 2021
Debt Instrument [Line Items]
Long-term debt	$ 350		$ 350	$ 350
Stated interest rate	5.875%		5.875%	5.875%
6.3% senior notes due 2016
Debt Instrument [Line Items]
Long-term debt	$ 500		$ 500
Stated interest rate	6.30%		6.30%
7.75% senior notes due 2018
Debt Instrument [Line Items]
Long-term debt	$ 500		$ 500
Stated interest rate	7.75%		7.75%
7.875% senior notes due 2020 (net of discount: 2015 - $1; 2014 - $1)
Debt Instrument [Line Items]
Long-term debt	$ 249		$ 249
Stated interest rate	7.875%		7.875%
Unamortized discount	$ 1		$ 1
8.375% senior notes due 2018
Debt Instrument [Line Items]
Long-term debt	$ 0		$ 350
Stated interest rate	8.375%		8.375%
Ship mortgage facility (includes current portion of long-term debt: 2015 - $0; 2014 - $4)
Debt Instrument [Line Items]
Long-term debt	$ 0		$ 21
Current portion of long-term debt	0		4
Industrial revenue bonds (due 2028 through 2034)
Debt Instrument [Line Items]
Long-term debt	$ 239		$ 239

Debt - Repurchase of 8.375% Sen

Debt - Repurchase of 8.375% Senior Notes and Issuance of 5.5% Senior Notes (Details) - USD ($)	Mar. 26, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2015	Feb. 24, 2015
Debt Instrument [Line Items]
Loss on early extinguishment of debt	$ 19,000,000	$ 19,000,000	$ 0	$ 0
Debt issuance cost		13,000,000	14,000,000
Amount of debt outstanding		2,188,000,000	2,209,000,000
Long Term Debt, Net Of Unamortized Debt Issuance Costs		$ 2,175,000,000	$ 2,195,000,000
8.375% senior notes due 2018
Debt Instrument [Line Items]
Stated interest rate		8.375%	8.375%
Repurchase amount	224,000,000				$ 350,000,000	$ 126,000,000
Aggregate consideration	$ 242,000,000					135,000,000
Amount of debt outstanding		$ 0	$ 350,000,000
5.5% senior notes due 2025
Debt Instrument [Line Items]
Stated interest rate		5.50%	5.50%
Face amount of notes						350,000,000
Debt issuance cost						$ 6,000,000
Amount of debt outstanding		$ 350,000,000	$ 0
Long Term Debt, Net Of Unamortized Debt Issuance Costs		$ 344,000,000

Debt - Senior Notes (Details)

Debt - Senior Notes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Oct. 31, 2013
Debt Instrument [Line Items]
Amount of debt outstanding	$ 2,188	$ 2,209
6.3% senior notes due 2016
Debt Instrument [Line Items]
Stated interest rate	6.30%	6.30%
Amount of debt outstanding	$ 500	$ 500
Percentage of purchase price of notes at their principal amount	101.00%
Percentage of principal amount of the notes being redeemed	100.00%
7.75% senior notes due 2018
Debt Instrument [Line Items]
Stated interest rate	7.75%	7.75%
Amount of debt outstanding	$ 500	$ 500
Percentage of purchase price of notes at their principal amount	101.00%
Percentage of principal amount of the notes being redeemed	100.00%
Effective interest rate	9.75%
7.75% senior notes due 2018 | Maximum
Debt Instrument [Line Items]
Interest rate adjustment (as a percent)	2.00%
5.5% senior notes due 2025
Debt Instrument [Line Items]
Stated interest rate	5.50%	5.50%
Amount of debt outstanding	$ 350	$ 0
Percentage of purchase price of notes at their principal amount	101.00%
Percentage of principal amount of the notes being redeemed	100.00%
7.875% senior notes due 2020
Debt Instrument [Line Items]
Stated interest rate	7.875%	7.875%
Amount of debt outstanding	$ 249	$ 249
Percentage of purchase price of notes at their principal amount	101.00%
Percentage of principal amount of the notes being redeemed	100.00%
5.875% senior notes due 2021
Debt Instrument [Line Items]
Stated interest rate	5.875%	5.875%	5.875%
Amount of debt outstanding	$ 350	$ 350	$ 350
Percentage of purchase price of notes at their principal amount	101.00%
Percentage of principal amount of the notes being redeemed	100.00%

Debt - Credit Facility (Details

Debt - Credit Facility (Details) CAD in Millions	Dec. 31, 2015CAD	Dec. 31, 2015USD ($)
Line of credit
Line of Credit Facility [Line Items]
Maximum borrowing limit		$ 450,000,000
Current borrowing capacity		295,000,000
Maximum allowable borrowings		650,000,000
Borrowings available under credit facility		$ 0
Applicable interest rate	1.86%	1.86%
Letters of credit outstanding		$ 49,000,000
Line of credit | CGC, Inc.
Line of Credit Facility [Line Items]
Maximum borrowing limit		50,000,000
Letter of credit
Line of Credit Facility [Line Items]
Maximum borrowing limit		200,000,000
CGC USD
Line of Credit Facility [Line Items]
Current borrowing capacity		$ 50,000,000
CGC CAD
Line of Credit Facility [Line Items]
Applicable interest rate	2.12%	2.12%
Letters of credit outstanding | CAD	CAD 1

Debt - Industrial Revenue Bonds

Debt - Industrial Revenue Bonds (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Line of Credit Facility [Line Items]
Amount of debt outstanding	$ 2,188	$ 2,209
Industrial revenue bonds
Line of Credit Facility [Line Items]
Amount of debt outstanding	$ 239	$ 239
Minimum fixed interest rate	5.50%
Maximum fixed interest rate	6.40%
Weighted average interest rate	5.875%

Debt - Other Information (Detai

Debt - Other Information (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Debt Disclosure [Abstract]
Fair value of debt	$ 2,295	$ 2,338
Interest accrued on debt	45	$ 45
Debt maturities (principal amounts)
2,016	500
2,017	0
2,018	500
2,019	0
2,020	250
After 2,020	$ 939

Derivative Instruments - Textua

Derivative Instruments - Textuals (Details) MMBTU in Millions	Dec. 22, 2015USD ($)	Dec. 31, 2015USD ($)MMBTU	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	Sep. 30, 2015USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Net liability position of derivatives		$ 13,000,000
Collateral provided to counterparties related to derivatives		$ 21,000,000
Commodity contracts
Derivative Instruments, Gain (Loss) [Line Items]
Aggregate notional amount | MMBTU		22
Ineffectiveness recorded on contracts		$ 0	$ 0	$ 0
Unrealized loss		2,000,000	5,000,000
Commodity contracts | Derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain (loss) remaining in AOCI		(19,000,000)	(20,000,000)
Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain reclassified from AOCI to earnings	$ 1,000,000
Foreign exchange contracts | Derivatives in Cash Flow Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Ineffectiveness recorded on contracts		0	0	$ 0
Notional amounts of foreign exchange forward contracts		114,000,000
Foreign exchange contracts | Derivatives in Net Investment Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Notional amounts of foreign exchange forward contracts					$ 35,000,000
Foreign exchange contracts | Derivatives | Derivatives in Cash Flow Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain (loss) remaining in AOCI		$ 8,000,000	$ 3,000,000

Derivative Instruments - Pretax

Derivative Instruments - Pretax Effects of Derivative Instruments (Details) - USD ($) $ in Millions	Dec. 22, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)	$ 1
Derivatives Designated as Hedging Instruments | Derivatives in Cash Flow Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on Derivatives (Effective Portion)		$ (1)	$ (15)	$ 4
Amount of Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)		(7)	4	1
Derivatives Designated as Hedging Instruments | Commodity contracts | Derivatives in Cash Flow Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on Derivatives (Effective Portion)		(14)	(19)	1
Derivatives Designated as Hedging Instruments | Commodity contracts | Cost of products sold | Derivatives in Cash Flow Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)		(15)	2	(2)
Derivatives Designated as Hedging Instruments | Foreign exchange contracts | Derivatives in Cash Flow Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on Derivatives (Effective Portion)		12	4	3
Derivatives Designated as Hedging Instruments | Foreign exchange contracts | Derivatives in Net Investment Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on Derivatives (Effective Portion)		1	0	0
Derivatives Designated as Hedging Instruments | Foreign exchange contracts | Cost of products sold | Derivatives in Cash Flow Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)		7	2	3
Derivatives Designated as Hedging Instruments | Foreign exchange contracts | Income and gain from the sale of equity method investment to related party | Derivatives in Net Investment Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)		1	0	0
Derivatives Not Designated as Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Income on Derivatives		(1)	(4)	2
Derivatives Not Designated as Hedging Instruments | Commodity contracts | Cost of products sold
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Income on Derivatives		(3)	(4)	2
Derivatives Not Designated as Hedging Instruments | Foreign exchange contracts | Other (income) expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Income on Derivatives		$ 2	$ 0	$ 0

Derivative Instruments - Fair V

Derivative Instruments - Fair Values of Derivative Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Fair values of derivative instruments on the consolidated balance sheets
Total assets	$ 9	$ 4
Total liabilities	22	26
Derivatives Not Designated as Hedging Instruments
Fair values of derivative instruments on the consolidated balance sheets
Total assets	0	0
Total liabilities	2	5
Commodity contracts | Other current assets | Derivatives Not Designated as Hedging Instruments
Fair values of derivative instruments on the consolidated balance sheets
Total assets	0	0
Commodity contracts | Other assets | Derivatives Not Designated as Hedging Instruments
Fair values of derivative instruments on the consolidated balance sheets
Total assets	0	0
Commodity contracts | Accrued expenses | Derivatives Not Designated as Hedging Instruments
Fair values of derivative instruments on the consolidated balance sheets
Total liabilities	2	4
Commodity contracts | Other liabilities | Derivatives Not Designated as Hedging Instruments
Fair values of derivative instruments on the consolidated balance sheets
Total liabilities	0	1
Derivatives in Cash Flow Hedging Relationships | Derivatives in Cash Flow Hedging Relationships
Fair values of derivative instruments on the consolidated balance sheets
Total assets	9	4
Total liabilities	20	21
Derivatives in Cash Flow Hedging Relationships | Commodity contracts | Other current assets | Derivatives in Cash Flow Hedging Relationships
Fair values of derivative instruments on the consolidated balance sheets
Total assets	1	1
Derivatives in Cash Flow Hedging Relationships | Commodity contracts | Other assets | Derivatives in Cash Flow Hedging Relationships
Fair values of derivative instruments on the consolidated balance sheets
Total assets	0	0
Derivatives in Cash Flow Hedging Relationships | Commodity contracts | Accrued expenses | Derivatives in Cash Flow Hedging Relationships
Fair values of derivative instruments on the consolidated balance sheets
Total liabilities	15	14
Derivatives in Cash Flow Hedging Relationships | Commodity contracts | Other liabilities | Derivatives in Cash Flow Hedging Relationships
Fair values of derivative instruments on the consolidated balance sheets
Total liabilities	5	7
Derivatives in Cash Flow Hedging Relationships | Foreign exchange contracts | Other current assets | Derivatives in Cash Flow Hedging Relationships
Fair values of derivative instruments on the consolidated balance sheets
Total assets	8	3
Derivatives in Cash Flow Hedging Relationships | Foreign exchange contracts | Accrued expenses | Derivatives in Cash Flow Hedging Relationships
Fair values of derivative instruments on the consolidated balance sheets
Total liabilities	$ 0	$ 0

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 248	$ 125
Equity mutual funds	4	4
Marketable securities	230	154
Derivative assets	9	4
Derivative liabilities	(22)	(26)
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	134	93
U.S. government and agency debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	57	22
Asset-backed debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	21	17
Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	15	18
Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	3	4
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	223	93
Equity mutual funds	4	4
Derivative assets	0	0
Derivative liabilities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. government and agency debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Asset-backed debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	25	32
Equity mutual funds	0	0
Derivative assets	9	4
Derivative liabilities	(22)	(26)
Significant Other Observable Inputs (Level 2) | Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	134	93
Significant Other Observable Inputs (Level 2) | U.S. government and agency debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	57	22
Significant Other Observable Inputs (Level 2) | Asset-backed debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	21	17
Significant Other Observable Inputs (Level 2) | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	15	18
Significant Other Observable Inputs (Level 2) | Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	3	4
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Equity mutual funds	0	0
Derivative assets	0	0
Derivative liabilities	0	0
Significant Unobservable Inputs (Level 3) | Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Significant Unobservable Inputs (Level 3) | U.S. government and agency debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Significant Unobservable Inputs (Level 3) | Asset-backed debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Significant Unobservable Inputs (Level 3) | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Significant Unobservable Inputs (Level 3) | Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	$ 0	$ 0

Fair Value Measurements - Textu

Fair Value Measurements - Textuals (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived asset impairment charges		$ 30	$ 0	$ 90	$ 0
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived asset impairment charges				30
Self-unloading ocean vessels
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived asset impairment charges	$ 60			$ 60

Employee Retirement Plans - Tex

Employee Retirement Plans - Textuals (Details) - USD ($) $ in Millions	Jan. 01, 2014	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation			$ 1,354	$ 1,429
Minimum funded percentage of ABO			100.00%
Defined Contribution Plans Disclosure [Abstract]
Total charges for defined contribution plans			$ 7	6	$ 3
Minimum contribution percentage			1.00%
Maximum contribution percentage			75.00%
Employees earned a guaranteed company on contributions (as a percent)	25.00%				10.00%
Employees earned a guaranteed company match on eligible compensation (up to) (as a percent)	6.00%				6.00%
Vested period company matching contributions for employee			3 years
USG Corporation Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Settlement charge		$ 15
Pension
Defined Benefit Plan Disclosure [Line Items]
Settlement charge			$ 1	13	$ 16
Actuarial gain			$ 119	$ (327)
Weighted-average discount rate		4.90%	4.43%	4.10%	4.90%
Net actuarial loss			$ 19
Prior service cost (credit)			$ 0
Expected return on plan assets (as a percent)			6.70%	7.00%
Estimated future employer benefit plan contribution			$ 65
Expected future benefit payments in next twelve months			105
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Actuarial gain			$ 14	$ (4)
Weighted-average discount rate			4.24%	3.70%
Net actuarial loss			$ 1
Prior service cost (credit)			(28)
Expected future benefit payments in next twelve months			$ 9
U.S. Postretirement Health Care Plan
Defined Benefit Plan Disclosure [Line Items]
Annual increase to contributions health care cost (as a percent)			3.00%
Canadian Postretirement Health Care Plan
Defined Benefit Plan Disclosure [Line Items]
Assumed health care cost trend rate			8.00%	8.25%
Ultimate health care cost trend rate			4.00%	4.00%

Employee Retirement Plans - Com

Employee Retirement Plans - Components of Net Pension and Postretirement Benefit Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost of benefits earned	$ 49	$ 37	$ 38
Interest cost on projected benefit obligation	66	65	63
Expected return on plan assets	(83)	(79)	(76)
Settlement	1	13	16
Net amortization	39	24	43
Net pension cost	72	60	84
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost of benefits earned	2	3	3
Interest cost on projected benefit obligation	6	7	7
Net amortization	(31)	(35)	(34)
Net pension cost	$ (23)	$ (25)	$ (24)

Employee Retirement Plans - Acc

Employee Retirement Plans - Accumulated Benefit Obligation (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Selected information for pension plans with accumulated benefit obligations in excess of plan assets:
Accumulated benefit obligation	$ (1,182)	$ (1,230)
Fair value of plan assets	1,097	1,113
Selected information for pension plans with benefit obligations in excess of plan assets:
Benefit obligation	(1,365)	(1,686)
Fair value of plan assets	$ 1,099	$ 1,340

Employee Retirement Plans - Pro

Employee Retirement Plans - Projected Benefit Obligations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Change in Plan Assets:
Fair value as of beginning of period	$ 1,340
Fair value as of end of period	1,301	$ 1,340
Components on the Consolidated Balance Sheets:
Current liabilities	(18)	(22)
Noncurrent liabilities	(392)	(491)
Pension
Change in Benefit Obligation:
Benefit obligation as of beginning of period	1,686	1,376
Service cost	49	37	$ 38
Interest cost	66	65	63
Curtailment/settlements	(4)	(24)
Participant contributions	11	10
Benefits paid	(86)	(81)
Plan amendment	0	0
Actuarial (gain) loss	(119)	327
Foreign currency translation	(39)	(24)
Benefit obligation as of end of period	1,564	1,686	1,376
Change in Plan Assets:
Fair value as of beginning of period	1,340	1,262
Actual return on plan assets	17	132
Employer contributions	61	64
Participant contributions	11	10
Benefits paid	(86)	(81)
Curtailment/settlements	(4)	(24)
Foreign currency translation	(38)	(23)
Fair value as of end of period	1,301	1,340	1,262
Funded status	(263)	(346)
Components on the Consolidated Balance Sheets:
Noncurrent assets	3	0
Current liabilities	(9)	(9)
Noncurrent liabilities	(257)	(337)
Net liability as of December 31	(263)	(346)
Pretax Components in AOCI:
Net actuarial loss	387	490
Prior service credit	(1)	(1)
Total as of end of year	386	489
Postretirement
Change in Benefit Obligation:
Benefit obligation as of beginning of period	167	166
Service cost	2	3	3
Interest cost	6	7	7
Curtailment/settlements	0	0
Participant contributions	3	8
Benefits paid	(11)	(20)
Plan amendment	0	4
Actuarial (gain) loss	(14)	4
Foreign currency translation	(9)	(5)
Benefit obligation as of end of period	144	167	166
Change in Plan Assets:
Fair value as of beginning of period	0	0
Actual return on plan assets	0	0
Employer contributions	8	12
Participant contributions	3	8
Benefits paid	(11)	(20)
Curtailment/settlements	0	0
Foreign currency translation	0	0
Fair value as of end of period	0	0	$ 0
Funded status	(144)	(167)
Components on the Consolidated Balance Sheets:
Noncurrent assets	0	0
Current liabilities	(9)	(13)
Noncurrent liabilities	(135)	(154)
Net liability as of December 31	(144)	(167)
Pretax Components in AOCI:
Net actuarial loss	7	24
Prior service credit	(108)	(140)
Total as of end of year	$ (101)	$ (116)

Employee Retirement Plans - Ass

Employee Retirement Plans - Assumptions (Details)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Pension
Weighted average assumptions used to determine benefit obligations as of December 31:
Discount rate	4.43%	4.10%	4.90%
Compensation increase rate	3.55%	3.60%
Weighted average assumptions used to determine net cost for years ended December 31:
Discount rate	4.10%	4.90%
Expected return on plan assets (as a percent)	6.70%	7.00%
Compensation increase rate	3.50%	3.50%
Postretirement
Weighted average assumptions used to determine benefit obligations as of December 31:
Discount rate	4.24%	3.70%
Weighted average assumptions used to determine net cost for years ended December 31:
Discount rate	3.70%	4.60%

Employee Retirement Plans - One

Employee Retirement Plans - One Percentage Point Change Effects (Details) $ in Millions	12 Months Ended
	Dec. 31, 2015USD ($)
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract]
Effect on total service and interest cost, one-percentage-point increase	$ 1
Effect on total service and interest cost, one-percentage-point decrease	0
Effect on postretirement benefit obligation, one-percentage-point increase	10
Effect on postretirement benefit obligation, one-percentage-point decrease	$ (8)

Employee Retirement Plans - Tar

Employee Retirement Plans - Target Asset Allocation and Acceptable Ranges (Details)	12 Months Ended
	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations (as a percent)	100.00%
Equity
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations (as a percent)	40.00%
Target plan asset allocations, range minimum (as a percent)	36.00%
Target plan asset allocations, range maximum (as a percent)	42.00%
Fixed income
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations (as a percent)	49.00%
Target plan asset allocations, range minimum (as a percent)	46.00%
Target plan asset allocations, range maximum (as a percent)	52.00%
Limited partnerships
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations (as a percent)	5.00%
Target plan asset allocations, range minimum (as a percent)	2.00%
Target plan asset allocations, range maximum (as a percent)	8.00%
Other real assets
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations (as a percent)	6.00%
Target plan asset allocations, range minimum (as a percent)	3.00%
Target plan asset allocations, range maximum (as a percent)	9.00%
Cash equivalents and short-term investments
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations (as a percent)	0.00%
Target plan asset allocations, range minimum (as a percent)	0.00%
Target plan asset allocations, range maximum (as a percent)	5.00%

Employee Retirement Plans - Fai

Employee Retirement Plans - Fair Values by Hierarchy of Inputs (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 1,301	$ 1,340
Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	144	139	$ 75
Common and preferred stock
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	55	74
Common and preferred stock | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	55	74
Common and preferred stock | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Common and preferred stock | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Commingled/pooled/mutual funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	502	523
Commingled/pooled/mutual funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	54	53
Commingled/pooled/mutual funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	448	470
Commingled/pooled/mutual funds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Total equity
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	557	597
Total equity | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	109	127
Total equity | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	448	470
Total equity | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. government and agency debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	177	195
U.S. government and agency debt securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. government and agency debt securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	177	195
U.S. government and agency debt securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. government and agency debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	32	30
Non-U.S. government and agency debt securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. government and agency debt securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	32	30
Non-U.S. government and agency debt securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Investment-grade debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	199	184
Investment-grade debt securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Investment-grade debt securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	199	184
Investment-grade debt securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
High-yield debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	36	39
High-yield debt securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
High-yield debt securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	36	39
High-yield debt securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Commingled/pooled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	129	114
Commingled/pooled funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Commingled/pooled funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	129	114
Commingled/pooled funds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4	9
Other | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Other | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	8
Other | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	1
Total fixed income
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	577	571
Total fixed income | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Total fixed income | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	576	570
Total fixed income | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	1	1
Limited partnerships
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	106	103
Limited partnerships | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Limited partnerships | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Limited partnerships | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	106	103	39
Other Real Estate Assets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	52	55
Other Real Estate Assets | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Other Real Estate Assets | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	15	20
Other Real Estate Assets | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	37	35	$ 35
Cash equivalents and short-term investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10	17
Cash equivalents and short-term investments | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash equivalents and short-term investments | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10	17
Cash equivalents and short-term investments | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,302	1,343
Total | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	109	127
Total | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,049	1,077
Total | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	144	139
Cash on hand
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Receivables
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	9	1
Accounts payable
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ (10)	$ (4)

Employee Retirement Plans - Rec

Employee Retirement Plans - Reconciliation of Change in Fair Value Measurement of Defined Benefit Plans' Consolidated Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Change in Plan Assets:
Fair value as of beginning of period	$ 1,340
Fair value as of end of period	1,301	$ 1,340
Significant Unobservable Inputs (Level 3)
Change in Plan Assets:
Fair value as of beginning of period	139	75
Realized gains	(1)	1
Unrealized gains (losses)	(6)	1
Purchases	2	67
Sales	(2)	(3)
Settlements	0	0
Net transfers into (out of) Level 3	0	0
Fair value as of end of period	144	139
Fixed income
Change in Plan Assets:
Fair value as of beginning of period	571
Fair value as of end of period	577	571
Fixed income | Significant Unobservable Inputs (Level 3)
Change in Plan Assets:
Fair value as of beginning of period	1	1
Realized gains	0	0
Unrealized gains (losses)	0	0
Purchases	0	0
Sales	0	0
Settlements	0	0
Net transfers into (out of) Level 3	0	0
Fair value as of end of period	1	1
Other Real Estate Assets
Change in Plan Assets:
Fair value as of beginning of period	55
Fair value as of end of period	52	55
Other Real Estate Assets | Significant Unobservable Inputs (Level 3)
Change in Plan Assets:
Fair value as of beginning of period	35	35
Realized gains	(1)	1
Unrealized gains (losses)	(5)	(1)
Purchases	0	0
Sales	(2)	(2)
Settlements	0	0
Net transfers into (out of) Level 3	0	0
Fair value as of end of period	37	35
Limited partnerships
Change in Plan Assets:
Fair value as of beginning of period	103
Fair value as of end of period	106	103
Limited partnerships | Significant Unobservable Inputs (Level 3)
Change in Plan Assets:
Fair value as of beginning of period	103	39
Realized gains	0	0
Unrealized gains (losses)	(1)	2
Purchases	2	67
Sales	0	(1)
Settlements	0	0
Net transfers into (out of) Level 3	0	0
Fair value as of end of period	$ 106	$ 103

Employee Retirement Plans - Exp

Employee Retirement Plans - Expected Benefit Payments (Details) $ in Millions	Dec. 31, 2015USD ($)
Pension Benefits
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
2,016	$ 105
2,017	84
2,018	94
2,019	95
2,020	128
2021 - 2025	585
Postretirement Benefits
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
2,016	9
2,017	9
2,018	10
2,019	10
2,020	8
2021 - 2025	$ 43

Share-Based Compensation - Text

Share-Based Compensation - Textuals (Details)	12 Months Ended
	Dec. 31, 2015USD ($)Installment$ / sharesshares	Dec. 31, 2014USD ($)$ / sharesshares	Dec. 31, 2013USD ($)$ / sharesshares	Dec. 31, 2012USD ($)
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of shares authorized for grants under the LTIP (in shares) | shares	12,700,000
Number of shares reserved for future grant under the LTIP (in shares) | shares	3,000,000
Expense for share-based arrangements	$ 15,000,000	$ 21,000,000	$ 19,000,000
Income tax benefits on share based arrangements	0	0	0
Share-based Compensation Awards
Operating loss carryforwards	1,755,000,000
Unrecognized tax benefits resulting in NOL carryforward	$ 18,000,000	$ 22,000,000	$ 22,000,000	$ 16,000,000
Non Employee Director Deferred Stock
Equity Instruments Other than Options, Additional Disclosures
Number of deferred stock units held by non-employee directors (in shares) | shares	193,117	164,235	182,632
Deferred stock unit expense	$ 1,000,000	$ 1,000,000	$ 1,000,000
Employee stock option
Share-based Compensation Awards
Excess tax benefit from option exercises	0	0	0
Operating loss carryforwards	68,000,000
Unrecognized tax benefits resulting in NOL carryforward	$ 24,000,000
Stock Options
Number of annual installments | Installment	4
Vesting period	1 year
Expiration period of stock options	10 years
Intrinsic value of stock options	$ 6,000,000	8,000,000	7,000,000
Cash received from exercise of stock options	6,000,000	4,000,000	4,000,000
Fair value of stock options vested	$ 1,000,000	$ 2,000,000	$ 10,000,000
MSUs
Stock Options
Vesting period	3 years
Equity Instruments Other than Options, Additional Disclosures
Weighted average grant date fair value of RSUs (in dollars per share) | $ / shares	$ 30.06	$ 40.20	$ 34.55
Minimum number of performance shares earned (as a percent)	0.00%
Maximum number of performance shares earned (as a percent)	150.00%
Awards vested (in shares) | shares	155,595
Number of shares vested | shares	119,808
Unrecognized compensation cost	$ 4,000,000
Weighted average period for recognition of unrecognized compensation cost	1 year 8 months 15 days
Number of shares granted | shares	474,000
RSUs
Stock Options
Vesting period	3 years
Equity Instruments Other than Options, Additional Disclosures
Weighted average grant date fair value of RSUs (in dollars per share) | $ / shares	$ 28.56	$ 32.50	$ 29.44
Awards vested (in shares) | shares	220,000
Unrecognized compensation cost	$ 3,000,000
Weighted average period for recognition of unrecognized compensation cost	2 years 7 months 6 days
Number of shares granted | shares	94,000
Fair value of RSUs that vested in period	$ 4,000,000	$ 6,000,000	$ 7,000,000
Performance shares
Stock Options
Vesting period	3 years
Equity Instruments Other than Options, Additional Disclosures
Weighted average grant date fair value of RSUs (in dollars per share) | $ / shares	$ 30.63	$ 46.46	$ 38.89
Minimum number of performance shares earned (as a percent)	0.00%
Maximum number of performance shares earned (as a percent)	200.00%
Awards vested (in shares) | shares	89,040
Number of shares vested | shares	0
Unrecognized compensation cost	$ 4,000,000
Weighted average period for recognition of unrecognized compensation cost	1 year 8 months
Number of shares granted | shares	147,000

Share-Based Compensation - Summ

Share-Based Compensation - Summary of Stock Options (Details) - Employee stock option - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Number of Options
Outstanding at beginning of period (in shares)	3,982
Exercised (in shares)	(410)
Canceled (in shares)	(67)
Forfeited (in shares)	(9)
Outstanding at end of period (in shares)	3,496	3,982
Exercisable (in shares)	3,363
Weighted Average Exercise Price
Outstanding at beginning of period (in dollars per share)	$ 26.77
Exercised (in dollars per share)	14.61
Canceled (in dollars per share)	41.50
Forfeited (in dollars per share)	14.76
Outstanding at end of period (in dollars per share)	28	$ 26.77
Exercisable (in dollars per share)	$ 28.51
Options Activity, Weighted Remaining Contractual Term and Aggregate Intrisic Value
Weighted Average Remaining Contractual Term, Outstanding	3 years 22 days	4 years 2 months 1 day
Weighted Average Remaining Contractual Term, Exercisable	2 years 11 months 5 days
Aggregate Intrinsic Value, Outstanding	$ 19	$ 31
Aggregate Intrinsic Value, Exercisable	$ 18
Vested or expected to vest
Number of Options	3,496
Weighted Average Exercise Price (in dollars per share)	$ 28
Weighted Average Remaining Contractual Term (years)	2 years 11 months 27 days
Aggregate Intrinsic Value	$ 19

Share-Based Compensation - MSUs

Share-Based Compensation - MSUs Assumptions (Details) - MSUs - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Assumptions:
Expected volatility (as a percent)	42.70%	54.93%	60.97%
Risk-free rate	1.09%	0.63%	0.35%
Expected term	2 years 11 months 13 days	2 years 11 months 10 days	2 years 4 months 18 days
Expected dividends	$ 0	$ 0	$ 0

Share-Based Compensation - MS90

Share-Based Compensation - MSUs Activity (Details) - MSUs - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Weighted Number of Shares
Nonvested at beginning of period (in shares)	511,000
Granted (in shares)	474,000
Vested (in shares)	(155,595)
Forfeited (in shares)	(86,000)
Nonvested at end of period (in shares)	743,000	511,000
Weighted Average Grant Date Fair Value
Nonvested at January 1 (in dollars per share)	$ 38.43
Granted (in dollars per share)	30.06	$ 40.20	$ 34.55
Vested (in dollars per share)	34.80
Forfeited (in dollars per share)	34.34
Nonvested at December 31 (in dollars per share)	$ 34.33	$ 38.43

Share-Based Compensation - RSUs

Share-Based Compensation - RSUs Activity (Details) - RSUs - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Number of Shares
Nonvested at beginning of period (in shares)	423
Granted (in shares)	94
Vested (in shares)	(220)
Forfeited (in shares)	(27)
Nonvested at end of period (in shares)	270	423
Weighted Average Grant Date Fair Value
Nonvested at January 1 (in dollars per share)	$ 20.12
Granted (in dollars per share)	28.56	$ 32.50	$ 29.44
Vested (in dollars per share)	17.84
Forfeited (in dollars per share)	24.36
Nonvested at December 31 (in dollars per share)	$ 24.49	$ 20.12

Share-Based Compensation - Perf

Share-Based Compensation - Performance Shares Assumptions (Details) - Performance shares - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Assumptions:
Expected volatility (as a percent)	42.70%	54.93%	59.98%
Risk-free rate	1.09%	0.63%	0.43%
Expected term	2 years 11 months 13 days	2 years 11 months 10 days	2 years 10 months 18 days
Expected dividends	$ 0	$ 0	$ 0

Share-Based Compensation - Pe93

Share-Based Compensation - Performance Shares Activity (Details) - Performance shares - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Weighted Number of Shares
Nonvested at beginning of period (in shares)	203,000
Granted (in shares)	147,000
Vested (in shares)	(89,040)
Forfeited (in shares)	(39,000)
Nonvested at end of period (in shares)	222,000	203,000
Weighted Average Grant Date Fair Value
Nonvested at January 1 (in dollars per share)	$ 42.82
Granted (in dollars per share)	30.63	$ 46.46	$ 38.89
Vested (in dollars per share)	38.89
Forfeited (in dollars per share)	24.12
Nonvested at December 31 (in dollars per share)	$ 37.20	$ 42.82

Supplemental Balance Sheet In94

Supplemental Balance Sheet Information - Inventories (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Inventory, Net [Abstract]
Finished goods	$ 210	$ 232
Work in progress	36	35
Raw materials	68	62
Total	$ 314	$ 329

Supplemental Balance Sheet In95

Supplemental Balance Sheet Information - Property, Plant and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Land and mineral deposits	$ 131	$ 135
Buildings and improvements	1,088	1,095
Machinery and equipment	2,505	2,563
Property, plant and equipment, gross	3,724	3,793
Reserves for depreciation and depletion	(1,936)	(1,885)
Total	1,788	1,908
Annual depreciation and depletion expense	$ 130	$ 134

Supplemental Balance Sheet In96

Supplemental Balance Sheet Information - Accrued Expenses (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Accrued Liabilities, Current [Abstract]
Self-insurance reserves	$ 20	$ 21
Employee compensation	40	42
Interest	45	45
Restructuring	0	1
Derivatives	17	18
Pension and other postretirement benefits	18	22
Environmental	16	16
Other	58	55
Total	$ 214	$ 220

Supplemental Balance Sheet In97

Supplemental Balance Sheet Information - Changes in Balances of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	$ (338)	$ 24	$ (233)
Other comprehensive income (loss) before reclassifications	2	(355)	234
Less: Amounts reclassified from AOCI, net of tax	(22)	7	(23)
Other comprehensive income (loss), net of tax	24	(362)	257
Balance at end of period	(314)	(338)	24
Derivatives
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	16	35	32
Other comprehensive income (loss) before reclassifications	(5)	(15)	4
Less: Amounts reclassified from AOCI, net of tax	(9)	4	1
Other comprehensive income (loss), net of tax	4	(19)	3
Balance at end of period	20	16	35
Pension and Other Postretirement Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	(302)	(32)	(303)
Other comprehensive income (loss) before reclassifications	74	(272)	247
Less: Amounts reclassified from AOCI, net of tax	(7)	(2)	(24)
Other comprehensive income (loss), net of tax	81	(270)	271
Balance at end of period	(221)	(302)	(32)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	(52)	21	38
Other comprehensive income (loss) before reclassifications	(67)	(68)	(17)
Less: Amounts reclassified from AOCI, net of tax	(6)	5	0
Other comprehensive income (loss), net of tax	(61)	(73)	(17)
Balance at end of period	$ (113)	$ (52)	$ 21

Supplemental Balance Sheet In98

Supplemental Balance Sheet Information - Amounts Reclassified from AOCI (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Cost of products sold	$ (3,085)	$ (3,070)	$ (2,989)
Net reclassification from ACOI for cash flow hedges included in income and gain from the sale of equity method investment to related party	13	2	2
Selling and administrative expenses	(317)	(339)	(320)
Less: Income tax expense on reclassification from AOCI included in income tax expense (benefit)	(729)	7	11
Net income	991	38	$ 46
Derivatives | Reclassification out of accumulated other comprehensive income
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Cost of products sold	(8)	4
Net reclassification from ACOI for cash flow hedges included in income and gain from the sale of equity method investment to related party	1	0
Less: Income tax expense on reclassification from AOCI included in income tax expense (benefit)	2	0
Net income	(9)	4
Pension and postretirement benefits | Reclassification out of accumulated other comprehensive income
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Cost of products sold	(5)	7
Selling and administrative expenses	(3)	(10)
Less: Income tax expense on reclassification from AOCI included in income tax expense (benefit)	(1)	(1)
Net income	(7)	(2)
Foreign Currency Translation | Reclassification out of accumulated other comprehensive income
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Selling and administrative expenses	(6)	5
Less: Income tax expense on reclassification from AOCI included in income tax expense (benefit)	0	0
Net income	$ (6)	$ 5

Supplemental Balance Sheet In99

Supplemental Balance Sheet Information - Textuals (Details) $ in Millions	12 Months Ended
	Dec. 31, 2015USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Net after-tax loss on derivatives reclassified from AOCI	$ 9

Supplemental Balance Sheet I100

Supplemental Balance Sheet Information - Asset Retirement Obligations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance as of beginning of period	$ 123	$ 132
Accretion expense	7	7
Liabilities incurred	1	2
Changes in estimated cash flows	(5)	(13)
Liabilities settled	(2)	(2)
Foreign currency translation	(5)	(3)
Balance as of end of period	$ 119	$ 123

Long-Lived Asset Impairment 101

Long-Lived Asset Impairment Charges - Impairment Charges (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges		$ 30	$ 0	$ 90	$ 0
Self-unloading ocean vessels
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges	$ 60			60
Machinery and equipment | Empire, Nevada and New Orleans, Louisiana
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges				16
Machinery and equipment | Gypsum, Ohio
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges				2
Future manufacturing facilities
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges				$ 12

Long-Lived Asset Impairment 102

Long-Lived Asset Impairment Charges - Textuals (Details) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2014USD ($)facility	Sep. 30, 2014USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)facility	Dec. 31, 2013USD ($)	Apr. 30, 2015ocean_vessel
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges		$ 30	$ 0	$ 90	$ 0
Self-unloading ocean vessels | ocean_vessel						2
Future facilities | facility	2			2
Self-unloading ocean vessels
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges	$ 60			$ 60
Machinery and equipment | Empire, Nevada and New Orleans, Louisiana
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges				16
Machinery and equipment | Gypsum, Ohio
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges				2
Future manufacturing facilities
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges				$ 12

Gypsum Transportation Limited (

Gypsum Transportation Limited (Details) $ in Millions	1 Months Ended	3 Months Ended								12 Months Ended
	Apr. 30, 2015USD ($)ocean_vessel	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Sep. 30, 2014USD ($)	Jun. 30, 2014USD ($)	Mar. 31, 2014USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Property, Plant and Equipment [Line Items]
Self-unloading ocean vessels | ocean_vessel	2
Long-lived asset impairment charges							$ 30			$ 0	$ 90	$ 0
Contract termination charge											6
Provision for bad debt										0	1	0
Proceeds from sale of assets										61	16	2
Gain on asset disposition										15	12	1
Early termination costs paid	$ 7
Cost to exit shipping operations				$ 6
Gain on disposal of shipping operations, net										1	0	0
Contract termination and (recovery) loss on receivable						$ 15				(6)	15	0
Operating profit (loss)		$ 98	$ 102	$ 105	$ 76	(24)	$ 22	$ 98	$ 66	381	162	258
Gypsum Transportation Limited
Property, Plant and Equipment [Line Items]
Operating profit (loss)										7	(52)	$ 20
GTL trading partner
Property, Plant and Equipment [Line Items]
Provision for bad debt											9
Receivable per release and debt settlement agreement		14								14
Loss on trade receivable		9								9
Remaining receivable that will be recorded when realization is assured		$ 5								$ 5
Self-unloading ocean vessels
Property, Plant and Equipment [Line Items]
Long-lived asset impairment charges						$ 60					$ 60
Proceeds from sale of assets	42
Gain on asset disposition	$ 7

Segments - Textuals (Details)

Segments - Textuals (Details) - segment	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting [Abstract]
Number of reportable segments	4
Net Sales | Home Depot, Inc.
Segment Reporting Information [Line Items]
Percentage of major customer net sales	16.00%	16.00%	15.00%

Segments - Gypsum, Ceilings and

Segments - Gypsum, Ceilings and Distribution (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net Sales:
Net sales	$ 925	$ 972	$ 970	$ 909	$ 954	$ 972	$ 948	$ 850	$ 3,776	$ 3,724	$ 3,570
Operating Profit (Loss):
Operating profit (loss)	98	$ 102	$ 105	$ 76	(24)	$ 22	$ 98	$ 66	381	162	258
Depreciation, Depletion and Amortization:
Depreciation, depletion and amortization									142	154	155
Capital Expenditures:
Capital expenditures									94	132	124
Assets	4,736				3,936				4,736	3,936
Operating Segments | Gypsum
Net Sales:
Net sales									2,397	2,403	2,262
Operating Profit (Loss):
Operating profit (loss)									348	169	261
Depreciation, Depletion and Amortization:
Depreciation, depletion and amortization									106	116	115
Capital Expenditures:
Capital expenditures									86	96	66
Assets	1,991				2,106				1,991	2,106
Operating Segments | Ceilings
Net Sales:
Net sales									499	513	568
Operating Profit (Loss):
Operating profit (loss)									89	87	98
Depreciation, Depletion and Amortization:
Depreciation, depletion and amortization									16	14	14
Capital Expenditures:
Capital expenditures									3	30	54
Assets	276				285				276	285
Operating Segments | Distribution
Net Sales:
Net sales									1,428	1,345	1,245
Operating Profit (Loss):
Operating profit (loss)									27	16	6
Depreciation, Depletion and Amortization:
Depreciation, depletion and amortization									11	12	12
Capital Expenditures:
Capital expenditures									5	5	3
Assets	376				412				376	412
Corporate
Operating Profit (Loss):
Operating profit (loss)									(95)	(109)	(93)
Depreciation, Depletion and Amortization:
Depreciation, depletion and amortization									9	12	14
Capital Expenditures:
Capital expenditures									0	1	1
Assets	1,487				489				1,487	489
Eliminations
Net Sales:
Net sales									(548)	(537)	(505)
Operating Profit (Loss):
Operating profit (loss)									12	(1)	$ (14)
Capital Expenditures:
Assets	(76)				(91)				(76)	(91)
Equity method investments
Capital Expenditures:
Assets	$ 682				$ 735				$ 682	$ 735

Segments - Geographic Informati

Segments - Geographic Information (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Geographic Areas, Revenues from External Customers [Abstract]
Net sales	$ 925	$ 972	$ 970	$ 909	$ 954	$ 972	$ 948	$ 850	$ 3,776	$ 3,724	$ 3,570
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	1,788				1,908				1,788	1,908
Reportable geographical components | United States
Geographic Areas, Revenues from External Customers [Abstract]
Net sales									3,387	3,220	3,029
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	1,622				1,665				1,622	1,665
Reportable geographical components | Canada
Geographic Areas, Revenues from External Customers [Abstract]
Net sales									379	406	417
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	90				112				90	112
Reportable geographical components | Other Foreign
Geographic Areas, Revenues from External Customers [Abstract]
Net sales									196	283	309
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	$ 76				$ 131				76	131
Geographic transfers
Geographic Areas, Revenues from External Customers [Abstract]
Net sales									$ (186)	$ (185)	$ (185)

Segments - UBBP (Details)

Segments - UBBP (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Assets	$ 4,736	$ 3,936
USG Boral Building Products
Segment Reporting Information [Line Items]
Net sales	1,003	927
Operating profit	124	95
Net income attributable to UBBP	96	67
Depreciation, depletion, and amortization	43	31
Capital expenditures	49	40
Assets	1,303	1,435
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	680	731
USG Boral Building Products | Reportable geographical components | Australia
Segment Reporting Information [Line Items]
Net sales	345	312
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	216	245
USG Boral Building Products | Reportable geographical components | South Korea
Segment Reporting Information [Line Items]
Net sales	200	197
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	106	113
USG Boral Building Products | Reportable geographical components | China
Segment Reporting Information [Line Items]
Net sales	120	122
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	116	127
USG Boral Building Products | Reportable geographical components | Oman
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	103	96
USG Boral Building Products | Reportable geographical components | Thailand
Segment Reporting Information [Line Items]
Net sales	145	133
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	72	72
USG Boral Building Products | Reportable geographical components | Other
Segment Reporting Information [Line Items]
Net sales	234	206
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	67	78
USG Boral Building Products | Geographic transfers
Segment Reporting Information [Line Items]
Net sales	$ (41)	$ (43)

Income Taxes - Income from Cont

Income Taxes - Income from Continuing Operations (Details) - USD ($) $ in Millions	12 Months Ended			15 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015
Income (loss) before income taxes
U.S.	$ 178	$ 27	$ 17	$ 194
Foreign	84	19	42
Income from continuing operations before income taxes	$ 262	$ 46	$ 59

Income Taxes - Income Tax Expen

Income Taxes - Income Tax Expense (Benefit) on Continuing Operations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current:
Federal	$ 0	$ 0	$ 0
Foreign	12	2	10
State	1	1	1
Income tax expense (benefit) on continuing operations	13	3	11
Deferred:
Federal	(621)	0	(2)
Foreign	(4)	4	2
State	(117)	0	0
Deferred income tax expense (benefit) on continuing operations	(742)	4	0
Provision for income tax expense	$ (729)	$ 7	$ 11

Income Taxes - Textuals (Detail

Income Taxes - Textuals (Details) - USD ($)	12 Months Ended			15 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Federal statutory rate	35.00%	35.00%	35.00%
Pre-tax earnings	$ 178,000,000	$ 27,000,000	$ 17,000,000	$ 194,000,000
Decrease in valuation allowance against deferred tax assets	948,000,000
Amount related to evaluation for need for valuation allowance against deferred tax assets	731,000,000
Decrease in underlying deferred tax assets	217,000,000
Income Tax Examination [Line Items]
Net deferred tax assets	723,000,000	1,000,000		723,000,000
Valuation allowance	75,000,000	1,023,000,000		75,000,000
Approximate federal net operating loss carryforwards	1,755,000,000			1,755,000,000
Approximate federal alternative minimum tax credit carryforwards	40,000,000			40,000,000
Minimum taxable income needed to fully realize the U.S. federal net deferred tax assets	1,870,000,000			1,870,000,000
State deferred tax assets	230,000,000			230,000,000
Approximate gross deferred tax assets operating loss and tax credit carry forwards that will expire in current year	27,000,000			27,000,000
Foreign deferred tax assets	$ 1,000,000			1,000,000
Percentage of change in ownership (more than)	50.00%
Period of change in ownership	3 years
Annual U.S. federal NOL utilization	$ 92,000,000			92,000,000
Total amounts of tax penalties and interest expense recognized on consolidated balance sheet	1,000,000	3,000,000		1,000,000
Total amounts of interest and penalties recognized in consolidated statements of operations	0	0	0
Total amount of unrecognized tax benefit that would affect our effective tax rate	$ 17,000,000	$ 5,000,000	$ 7,000,000	17,000,000
Income tax examinations, possible period for resolution	12 months
Undistributed earnings	$ 682,000,000			682,000,000
Minimum
Income Tax Examination [Line Items]
Period of statutes of limitations	3 years
Maximum
Income Tax Examination [Line Items]
Period of statutes of limitations	5 years
State and local jurisdiction
Income Tax Examination [Line Items]
Valuation allowance	$ 74,000,000			74,000,000
Foreign tax authority
Income Tax Examination [Line Items]
Valuation allowance	$ 1,000,000			$ 1,000,000

Income Taxes - Differences Betw

Income Taxes - Differences Between Provisions for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Differences between actual provisions for income taxes and provisions for income taxes at the U.S. federal statutory rate (35%)
Taxes on income from continuing operations at U.S. federal statutory rate	$ 92	$ 16	$ 21
Foreign earnings subject to different tax rates	(3)	16	(6)
State income tax, net of federal benefit	9	1	1
Change in valuation allowance	(827)	(9)	(8)
Income from equity method investments	(16)	(12)	0
Withholding taxes	0	2	6
Other, net	2	(1)	(3)
Tax release from AOCI	0	(2)	0
Gain on deconsolidation	0	(7)	0
Benefits from unrecognized tax positions	(6)	0	0
Tax benefit not realized on pension loss	0	3	0
Tax on distribution of foreign earnings	20	0	0
Provision for income tax expense	$ (729)	$ 7	$ 11
Effective income tax rate	(277.70%)	15.30%	18.60%

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Deferred Tax Assets:
Net operating loss and tax credit carryforwards	$ 779	$ 944
Pension and postretirement benefits	150	196
Goodwill and other intangible assets	24	29
Reserves not deductible until paid	29	47
Self insurance	11	15
Capitalized interest	13	15
Inventories	8	8
Share-based compensation	33	37
Other	5	11
Deferred tax assets before valuation allowance	1,052	1,302
Valuation allowance	(75)	(1,023)
Total deferred tax assets	977	279
Deferred Tax Liabilities:
Property, plant and equipment	254	278
Other	0	0
Total deferred tax liabilities	254	278
Net deferred tax assets	$ 723	$ 1

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation of the beginning and ending amount of unrecognized tax benefits
Balance as of beginning of period	$ 22	$ 22	$ 16
Tax positions related to the current period:
Gross increase	4	2	4
Gross decrease	0	0	0
Tax positions related to prior periods:
Gross increase	0	0	2
Gross decrease	(1)	0	0
Settlements	(6)	(2)	0
Lapse of statutes of limitations	(1)	0	0
Balance as of end of period	$ 18	$ 22	$ 22

Earnings Per Share - Reconcilia

Earnings Per Share - Reconciliation of Basic Income Per Share to Diluted Income Per Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Income from continuing operations	$ 812	$ 76	$ 79	$ 24	$ (53)	$ (11)	$ 58	$ 45	$ 991	$ 39	$ 48
Net income (loss) attributable to noncontrolling interest									0	1	(1)
Income from continuing operations attributable to USG									991	38	49
Loss from discontinued operations	0	0	0	0	0	0	(1)	0	0	(1)	(2)
Net income attributable to USG	$ 812	$ 76	$ 79	$ 24	$ (53)	$ (12)	$ 57	$ 45	991	37	47
Effect of dilutive securities - Deferred compensation program for non-employee directors									(1)	0	0
Income available to shareholders									$ 990	$ 37	$ 47
Average common shares (in shares)									145,457,208	141,722,616	108,891,703
Dilutive RSUs, MSUs, performance shares and stock options (in shares)									1,600,000	2,400,000	2,500,000
Deferred shares associated with a deferred compensation program for non-employee directors (in shares)									100,000	200,000	0
Average diluted common shares (in shares)									147,246,600	144,296,316	111,434,543
Basic earnings (loss) per average common share:
Income from continuing operations (in dollars per share)	$ 5.58	$ 0.52	$ 0.54	$ 0.16	$ (0.36)	$ (0.09)	$ 0.40	$ 0.33	$ 6.81	$ 0.27	$ 0.45
Loss from discontinued operations (in dollars per share)									0	(0.01)	(0.02)
Net income (in dollars per share)									6.81	0.26	0.43
Diluted earnings (loss) per average common share:
Income from continuing operations (in dollars per share)	$ 5.51	$ 0.52	$ 0.54	$ 0.16	$ (0.36)	$ (0.09)	$ 0.39	$ 0.32	6.73	0.26	0.44
Loss from discontinued operations (in dollars per share)									0	(0.01)	(0.02)
Net income (in dollars per share)									$ 6.73	$ 0.25	$ 0.42

Earnings Per Share - Textuals (

Earnings Per Share - Textuals (Details) - 10% convertible senior notes due 2018 - USD ($) $ in Millions	1 Months Ended
	Apr. 30, 2014	Dec. 31, 2013	Dec. 31, 2015
Earnings (Loss) Per Share [Line Items]
Stated interest rate			10.00%
Converted debt aggregate principal amount	$ 75	$ 325

Earnings Per Share - Anti-Dilut

Earnings Per Share - Anti-Dilutive Securities (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stock options, RSUs, MSUs and performance shares
Earnings (Loss) Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted earnings (loss) per share (in shares)	1.9	2.1	2.2
Convertible debt securities | 10% convertible senior notes due 2018
Earnings (Loss) Per Share [Line Items]
Shares issuable upon conversion of convertible senior notes not included in computation of diluted earnings (loss) per share (in shares)	0	0	6.6
Deferred shares associated with a deferred compensation program for non-employee directors
Earnings (Loss) Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted earnings (loss) per share (in shares)	0	0	0.2

Stockholder Rights Plan (Detail

Stockholder Rights Plan (Details)	Mar. 22, 2013	Dec. 31, 2015	May. 09, 2013
Equity [Abstract]
Ownership interest to cause cumulative change in ownership (or more than) (as a percent)	5.00%
Period of cumulative change in ownership	3 years
Beneficial owner of common stock percentage (or more than)	4.90%		4.90%
Period of review		3 years
Beneficial ownership percentage post standstill period (up to)		50.00%
Beneficial owner of common stock percentage in future (more than)		50.00%
Period of offer to purchase common stock		60 days

Lease Commitments - Textuals (D

Lease Commitments - Textuals (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Lease Commitments [Abstract]
Lease expense	$ 75	$ 75	$ 73

Lease Commitments - Future Mini

Lease Commitments - Future Minimum Lease Payments (Details) $ in Millions	Dec. 31, 2015USD ($)
Future minimum lease payments
2,016	$ 72
2,017	65
2,018	53
2,019	40
2,020	26
After 2,020	$ 32

Litigation (Details)

Litigation (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2014USD ($)	Dec. 31, 2015USD ($)person	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	Mar. 31, 2015USD ($)DefendantsHomebuilder
Commitments and Contingencies Disclosure [Abstract]
Litigation settlement charge	$ 48,000	$ 0	$ 48,000	$ 0
Direct purchaser settlement charge	39,250
Indirect purchaser settlement charge	$ 8,750
Number of people that appealed final judgement | person		1
Number of defendants named in lawsuit | Defendants					7
Number of homebuilders asserting individual claims | Homebuilder					12
Original litigation settlement					$ 48,000
Accrual potential liability for environmental cleanup		$ 16,000	$ 16,000

Quarterly Financial Data (un121

Quarterly Financial Data (unaudited) - Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 925	$ 972	$ 970	$ 909	$ 954	$ 972	$ 948	$ 850	$ 3,776	$ 3,724	$ 3,570
Gross profit	172	183	183	153	160	176	175	143	691	654	581
Operating profit (loss)	98	102	105	76	(24)	22	98	66	381	162	258
Income (loss) from continuing operations	812	76	79	24	(53)	(11)	58	45	991	39	48
Loss from discontinued operations, net of tax	0	0	0	0	0	0	(1)	0	0	(1)	(2)
Net income (loss) attributable to USG	$ 812	$ 76	$ 79	$ 24	$ (53)	$ (12)	$ 57	$ 45	$ 991	$ 37	$ 47
Income from continuing operations per common share:
Basic (in dollars per share)	$ 5.58	$ 0.52	$ 0.54	$ 0.16	$ (0.36)	$ (0.09)	$ 0.40	$ 0.33	$ 6.81	$ 0.27	$ 0.45
Diluted (in dollars per share)	$ 5.51	$ 0.52	$ 0.54	$ 0.16	$ (0.36)	$ (0.09)	$ 0.39	$ 0.32	$ 6.73	$ 0.26	$ 0.44

Quarterly Financial Data (un122

Quarterly Financial Data (unaudited) - Textuals (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Reversal of income tax valuation allowance			$ 731
Litigation settlement charge		$ 48	0	$ 48	$ 0
Property, Plant and Equipment [Line Items]
Long-lived asset impairment charges		$ 30	0	90	0
Contract termination charge and (recovery) loss on receivable	$ 15		(6)	15	0
Pension settlement charges	13		$ 1	13	$ 16
Self-unloading ocean vessels
Property, Plant and Equipment [Line Items]
Long-lived asset impairment charges	$ 60			$ 60

Schedule II - Valuation And 123

Schedule II - Valuation And Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Doubtful accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 20	$ 10	$ 14
Charged to costs and expenses	(6)	9	0
Charged to other accounts	0	1	1
Deductions	(3)	0	(5)
Balance at end of period	11	20	10
Cash discounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	2	2	2
Charged to costs and expenses	49	45	42
Charged to other accounts	0	0	0
Deductions	(48)	(45)	(42)
Balance at end of period	3	2	2
Income tax valuation allowance
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	1,023	995	1,125
Charged to costs and expenses	0	1	(2)
Charged to other accounts	0	112	0
Deductions	(948)	(85)	(128)
Balance at end of period	$ 75	$ 1,023	$ 995