Usg (USG) 10-Q 25 Jul 18 2018 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information	6 Months Ended
	Jun. 30, 2018shares
Document and Entity Information [Abstract]
Entity Registrant Name	USG CORP
Entity Central Index Key	757,011
Document Type	10-Q
Document Period End Date	Jun. 30, 2018
Amendment Flag	false
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding	139,493,175

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Net sales	$ 880	$ 811	$ 1,666	$ 1,578
Cost of products sold	696	643	1,343	1,251
Gross profit	184	168	323	327
Selling and administrative expenses	109	73	202	148
Operating profit	75	95	121	179
Income from equity method investments	12	14	21	27
Interest expense	(15)	(19)	(29)	(39)
Interest income	2	0	3	1
Loss on extinguishment of debt	0	(22)	0	(22)
Other (expense) income, net	(3)	(2)	0	4
Income from continuing operations before income taxes	71	66	116	150
Income tax expense	(13)	(20)	(22)	(49)
Income from continuing operations	58	46	94	101
Income (loss) from discontinued operations, net of tax	0	(10)	1	(10)
Net income	$ 58	$ 36	$ 95	$ 91
Earnings per average common share - basic:
Income from continuing operations (in dollars per share)	$ 0.41	$ 0.32	$ 0.66	$ 0.69
Income (loss) from discontinued operations (in dollars per share)	0	(0.07)	0.01	(0.07)
Net income (in dollars per share)	0.41	0.25	0.67	0.62
Earnings per average common share - diluted:
Income from continuing operations (in dollars per share)	0.41	0.31	0.65	0.68
Income (loss) from discontinued operations (in dollars per share)	0	(0.07)	0.01	(0.07)
Net income (in dollars per share)	$ 0.41	$ 0.24	$ 0.66	$ 0.61
Average common shares (in shares)	139,617,875	144,526,900	140,540,426	145,753,098
Dilutive awards under long-term incentive plan (in shares)	1,262,046	2,113,193	2,222,766	2,317,971
Deferred shares for non-employee directors (in shares)	0	220,846	0	220,404
Average diluted common shares (in shares)	140,879,921	146,860,939	142,763,192	148,291,473

Condensed Consolidated Stateme3

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 58	$ 36	$ 95	$ 91
Derivatives qualifying as cash flow hedges:
Gain (loss) on derivatives qualifying as cash flow hedges, net of tax (benefit) of $0, ($2), $0 and ($5), respectively	2	(2)	2	(8)
Less: Reclassification adjustment for loss on derivatives included in net income, net of tax of $0 in all periods	(2)	(1)	(2)	(1)
Net derivatives qualifying as cash flow hedges	4	(1)	4	(7)
Pension and postretirement benefits:
Changes in pension and postretirement benefits, net of tax of $0, $2, $0 and $2, respectively	1	4	3	3
Less: Amortization of prior service cost included in net periodic pension cost, net of tax (benefit) of $0, ($7), ($1) and ($7), respectively	(2)	(12)	(3)	(12)
Net pension and postretirement benefits	3	16	6	15
Foreign currency translation:
Changes in foreign currency translation, net of tax of $0 in all periods	(38)	8	(26)	48
Less: Translation loss realized upon sale of foreign equity method investment, net of tax (benefit) of ($2), $0, ($2) and $0, respectively	(4)	0	(4)	0
Net foreign currency translation	(34)	8	(22)	48
Other comprehensive income, net of tax	(27)	23	(12)	56
Comprehensive income	$ 31	$ 59	$ 83	$ 147

Condensed Consolidated Stateme4

Condensed Consolidated Statements of Comprehensive Income (Parentheticals) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Derivatives Qualifying as Hedges, Tax:
Loss on derivatives qualifying as cash flow hedges, tax (benefit)	$ 0	$ (2)	$ 0	$ (5)
Less: Reclassification adjustment for loss on derivatives included in net income, tax expense (benefit)	0	0	0	0
Pension and Other Postretirement Benefit Plans, Tax:
Changes in pension and postretirement benefits, tax (benefit)	0	2	0	2
Net reclassification in AOCI for amortization of prior service cost included other net periodic postretirement benefit	0	(7)	(1)	(7)
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax [Abstract]
Translation loss realized upon sale of foreign equity method investment, tax	(2)	0	(2)	0
Changes in foreign currency translation, tax	$ 0	$ 0	$ 0	$ 0

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Assets
Cash and cash equivalents	$ 246	$ 394
Short-term marketable securities	58	62
Receivables (net of reserves 2018 - $10 and 2017 - $9)	342	233
Inventories	265	252
Income taxes receivable	16	15
Other current assets	36	35
Total current assets	963	991
Long-term marketable securities	38	37
Property, plant and equipment (net of accumulated depreciation and depletion - 2018 - $2,111 and 2017 - $2,053)	1,793	1,762
Deferred income taxes	264	287
Equity method investments	666	686
Goodwill and intangible assets	42	43
Other assets	47	45
Total assets	3,813	3,851
Liabilities and Stockholders’ Equity
Accounts payable	281	280
Accrued expenses	130	135
Income taxes payable	1	0
Total current liabilities	412	415
Long-term debt	1,078	1,078
Deferred income taxes	4	4
Pension and other postretirement benefits	277	326
Other liabilities	179	183
Total liabilities	1,950	2,006
Stockholders' Equity:
Preferred stock	0	0
Common stock	15	15
Treasury stock at cost	(219)	(169)
Additional paid-in capital	3,040	3,057
Accumulated other comprehensive loss	(401)	(389)
Retained earnings (accumulated deficit)	(572)	(669)
Total stockholders’ equity	1,863	1,845
Total liabilities and stockholders’ equity	$ 3,813	$ 3,851

Condensed Consolidated Balance6

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Reserves on receivables	$ 10	$ 9
Accumulated depreciation	$ 2,111	$ 2,053

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Operating Activities
Net income	$ 95	$ 91
Income (loss) from discontinued operations, net of tax	1	(10)
Income from continuing operations	94	101
Adjustments to reconcile net income from continuing operations to net cash:
Depreciation, depletion and amortization	76	65
Loss on extinguishment of debt	0	22
Share-based compensation expense	10	9
Deferred income taxes	20	48
Gain on asset dispositions	(13)	(1)
Loss on sale of equity method investment	8	0
Income from equity method investments	(21)	(27)
Dividends received from equity method investments	16	23
Pension settlement	0	7
Change in operating assets and liabilities	(176)	(117)
Other, net	4	(1)
Net cash provided by operating activities of continuing operations	18	129
Net cash provided by (used for) operating activities of discontinued operations	1	(1)
Net cash provided by operating activities	19	128
Investing Activities
Purchases of marketable securities	(49)	(54)
Sales or maturities of marketable securities	51	53
Capital expenditures	(109)	(72)
Net proceeds from asset dispositions	14	2
Net proceeds from sale of equity method investment	3	0
Working capital adjustment from acquisition of business	2	0
Insurance proceeds	0	1
Net cash used for investing activities of continuing operations	(88)	(70)
Net cash provided by investing activities of discontinued operations	0	6
Net cash used for investing activities	(88)	(64)
Financing Activities
Issuance of debt	0	500
Repayment of debt	0	(520)
Payment of debt issuance fees	0	(8)
Issuance of common stock	6	3
Repurchase of common stock	(76)	(97)
Repurchases of common stock to satisfy employee tax withholding obligations	(7)	(4)
Net cash used for financing activities of continuing operations	(77)	(126)
Effect of exchange rate changes on cash from continuing operations	(2)	6
Net decrease in cash and cash equivalents from continuing operations	(149)	(61)
Net increase in cash and cash equivalents from discontinued operations	1	5
Net decrease in cash and cash equivalents	(148)	(56)
Cash and cash equivalents at beginning of period	394	427
Cash and cash equivalents at end of period	246	371
Supplemental Cash Flow Disclosures:
Interest paid, net of capitalized interest	27	48
Income taxes paid, net of refunds received	4	9
Noncash Investing and Financing Activities:
Amount in accounts payable for capital expenditures	$ 13	$ 7

Organization, Consolidation and

Organization, Consolidation and Presentation of Financial Statements	6 Months Ended
	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization, Consolidation and Presentation of Financial Statements	Organization, Consolidation and Presentation of Financial Statements PREPARATION OF FINANCIAL STATEMENTS We prepared the accompanying unaudited condensed consolidated financial statements of USG Corporation in accordance with applicable United States Securities and Exchange Commission, or SEC, guidelines pertaining to interim financial information. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses. Actual results could differ materially from those estimates. In the opinion of our management, the financial statements reflect all adjustments, which are of a normal recurring nature, necessary for a fair presentation of our financial results for the interim periods. The results of operations for the three and six months ended June 30, 2018 are not necessarily indicative of the results of operations to be expected for the entire year. SEGMENTS Our reportable segments are determined considering both qualitative and quantitative metrics for aggregation of the product type within geographies for which discrete financial information is available. We have five reportable segments: U.S. Wallboard and Surfaces, U.S. Performance Materials, U.S. Ceilings, Canada, and USG Boral Building Products, or UBBP. Our U.S. Wallboard and Surfaces, U.S. Performance Materials and U.S. Ceilings reportable segments are identified based on products manufactured and marketed. Our Canada segment is a separately reportable segment, as while it has similar qualitative factors to U.S. operations, it has different quantitative metrics and, therefore, cannot be aggregated. Our operating segments in Mexico and Latin America are included in Other as reconciling items to our consolidated segments. This segment structure was effective for the quarter ended December 31, 2017. Our prior period results have been recast to reflect these changes and present comparative year over year information by segment. See Note 4 , Segments. These condensed consolidated financial statements and notes are to be read in conjunction with the financial statements and notes included in USG’s Annual Report on Form 10-K for the fiscal year ended December 31, 2017 , which we filed with the SEC on February 14, 2018 . RECENTLY ADOPTED ACCOUNTING PRONOUNCEMENTS We adopted Accounting Standard Update, or ASU, 2018-02, "Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income," in the first quarter of 2018. The ASU allows for the reclassification of stranded tax effects on items resulting from the Tax Cuts and Jobs Act, or the 2017 Tax Act, from accumulated other comprehensive income, or AOCI, to retained earnings. Tax effects unrelated to the 2017 Tax Act are released from AOCI using either the specific identification approach or the portfolio approach based on the nature of the underlying item. We elected not to reclassify the income tax effects of the 2017 Tax Act. We adopted ASU 2017-07, “Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost,” on January 1, 2018 using the practical expedient. This ASU required us to disaggregate and present current service cost along with other current compensation costs for employees while presenting other net benefit cost components below operating profit. In addition, only the service cost component of net benefit cost is eligible for capitalization in our inventory and fixed assets. We retrospectively adopted the presentation of service cost and prospectively adopted the capitalization of only service cost into inventory and fixed assets. The effect of the adoption of ASU 2017-07 on our condensed consolidated statements of income for the three and six months ended June 30, 2017 was as follows. (millions) Three months ended June 30, 2017 Six months ended June 30, 2017 As Restated Adjustment for Adoption of ASU 2017-07 As Previously Reported As Restated Adjustment for Adoption of ASU 2017-07 As Previously Reported Gross profit $ 168 $ — $ 168 $ 327 $ (5 ) $ 332 Operating profit 95 (1 ) 96 179 (8 ) 187 Other income, net (2 ) 1 (3 ) 4 8 (4 ) Net income 36 — 36 91 — 91 We adopted ASU 2014-09, “Revenue from Contracts with Customers (Topic 606),” and all related amendments on January 1, 2018 using the modified retrospective method using practical expedients. Topic 606 supersedes the revenue recognition requirements in "Revenue Recognition (Topic 605)" and requires entities to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. Upon adoption, we recorded an increase of $2 million to our opening balance of retained earnings for the cumulative effect of adopting Topic 606. The adjustment related to a change to the point in time at which we record revenue for most customers. Prior period amounts have not been restated and continue to be reported under the legacy accounting guidance of Topic 605. As of and for the three and six months ended June 30, 2018, the impact of applying Topic 606 as compared to applying Topic 605 is immaterial to our financial statements. In addition to our cumulative effect adjustment, our adoption of Topic 606 resulted in additional quantitative disclosure of revenue by product and in the modification of certain significant accounting policies. See Note 4 , Segments, for our revenue disaggregated by product and the revised polices below. Revenue Recognition We recognize revenue upon transfer of control of our products to the customer which generally occurs upon shipment. We enter into agreements with customers to offer rebates, generally based on achievement of specified sales levels and various marketing allowances that are common industry practice. Reductions to revenue for customer programs and incentive offerings, including promotions and other volume-based incentives, are estimated using the most likely amount method and recorded in the period in which the sale occurs. Provisions for early payment discounts are accrued in the same period in which the sale occurs. We do not have any material payment terms as payment is received shortly after the point of sale. We pay commissions to third parties to obtain contracts. As these contracts are less than one year, these costs are expensed as incurred. Shipping and Handling Costs We include shipping and handling costs billed to customers in net sales. We account for related costs as fulfillment activities and present the costs in cost of products sold when control of our products transfers to the customer. RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842),” which supersedes existing lease guidance to require lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by long-term leases and to disclose additional quantitative and qualitative information about leasing arrangements. Subsequently, the FASB has issued various ASUs to provide further clarification around certain aspects of Topic 842. We will adopt the new standard on January 1, 2019 using the modified retrospective approach. As a result of the new standard, we will implement a new lease accounting system, new processes and accounting policies. Further, we anticipate the adoption of ASU 2016-02 will have a significant impact to our condensed consolidated balance sheets and disclosures. We are currently finalizing our accounting policies, implementing a new leasing system, determining changes needed in current processes for lease accounting and verifying the completeness of our lease population and, thus, we are unable to quantify the financial statement impact at this time.

Acquisitions and Dispositions

Acquisitions and Dispositions	6 Months Ended
	Jun. 30, 2018
Business Combinations And Discontinued Operations and Disposal Groups [Abstract]
Acquisitions and Dispositions	Acquisitions and Dispositions Acquisition of Ceilings Plus On November 30, 2017, we completed our acquisition of Ceilings Plus for $50 million , net of working capital adjustments. The addition of Ceilings Plus to our U.S. Ceilings segment expands our operations in the specialty ceilings markets. We finalized our valuation in the second quarter of 2018. The fair value of tangible assets acquired, less liabilities assumed, in connection with the Ceilings Plus acquisition was $15 million . The fair value of intangible assets acquired, which included customer relationships and trade names, totaled $20 million . The resulting goodwill recorded was $15 million and all is expected to be deductible for tax purposes. The goodwill resulting from this acquisition consists largely of Ceilings Plus' expected future product sales and synergies with the existing U.S. Ceilings product offerings. Discontinued Operations On October 31, 2016, we completed the sale of our L&W Supply, or L&W, distribution business to ABC Supply. For the three and six months ended June 30, 2017, we recorded a loss of $9 million , net of tax, for L&W to "Income (loss) from discontinued operations", which primarily reflected a pension settlement charge related to lump sum benefits paid to former employees of L&W. Upon the close of the sale, we entered into a supply agreement with L&W, and for the three and six months ended June 30, 2018 , we recorded sales of $122 million and $217 million , respectively, and cash inflows related to payments on trade receivables during those same periods of $107 million and $211 million , respectively. For the comparative periods in 2017, we recorded sales of $134 million and $265 million , respectively, and cash inflows related to payments on trade receivables of $143 million and $252 million , respectively. Merger Agreement On June 10, 2018, we entered into an Agreement and Plan of Merger, as it may be amended from time to time, or the Merger Agreement, with Knauf and World Cup Acquisition Corporation, a Delaware corporation and an indirect, wholly-owned subsidiary of Knauf, or Merger Sub. The Merger Agreement provides that, subject to the satisfaction of customary closing conditions, Merger Sub will be merged with and into USG, or the Merger, with USG continuing as the surviving corporation and an indirect, wholly-owned subsidiary of Knauf. Pursuant to the terms of the Merger Agreement, at the effective time of the Merger, each share of common stock, par value $0.10 , of USG issued and outstanding immediately prior to the effective time of the Merger (other than shares of common stock owned by Knauf and its subsidiaries, the Company and its subsidiaries and certain excluded holders) will be converted into the right to receive $43.50 in cash, without interest and subject to tax withholding. In addition, as contemplated by the Merger Agreement, USG is expected to declare a conditional special cash dividend of $0.50 per share, or the conditional special dividend, payable to holders of our common stock on the record date for the special meeting of stockholders held for the purpose, among other things, of adopting the Merger Agreement and the Merger, and will be paid following the certification of those results if the Merger Agreement is adopted by our stockholders. The Merger, which is currently expected to close in early 2019, is subject to the satisfaction or waiver of certain customary closing conditions, including, among others, adoption of the Merger Agreement by the affirmative vote of holders of at least 80% of outstanding shares of our common stock and receipt of certain regulatory approvals. The Merger Agreement contains certain termination rights for both USG and Knauf. If the Merger Agreement is terminated under certain specified circumstances, we will be required to pay Knauf a termination fee of $215 million (including under specified circumstances in connection with our entry into an agreement with respect to a superior proposal, as defined in the Merger Agreement). We have incurred $8 million and $9 million , pre-tax, of merger related costs for the three and six months ended June 30, 2018 , respectively, which are included in Selling and Administrative Expenses on our condensed consolidated statement of income.

Equity Method Investments

Equity Method Investments	6 Months Ended
	Jun. 30, 2018
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	Equity Method Investments Equity method investments as of June 30, 2018 and December 31, 2017 , were as follows: June 30, 2018 December 31, 2017 (dollars in millions) Carrying Value Ownership Percentage Carrying Value Ownership Percentage USG Boral Building Products $ 664 50% $ 679 50% Other equity method investments 2 50% 7 33% - 50% Total equity method investments $ 666 $ 686 INVESTMENT IN USG BORAL BUILDING PRODUCTS UBBP is our 50 / 50 joint ventures with Boral Limited, or Boral. We account for our investment in UBBP using the equity method of accounting. During the second quarter of 2018, UBBP paid cash dividends on its earnings through March 2018 of which our 50% share totaled $16 million . As of June 30, 2018 , the amount of our consolidated retained earnings which represents undistributed earnings from UBBP is $66 million . In the event certain U.S. Dollar denominated performance targets are satisfied by UBBP, we will be obligated to pay Boral an earnout payment of up to $50 million based on performance through 2019. We have not recorded a liability for this 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 changes, we will record a liability representing the present value of the earnout payment with a corresponding increase to our investment. UBBP is operated in accordance with the terms of a Shareholders Agreement. If we are subject to a change of control as defined by the Shareholders Agreement, including the proposed acquisition of USG by Gebr. Knauf KG, a limited partnership ( Kommanditgesellschaft ) organized under the laws of Germany, or Knauf, we may be required to sell our entire interest in UBBP at fair market value, as determined in accordance with the Shareholders Agreement. Our underlying net assets in our investments are denominated in a foreign currency, and translation gains or losses will impact the recorded value of our investments. Translation gains or losses recorded in other comprehensive income were as follows: Three months ended June 30, Six months ended June 30, (millions) 2018 2017 2018 2017 Translation (loss) gain $ (24 ) $ (1 ) $ (21 ) $ 23 Summarized financial information for UBBP is as follows: Three months ended June 30, Six months ended June 30, (millions) 2018 2017 2018 2017 USG Boral Building Products Net sales $ 297 $ 287 $ 584 $ 563 Gross profit 83 91 162 177 Operating profit 31 40 59 75 Income from continuing operations before income taxes 35 44 67 82 Net income 25 28 45 54 Net income attributable to USG Boral Building Products 24 28 43 53 USG share of income from investment accounted for using the equity method 12 14 21 27 TRANSACTIONS WITH UBBP Our U.S. Wallboard and Surfaces and U.S. Performance Materials segments sell products to UBBP. Total sales to UBBP for the three and six months ended June 30, 2018 and 2017 were immaterial. In 2014, in connection with the formation of UBBP, we contributed our ownership interest in a joint venture in China to UBBP, but retained our loan receivable from this joint venture. As of June 30, 2018 and December 31, 2017 , the loan receivable, including interest, totaled $13 million and is included in "Other assets" on our accompanying condensed consolidated balance sheets. INVESTMENT IN SOUTH AFRICA JOINT VENTURE During the second quarter of 2018, we completed the sale of our 33% interest in a joint venture in South Africa for approximately $3 million . We recorded a loss of $8 million , or $5 million net of tax, on the sale in " Other (expense) income, net " on our accompanying condensed consolidated income statements. The loss was driven primarily by foreign currency losses included in equity that were recognized upon the disposition of the joint venture and was recorded within Other as it does not relate to a reportable segment.

Segments

Segments	6 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
Segments	Segments During the fourth quarter of 2017, as part of the realignment of our operating structure, we changed the composition of our reportable segments, effective for the quarter ended December 31, 2017. See Note 1, Organization, Consolidation and Presentation of Financial Statements, for additional information regarding our five reportable segments. See Note 3 , Equity Method Investments, for segment results for UBBP. Segment results for our U.S. Wallboard and Surfaces, U.S. Performance Materials, U.S. Ceilings and Canada segments were as follows: Three months ended June 30, Six months ended June 30, (millions) 2018 2017 2018 2017 Net Sales : U.S. Wallboard and Surfaces $ 512 $ 482 $ 953 $ 951 U.S. Performance Materials 105 100 197 186 U.S. Ceilings 139 118 277 230 Canada 121 104 232 200 Other 65 59 125 115 Eliminations (62 ) (52 ) (118 ) (104 ) Total $ 880 $ 811 $ 1,666 $ 1,578 Operating Profit (Loss) : U.S. Wallboard and Surfaces $ 81 $ 78 $ 130 $ 157 U.S. Performance Materials (6 ) 8 (5 ) 14 U.S. Ceilings 23 23 42 43 Canada 8 2 10 4 Other 4 1 8 2 Corporate (35 ) (17 ) (64 ) (41 ) Total $ 75 $ 95 $ 121 $ 179 Net sales disaggregated by product type were as follows: Three months ended June 30, 2018 (millions) U.S. Wallboard and Surfaces U.S. Performance Materials U.S. Ceilings Canada Other Total Wallboard $ 270 $ — $ — $ 68 $ 19 $ 357 Surfaces and industrial products 151 — — 23 7 181 Underlayment — 70 — 3 11 84 Building envelope and structural — 23 — 1 1 25 Ceiling tile and grid — — 121 12 8 141 Specialty ceilings — — 17 2 — 19 Other products 26 — — 5 17 48 Total product sales 447 93 138 114 63 855 Other miscellaneous sales (a) 65 12 1 7 2 87 Total sales before eliminations 512 105 139 121 65 942 Eliminations (30 ) (7 ) (15 ) (10 ) — (62 ) Total net sales $ 482 $ 98 $ 124 $ 111 $ 65 $ 880 Six months ended June 30, 2018 (millions) U.S. Wallboard and Surfaces U.S. Performance Materials U.S. Ceilings Canada Other Total Wallboard $ 490 $ — $ — $ 131 $ 37 $ 658 Surfaces and industrial products 296 — — 46 14 356 Underlayment — 135 — 5 20 160 Building envelope and structural — 41 — 1 1 43 Ceiling tile and grid — — 237 24 17 278 Specialty ceilings — — 33 4 — 37 Other products 50 — — 8 33 91 Total product sales 836 176 270 219 122 1,623 Other miscellaneous sales (a) 117 21 7 13 3 161 Total sales before eliminations 953 197 277 232 125 1,784 Eliminations (61 ) (13 ) (27 ) (17 ) — (118 ) Total net sales $ 892 $ 184 $ 250 $ 215 $ 125 $ 1,666 (a) Other miscellaneous sales primarily includes shipping and handling costs billed to customers.

Marketable Securities

Marketable Securities	6 Months Ended
	Jun. 30, 2018
Investments, Debt and Equity Securities [Abstract]
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 AOCI on our accompanying condensed consolidated balance sheets. Our investments in marketable securities consisted of the following: As of June 30, 2018 As of December 31, 2017 (millions) Amortized Cost Fair Value Amortized Cost Fair Value Corporate debt securities $ 70 $ 70 $ 68 $ 68 U.S. government and agency debt securities 1 1 6 6 Asset-backed debt securities 15 15 11 11 Certificates of deposit 9 9 13 13 Municipal debt securities 1 1 1 1 Total marketable securities $ 96 $ 96 $ 99 $ 99 The realized and unrealized gains and losses for the three and six months ended June 30, 2018 and 2017 were immaterial. Cost basis for securities sold are determined on a first-in-first-out basis. Contractual maturities of marketable securities as of June 30, 2018 were as follows: (millions) Amortized Cost Fair Value Due in 1 year or less $ 58 $ 58 Due in 1-5 years 38 38 Total marketable securities $ 96 $ 96 Actual maturities may differ from the contractual maturities because issuers of the securities may have the right to prepay them.

Debt

Debt	6 Months Ended
	Jun. 30, 2018
Debt Disclosure [Abstract]
Debt	Debt Total debt consisted of the following: (millions) June 30, December 31, 4.875% senior notes due 2027 $ 500 $ 500 5.5% senior notes due 2025 350 350 Industrial revenue bonds (due 2028 through 2034) 239 239 Total 1,089 1,089 Less: Unamortized debt issuance costs 11 11 Total $ 1,078 $ 1,078 SENIOR NOTES AND CREDIT FACILITY During the second quarter of 2017, we issued $500 million of 4.875% Senior Notes due 2027, referred to as our 4.875% Notes. The net proceeds from the issuance of these notes and cash on hand were used to fund the repurchase of our 7.75% Senior Notes due 2018, referred to as our 7.75% Notes, and all related costs and expenses. We deferred $7 million of debt issuance costs that are being amortized to interest expense over the term of the 4.875% Notes. We repurchased the 7.75% Notes through both a cash tender offer and a subsequent notice of redemption for aggregate consideration of $536 million , including premiums of $20 million and accrued interest of $16 million . In the three and six months ended June 30, 2017, we recorded a pre-tax loss on the early extinguishment of debt of $21 million . Also during the second quarter of 2017, we amended and restated our credit facility agreement. As a result, we recorded a pre-tax loss on extinguishment of debt of $1 million in the three and six months ended June 30, 2017. CREDIT FACILITY Our credit facility agreement has a maximum borrowing limit of $220 million and requires us to maintain a minimum fixed charge coverage ratio in the event excess availability falls below a minimum threshold. Our excess borrowing availability as of June 30, 2018 of $176 million exceeds this threshold, thus the requirement to maintain the minimum fixed charge coverage ratio is not applicable. As of June 30, 2018 , we were in compliance with the covenants contained in our credit facility. As of June 30, 2018 and during the quarter then-ended, there were no borrowings under the facility. Outstanding letters of credit totaled $22 million as of June 30, 2018 . OTHER INFORMATION (millions) June 30, December 31, Fair value of debt $ 1,115 $ 1,134 Accrued interest 12 12 The fair values of our debt were determined utilizing unadjusted prices from independent pricing services and are classified as Level 2. See Note 8, Fair Value Measurements, for further discussion on fair value measurements. The vendors’ methodologies utilize various forms of market data, including but not limited to, trade data, yield, spreads, bids and offers. We review the values provided by the independent pricing service for reasonableness by comparing the valuations received from the independent pricing service to valuations from at least one other observable source.

Derivative Instruments

Derivative Instruments	6 Months Ended
	Jun. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments We use derivative instruments to manage selected commodity price and foreign currency exposures as described below. We do not use derivative instruments for speculative trading purposes, and we typically do not hedge beyond five years. Cash flows from derivative instruments are included in operating activities in our condensed consolidated statements of cash flows. Gains and losses on contracts designated as cash flow hedges are reclassified into earnings when the underlying forecasted transactions affect earnings. For contracts designated as cash flow hedges, we reassess the probability of the underlying forecasted transactions occurring on a quarterly basis. Derivative Instruments Type Hedged Item Aggregate Notional Amount Contracts Maturing Through Commodity Natural gas swaps Purchases of natural gas 48 million mmBTUs* December 31, 2022 Foreign Exchange Forward contracts Purchases of products and services denominated in a foreign currency $119 million December 31, 2019 * - millions of British Thermal Units 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 June 30, 2018 , our derivatives were in a $11 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 $13 million of collateral posted with our counterparties related to our derivatives as of June 30, 2018 . Amounts paid as cash collateral are included in "Receivables" on our accompanying condensed 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 accompanying condensed consolidated balance sheets, based on their fair value as of the balance sheet date. FINANCIAL STATEMENT INFORMATION The following are the pre-tax effects of derivative instruments on the condensed consolidated statements of income and condensed consolidated statements of comprehensive income for the three months ended June 30, 2018 and 2017 . We recognized no gain or loss in income on derivatives not designated as hedging instruments for the three months ended June 30, 2018 and 2017. Amount of Gain or (Loss) Recognized in Other Comprehensive Income 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) 2018 2017 2018 2017 Derivatives in Cash Flow Hedging Relationships Commodity contracts $ — $ (1 ) Cost of products sold $ (2 ) $ (1 ) Foreign exchange contracts 2 (3 ) Cost of products sold — — Total $ 2 $ (4 ) $ (2 ) $ (1 ) The following are the pre-tax effects of derivative instruments on the condensed consolidated statements of income and condensed consolidated statements of comprehensive income for the six months ended June 30, 2018 and 2017 . Amount of Gain or (Loss) Recognized in Other Comprehensive Income 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) 2018 2017 2018 2017 Derivatives in Cash Flow Hedging Relationships Commodity contracts $ (3 ) $ (10 ) Cost of products sold $ (2 ) $ (1 ) Foreign exchange contracts 5 (3 ) Cost of products sold — — Total $ 2 $ (13 ) $ (2 ) $ (1 ) Location of Gain or (Loss) Recognized in Income on Derivatives Amount of Gain or (Loss) Recognized in Income on Derivatives (millions) 2018 2017 Derivatives Not Designated as Hedging Instruments Commodity contracts Cost of products sold $ — $ (1 ) Total $ — $ (1 ) For both commodity contracts and foreign exchange contracts, no ineffectiveness was recorded in the three and six months ended June 30, 2018 and 2017 . The following are the fair values of derivative instruments and the location on our accompanying condensed consolidated balance sheets as of June 30, 2018 and December 31, 2017 . Balance Sheet Location Fair Value Balance Sheet Location Fair Value (millions) 6/30/18 12/31/17 6/30/18 12/31/17 Derivatives in Cash Flow Hedging Relationships Commodity contracts Other current assets $ 1 $ 1 Accrued expenses $ 6 $ 6 Commodity contracts Other assets 2 1 Other liabilities 12 8 Foreign exchange contracts Other current assets 2 — Accrued expenses — 3 Foreign exchange contracts Other assets 2 — Other liabilities — — Total derivatives in cash flow hedging relationships $ 7 $ 2 $ 18 $ 17 Derivatives Not Designated as Hedging Instruments Commodity contracts Other current assets $ — $ — Accrued expenses $ — $ — Total derivatives not designated as hedging instruments $ — $ — $ — $ — Total derivatives Total assets $ 7 $ 2 Total liabilities $ 18 $ 17 As of June 30, 2018 , we had no derivatives designated as fair value hedges or net investment hedges.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Certain assets and liabilities are required to be recorded at fair value. There are three levels of inputs that may be used to measure fair value which are described below along with how USG derives fair value. Level Definition USG Valuation Method Level 1 Quoted prices for identical assets and liabilities in active markets Cash equivalents and equity mutual funds consist of money market funds that are valued based on quoted prices 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 Marketable securities, including certain cash equivalents, are valued using a "market value" approach. Values are based on quoted prices and other observable market inputs received from data providers. Derivatives are valued using the "income" approach such as discounted-cash-flow models and readily observable market data. The inputs for the valuation models are obtained from data providers and include end-of-period spot and forward natural gas prices, foreign currency exchange rates, natural gas price volatility and LIBOR and swap rates for discounting the cash flows implied from the derivative contracts. Level 3 Valuations derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable No level 3 investments. Our assets and liabilities measured at fair value on a recurring basis were as follows: Level 1 Level 2 Level 3 Total (millions) 6/30/18 12/31/17 6/30/18 12/31/17 6/30/18 12/31/17 6/30/18 12/31/17 Cash equivalents $ 44 $ 124 $ 33 $ 24 $ — $ — $ 77 $ 148 Equity mutual funds 6 6 — — — — 6 6 Marketable securities: Corporate debt securities — — 70 68 — — 70 68 U.S. government and agency debt securities — — 1 6 — — 1 6 Asset-backed debt securities — — 15 11 — — 15 11 Certificates of deposit — — 9 13 — — 9 13 Municipal debt securities — — 1 1 — — 1 1 Derivative assets — — 7 2 — — 7 2 Derivative liabilities — — (18 ) (17 ) — — (18 ) (17 )

Employee Retirement Plans

Employee Retirement Plans	6 Months Ended
	Jun. 30, 2018
Retirement Benefits [Abstract]
Employee Retirement Plans	Employee Retirement Plans The components of net pension and postretirement benefit costs are summarized in the following table: Three months ended June 30, Six months ended June 30, (millions) 2018 2017 2018 2017 Pension: Service cost of benefits earned $ 12 $ 11 $ 24 $ 21 Interest cost on projected benefit obligation 16 15 32 31 Expected return on plan assets (24 ) (23 ) (48 ) (46 ) Settlement — 20 — 20 Net amortization 8 5 16 10 Net pension cost $ 12 $ 28 $ 24 $ 36 Postretirement: Service cost of benefits earned $ 1 $ 1 $ 2 $ 2 Interest cost on projected benefit obligation 1 1 2 2 Net amortization (6 ) (6 ) (12 ) (12 ) Net postretirement benefit $ (4 ) $ (4 ) $ (8 ) $ (8 ) Service cost of benefits earned is included in "Costs of products sold" and "Selling and administrative expenses" on our condensed consolidated statements of income. The other components of net pension and postretirement costs are included in " Other (expense) income, net ". For the three and six months ended June 30, 2017, we recorded settlement expense of $20 million as the total lump sum distributions paid by the USG Corporation pension plan to both L&W employees and former USG employees during the first six months of 2017 exceeded the settlement threshold. Upon termination of their employment from USG, all L&W employees had the option to receive a lump sum benefit payment from the USG Corporation pension plan. For the benefits paid to terminated employees of L&W, we recorded a pre-tax loss of $13 million to "Income (loss) from discontinued operations" for the three and six months ended June 30, 2017. For the benefits paid to USG retirees, we recorded a pre-tax loss of $7 million to " Other (expense) income, net " for the three and six months ended June 30, 2017. During the first six months of 2018 , we made cash contributions of $50 million to the USG Corporation Retirement Plan Trust, $1 million to our domestic supplemental pension plan and $2 million to our pension plans in Canada. We expect to make total contributions to our pension plans in 2018 of approximately $60 million .

Share-Based Compensation

Share-Based Compensation	6 Months Ended
	Jun. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	Share-Based Compensation During the first six months of 2018 , we granted share-based compensation in the form of market share units, or MSUs, performance shares, and restricted stock units, or RSUs, to eligible participants under our 2016 Long-Term Incentive Plan. We recognize expense on all share-based grants over the service period, which is the shorter of the period until the employees’ retirement eligibility dates and the service period of the award for awards expected to vest. We record forfeitures as they occur. Awards granted during the first six months of 2018 , weighted average fair value, and assumptions used to determine fair value were as follows: MSUs Performance Shares RSUs Awards granted 428,574 103,819 44,000 Weighted average fair value (a) $ 34.22 $ 34.21 $ 36.92 Expected volatility (b) 32.62 % 32.61 % N/A Risk-free rate (c) 2.37 % 2.37 % N/A Expected term (in years) (d) 2.95 2.95 N/A Expected dividends — — N/A (a) Fair value of MSUs and performance shares is estimated on the date of grant using the Monte Carlo simulation utilizing the assumptions outlined above. Fair value of RSUs is equal to the closing price of our common stock on the date of grant. (b) The expected volatility rate is based on stock price history immediately prior to grant for a period commensurate with the expected term. (c) The risk-free rate is based on zero coupon U.S. government issues at the time of grant. (d) The expected term represents the period from the valuation date to the end of the performance period. Terms of the awards granted during the first six months of 2018 were as follows: MSUs Performance Shares RSUs Maximum shares/units earned Varies from 0% to 150% of the number of MSUs awarded depending on the actual performance of our stock price Varies from 0% to 200% of the number of performance shares awarded depending on the performance of our total stockholder return relative to the performance of the Dow Jones U.S. Construction and Materials Index (a) 100% Vesting Provisions Three-year performance period Three-year performance period Specified number of years from the grant date Vesting in the case of termination of employment due to death, disability, retirement or change in control during performance period (b) Pro-rated based on the number of full months employed in 2018 with awards issued at the end of the three-year period Pro-rated based on the number of full months employed during the performance period with awards issued at the end of the three-year period Varies Settlement Settled in common stock at the end of the performance or vesting period (a) Adjustments to the performance of the Dow Jones U.S. Construction and Materials Index may be made to reflect changes in the companies included in the index during the performance period. (b) Early vesting for MSUs, performance shares and RSUs in situations where there is a change in control also requires a related loss of employment or diminution of duties in certain circumstances. OTHER MSUs, performance shares, RSUs, and stock options that were not included in the computation of diluted earnings per share for those periods because their inclusion would be anti-dilutive were as follows: Three months ended June 30, Six months ended June 30, (millions) 2018 2017 2018 2017 MSUs, performance shares, RSUs and stock options — 0.7 — 0.9

Supplemental Balance Sheet Info

Supplemental Balance Sheet Information	6 Months Ended
	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Supplemental Balance Sheet Information	Supplemental Balance Sheet Information INVENTORIES Total inventories consisted of the following: (millions) June 30, 2018 December 31, 2017 Finished goods $ 153 $ 140 Work in progress 39 39 Raw materials 73 73 Total $ 265 $ 252 ACCRUED EXPENSES Accrued expenses consisted of the following: (millions) June 30, 2018 December 31, 2017 Self-insurance reserves $ 14 $ 12 Employee compensation 16 17 Interest 12 12 Derivatives 6 9 Pension and other postretirement benefits 17 17 Environmental 13 17 Other 52 51 Total $ 130 $ 135 ASSET RETIREMENT OBLIGATIONS Changes in the liability for asset retirement obligations, which are included in "Other liabilities" on our condensed consolidated balance sheets, consisted of the following: Six months ended June 30, (millions) 2018 2017 Balance as of January 1 $ 118 $ 113 Accretion expense 3 3 Liabilities settled (1 ) — Foreign currency translation (1 ) 1 Balance as of June 30 $ 119 $ 117 ASSET DISPOSITIONS In the second quarter of 2018, we recorded a gain of $13 million , or $9 million net of tax, on the sale of a surplus property. The pre-tax gain was recorded in cost of products sold within the U.S. Wallboard and Surfaces segment.

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2018
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity TREASURY STOCK Changes in treasury stock for the six months ended June 30, 2018 and 2017 were as follows: 2018 2017 (millions, except share data) Treasury Shares (000) Treasury Stock Treasury Shares (000) Treasury Stock Balance as of January 1 (5,571 ) $ (169 ) — $ — Repurchase of common stock for tax withholdings related to stock-based compensation (204 ) (7 ) (107 ) (3 ) Repurchase of common stock under share repurchase program (a) (2,156 ) (76 ) (3,161 ) (97 ) Stock reissuances 918 33 165 5 Balance as of June 30 (7,013 ) $ (219 ) (3,103 ) $ (95 ) (a) The Merger Agreement limits our ability to repurchase shares of our common stock, subject to certain exceptions, and share repurchases under the program will not continue so long as the Merger Agreement is in effect and has not been terminated. ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) Changes in the balances of each component of AOCI for the six months ended June 30, 2018 and 2017 were as follows: Derivatives Defined Benefit Plans Foreign Currency Translation AOCI (millions) 2018 2017 2018 2017 2018 2017 2018 2017 Balance as of January 1 $ 16 $ 27 $ (297 ) $ (246 ) $ (108 ) $ (166 ) $ (389 ) $ (385 ) Other comprehensive income (loss) before reclassifications, net of tax 2 (8 ) 3 3 (26 ) 48 (21 ) 43 Less: Amounts reclassified from AOCI, net of tax (2 ) (1 ) (3 ) (12 ) (4 ) — (9 ) (13 ) Net other comprehensive income (loss) 4 (7 ) 6 15 (22 ) 48 (12 ) 56 Balance as of June 30 $ 20 $ 20 $ (291 ) $ (231 ) $ (130 ) $ (118 ) $ (401 ) $ (329 ) Amounts reclassified from AOCI, net of tax, for the three and six months ended June 30, 2018 and 2017 , were as follows: Three months ended June 30, Six months ended June 30, (millions) 2018 2017 2018 2017 Derivatives Net reclassification from AOCI for cash flow hedges included in cost of products sold $ (2 ) $ (1 ) $ (2 ) $ (1 ) Less: Income tax benefit on reclassification from AOCI included in income tax expense — — — — Net amount reclassified from AOCI $ (2 ) $ (1 ) $ (2 ) $ (1 ) Defined Benefit Plans Net reclassification in AOCI for amortization of prior service cost included in other income, net $ (2 ) $ (7 ) $ (4 ) $ (7 ) Net reclassification from AOCI for amortization of prior service cost included in (loss) income from discontinued operations, net of tax — (8 ) — (8 ) Less: Income tax benefit on reclassification from AOCI included in income tax expense — (3 ) (1 ) (3 ) Net amount reclassified from AOCI $ (2 ) $ (12 ) $ (3 ) $ (12 ) Foreign Currency Translation Net reclassification from AOCI for translation gains realized upon the sale of foreign equity method investment included in other (expense) income, net $ (6 ) $ — $ (6 ) $ — Less: Income tax expense on reclassification from AOCI included in income tax expense (benefit) (2 ) — (2 ) — Net amount reclassified from AOCI $ (4 ) $ — $ (4 ) $ — We estimate that we will reclassify a net $2 million after-tax loss on derivatives from AOCI to earnings within the next 12 months.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Due to the timing of the enactment and the complexity involved in applying the provisions of the 2017 Tax Act, we made reasonable estimates of the effects and recorded provisional amounts in our financial statements as of December 31, 2017. The provisional effect on deferred tax assets and liabilities of the change in tax rates was recognized in earnings in the period ended December 31, 2017, which was when the change was enacted. As part of the 2017 Tax Act's change to a quasi-territorial system, a transition tax was imposed on our accumulated foreign earnings, partially offset by foreign tax credits, which was also recognized in the period ended December 31, 2017. The 2017 Tax Act made significant changes to how foreign tax credits may be realized to offset future tax liabilities. Further clarity may change our anticipated realization of our foreign tax credits. In addition, we may make an election to forgo the use of net operating losses, or NOLs, to offset the impact of the transition tax as allowed under the 2017 Tax Act. The estimate recorded as of December 31, 2017 continues to be our best estimate as of June 30, 2018 . As we collect and prepare necessary data and interpret the 2017 Tax Act and any additional guidance issued by the U.S. Treasury Department, the IRS, and other standard-setting bodies, we may make adjustments to the provisional amounts. Our income tax expense and effective tax rate for the three and six months ended June 30 were as follows: Three months ended June 30, Six months ended June 30, (dollars in millions) 2018 2017 2018 2017 Income tax expense $ 13 $ 20 $ 22 $ 49 Effective tax rate 18.3 % 30.3 % 19.0 % 32.7 % The income tax expense for all periods presented reflects taxes from federal, foreign, state and local jurisdictions. Our effective tax rates were lower than the U.S. statutory rate primarily because of earnings realized in countries that had lower statutory tax rates and our equity method income, which is presented net of tax. Our effective tax rate in the future will depend on, among other things, the portion of our profits earned within and outside the United States. As of June 30, 2018 , we had federal NOL carryforwards of approximately $429 million that are available to offset future federal taxable income and will expire in the years 2030 through 2032 , none of which are currently subject to Internal Revenue Code limitations under Section 382. In addition, as of that date, we had federal alternative minimum tax credit carryforwards of approximately $19 million that are available to reduce future regular federal income taxes with the full benefit being realized by 2022 as described in the 2017 Tax Act. We have foreign tax credit carryforwards of $224 million that are available to offset future federal taxable income and expire in the years 2022 through 2027. In order to fully realize these U.S. federal net deferred tax assets, taxable income of approximately $1.588 billion would need to be generated during the period before their expiration based on our interpretation of the 2017 Tax Act. As of June 30, 2018 , we had a deferred tax asset of $166 million related to our state NOLs and tax credit carryforwards. The NOLs will expire if unused in years 2018 through 2034. 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. As of June 30, 2018 , the valuation allowance against our deferred tax assets was $173 million , compared to $175 million at December 31, 2017. 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 June 30, 2018 , our annual U.S. federal NOL utilization would have been limited to approximately $139 million per year.

Litigation

Litigation	6 Months Ended
	Jun. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Litigation	Litigation WALLBOARD PRICING LAWSUITS In 2015, USG, our subsidiary United States Gypsum Company, our former subsidiary 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 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. The lawsuit was transferred to the United States District Court for the Eastern District of Pennsylvania under the title In re: Domestic Drywall Antitrust Litigation, MDL No. 2437. In the second quarter of 2016, the Court dismissed with prejudice the portions of the homebuilders’ complaint alleging a conspiracy in 2014 and 2015, ruling that there were insufficient factual allegations to allow such a claim to go forward. The homebuilders' claims alleging a conspiracy prior to 2014 have not been dismissed, and the case proceeds as to those claims. USG has agreed to defend and indemnify L&W Supply Corporation with regard to this matter. Beginning in the third quarter of 2013, class action lawsuits making similar allegations with regard to Canada were filed in Quebec, Ontario and British Columbia courts on behalf of purchasers of wallboard in Canada and naming USG, United States Gypsum Company, our Canadian subsidiary CGC Inc., or CGC, and other wallboard manufacturers as defendants. We believe that the cost, if any, of resolving the homebuilders’ lawsuit and Canadian class action litigation will not have a material effect on our results of operations, financial position or cash flows. ENVIRONMENTAL LITIGATION We are involved in environmental cleanups of property that we own or have owned. In addition, we have previously been notified by state and federal environmental protection agencies of possible involvement as one of numerous “potentially responsible parties” in certain Superfund sites in the United States to pay for some part of the cleanup of hazardous waste. In most of these sites, our involvement is expected to be minimal. As of June 30, 2018 and December 31, 2017 , we had accruals of $13 million and $17 million , respectively, 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.

Merger Agreement

Merger Agreement	6 Months Ended
	Jun. 30, 2018
Business Combinations [Abstract]
Merger Agreement	Acquisitions and Dispositions Acquisition of Ceilings Plus On November 30, 2017, we completed our acquisition of Ceilings Plus for $50 million , net of working capital adjustments. The addition of Ceilings Plus to our U.S. Ceilings segment expands our operations in the specialty ceilings markets. We finalized our valuation in the second quarter of 2018. The fair value of tangible assets acquired, less liabilities assumed, in connection with the Ceilings Plus acquisition was $15 million . The fair value of intangible assets acquired, which included customer relationships and trade names, totaled $20 million . The resulting goodwill recorded was $15 million and all is expected to be deductible for tax purposes. The goodwill resulting from this acquisition consists largely of Ceilings Plus' expected future product sales and synergies with the existing U.S. Ceilings product offerings. Discontinued Operations On October 31, 2016, we completed the sale of our L&W Supply, or L&W, distribution business to ABC Supply. For the three and six months ended June 30, 2017, we recorded a loss of $9 million , net of tax, for L&W to "Income (loss) from discontinued operations", which primarily reflected a pension settlement charge related to lump sum benefits paid to former employees of L&W. Upon the close of the sale, we entered into a supply agreement with L&W, and for the three and six months ended June 30, 2018 , we recorded sales of $122 million and $217 million , respectively, and cash inflows related to payments on trade receivables during those same periods of $107 million and $211 million , respectively. For the comparative periods in 2017, we recorded sales of $134 million and $265 million , respectively, and cash inflows related to payments on trade receivables of $143 million and $252 million , respectively. Merger Agreement On June 10, 2018, we entered into an Agreement and Plan of Merger, as it may be amended from time to time, or the Merger Agreement, with Knauf and World Cup Acquisition Corporation, a Delaware corporation and an indirect, wholly-owned subsidiary of Knauf, or Merger Sub. The Merger Agreement provides that, subject to the satisfaction of customary closing conditions, Merger Sub will be merged with and into USG, or the Merger, with USG continuing as the surviving corporation and an indirect, wholly-owned subsidiary of Knauf. Pursuant to the terms of the Merger Agreement, at the effective time of the Merger, each share of common stock, par value $0.10 , of USG issued and outstanding immediately prior to the effective time of the Merger (other than shares of common stock owned by Knauf and its subsidiaries, the Company and its subsidiaries and certain excluded holders) will be converted into the right to receive $43.50 in cash, without interest and subject to tax withholding. In addition, as contemplated by the Merger Agreement, USG is expected to declare a conditional special cash dividend of $0.50 per share, or the conditional special dividend, payable to holders of our common stock on the record date for the special meeting of stockholders held for the purpose, among other things, of adopting the Merger Agreement and the Merger, and will be paid following the certification of those results if the Merger Agreement is adopted by our stockholders. The Merger, which is currently expected to close in early 2019, is subject to the satisfaction or waiver of certain customary closing conditions, including, among others, adoption of the Merger Agreement by the affirmative vote of holders of at least 80% of outstanding shares of our common stock and receipt of certain regulatory approvals. The Merger Agreement contains certain termination rights for both USG and Knauf. If the Merger Agreement is terminated under certain specified circumstances, we will be required to pay Knauf a termination fee of $215 million (including under specified circumstances in connection with our entry into an agreement with respect to a superior proposal, as defined in the Merger Agreement). We have incurred $8 million and $9 million , pre-tax, of merger related costs for the three and six months ended June 30, 2018 , respectively, which are included in Selling and Administrative Expenses on our condensed consolidated statement of income.

Organization, Consolidation a23

Organization, Consolidation and Presentation of Financial Statements (Policies)	6 Months Ended
	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Segments	SEGMENTS Our reportable segments are determined considering both qualitative and quantitative metrics for aggregation of the product type within geographies for which discrete financial information is available. We have five reportable segments: U.S. Wallboard and Surfaces, U.S. Performance Materials, U.S. Ceilings, Canada, and USG Boral Building Products, or UBBP. Our U.S. Wallboard and Surfaces, U.S. Performance Materials and U.S. Ceilings reportable segments are identified based on products manufactured and marketed. Our Canada segment is a separately reportable segment, as while it has similar qualitative factors to U.S. operations, it has different quantitative metrics and, therefore, cannot be aggregated. Our operating segments in Mexico and Latin America are included in Other as reconciling items to our consolidated segments. This segment structure was effective for the quarter ended December 31, 2017. Our prior period results have been recast to reflect these changes and present comparative year over year information by segment.
Recently Adopted and Recently Issued Accounting Pronouncements	RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842),” which supersedes existing lease guidance to require lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by long-term leases and to disclose additional quantitative and qualitative information about leasing arrangements. Subsequently, the FASB has issued various ASUs to provide further clarification around certain aspects of Topic 842. We will adopt the new standard on January 1, 2019 using the modified retrospective approach. As a result of the new standard, we will implement a new lease accounting system, new processes and accounting policies. Further, we anticipate the adoption of ASU 2016-02 will have a significant impact to our condensed consolidated balance sheets and disclosures. We are currently finalizing our accounting policies, implementing a new leasing system, determining changes needed in current processes for lease accounting and verifying the completeness of our lease population and, thus, we are unable to quantify the financial statement impact at this time. RECENTLY ADOPTED ACCOUNTING PRONOUNCEMENTS We adopted Accounting Standard Update, or ASU, 2018-02, "Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income," in the first quarter of 2018. The ASU allows for the reclassification of stranded tax effects on items resulting from the Tax Cuts and Jobs Act, or the 2017 Tax Act, from accumulated other comprehensive income, or AOCI, to retained earnings. Tax effects unrelated to the 2017 Tax Act are released from AOCI using either the specific identification approach or the portfolio approach based on the nature of the underlying item. We elected not to reclassify the income tax effects of the 2017 Tax Act. We adopted ASU 2017-07, “Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost,” on January 1, 2018 using the practical expedient. This ASU required us to disaggregate and present current service cost along with other current compensation costs for employees while presenting other net benefit cost components below operating profit. In addition, only the service cost component of net benefit cost is eligible for capitalization in our inventory and fixed assets. We retrospectively adopted the presentation of service cost and prospectively adopted the capitalization of only service cost into inventory and fixed assets. The effect of the adoption of ASU 2017-07 on our condensed consolidated statements of income for the three and six months ended June 30, 2017 was as follows. (millions) Three months ended June 30, 2017 Six months ended June 30, 2017 As Restated Adjustment for Adoption of ASU 2017-07 As Previously Reported As Restated Adjustment for Adoption of ASU 2017-07 As Previously Reported Gross profit $ 168 $ — $ 168 $ 327 $ (5 ) $ 332 Operating profit 95 (1 ) 96 179 (8 ) 187 Other income, net (2 ) 1 (3 ) 4 8 (4 ) Net income 36 — 36 91 — 91 We adopted ASU 2014-09, “Revenue from Contracts with Customers (Topic 606),” and all related amendments on January 1, 2018 using the modified retrospective method using practical expedients. Topic 606 supersedes the revenue recognition requirements in "Revenue Recognition (Topic 605)" and requires entities to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. Upon adoption, we recorded an increase of $2 million to our opening balance of retained earnings for the cumulative effect of adopting Topic 606. The adjustment related to a change to the point in time at which we record revenue for most customers. Prior period amounts have not been restated and continue to be reported under the legacy accounting guidance of Topic 605. As of and for the three and six months ended June 30, 2018, the impact of applying Topic 606 as compared to applying Topic 605 is immaterial to our financial statements. In addition to our cumulative effect adjustment, our adoption of Topic 606 resulted in additional quantitative disclosure of revenue by product and in the modification of certain significant accounting policies. See Note 4 , Segments, for our revenue disaggregated by product and the revised polices below.
Revenue Recognition and Shipping and Handling Costs	Revenue Recognition We recognize revenue upon transfer of control of our products to the customer which generally occurs upon shipment. We enter into agreements with customers to offer rebates, generally based on achievement of specified sales levels and various marketing allowances that are common industry practice. Reductions to revenue for customer programs and incentive offerings, including promotions and other volume-based incentives, are estimated using the most likely amount method and recorded in the period in which the sale occurs. Provisions for early payment discounts are accrued in the same period in which the sale occurs. We do not have any material payment terms as payment is received shortly after the point of sale. We pay commissions to third parties to obtain contracts. As these contracts are less than one year, these costs are expensed as incurred. Shipping and Handling Costs We include shipping and handling costs billed to customers in net sales. We account for related costs as fulfillment activities and present the costs in cost of products sold when control of our products transfers to the customer.

Organization, Consolidation a24

Organization, Consolidation and Presentation of Financial Statements (Tables)	6 Months Ended
	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of New Accounting Pronouncements	The effect of the adoption of ASU 2017-07 on our condensed consolidated statements of income for the three and six months ended June 30, 2017 was as follows. (millions) Three months ended June 30, 2017 Six months ended June 30, 2017 As Restated Adjustment for Adoption of ASU 2017-07 As Previously Reported As Restated Adjustment for Adoption of ASU 2017-07 As Previously Reported Gross profit $ 168 $ — $ 168 $ 327 $ (5 ) $ 332 Operating profit 95 (1 ) 96 179 (8 ) 187 Other income, net (2 ) 1 (3 ) 4 8 (4 ) Net income 36 — 36 91 — 91

Equity Method Investments (Tabl

Equity Method Investments (Tables)	6 Months Ended
	Jun. 30, 2018
Equity Method Investments and Joint Ventures [Abstract]
Summarized Financial Information	Equity method investments as of June 30, 2018 and December 31, 2017 , were as follows: June 30, 2018 December 31, 2017 (dollars in millions) Carrying Value Ownership Percentage Carrying Value Ownership Percentage USG Boral Building Products $ 664 50% $ 679 50% Other equity method investments 2 50% 7 33% - 50% Total equity method investments $ 666 $ 686 Summarized financial information for UBBP is as follows: Three months ended June 30, Six months ended June 30, (millions) 2018 2017 2018 2017 USG Boral Building Products Net sales $ 297 $ 287 $ 584 $ 563 Gross profit 83 91 162 177 Operating profit 31 40 59 75 Income from continuing operations before income taxes 35 44 67 82 Net income 25 28 45 54 Net income attributable to USG Boral Building Products 24 28 43 53 USG share of income from investment accounted for using the equity method 12 14 21 27
Translation Gain or Losses in Other Comprehensive Income	Translation gains or losses recorded in other comprehensive income were as follows: Three months ended June 30, Six months ended June 30, (millions) 2018 2017 2018 2017 Translation (loss) gain $ (24 ) $ (1 ) $ (21 ) $ 23

Segments (Tables)

Segments (Tables)	6 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
Net sales and operating profit (loss) by segment	Segment results for our U.S. Wallboard and Surfaces, U.S. Performance Materials, U.S. Ceilings and Canada segments were as follows: Three months ended June 30, Six months ended June 30, (millions) 2018 2017 2018 2017 Net Sales : U.S. Wallboard and Surfaces $ 512 $ 482 $ 953 $ 951 U.S. Performance Materials 105 100 197 186 U.S. Ceilings 139 118 277 230 Canada 121 104 232 200 Other 65 59 125 115 Eliminations (62 ) (52 ) (118 ) (104 ) Total $ 880 $ 811 $ 1,666 $ 1,578 Operating Profit (Loss) : U.S. Wallboard and Surfaces $ 81 $ 78 $ 130 $ 157 U.S. Performance Materials (6 ) 8 (5 ) 14 U.S. Ceilings 23 23 42 43 Canada 8 2 10 4 Other 4 1 8 2 Corporate (35 ) (17 ) (64 ) (41 ) Total $ 75 $ 95 $ 121 $ 179 Net sales disaggregated by product type were as follows: Three months ended June 30, 2018 (millions) U.S. Wallboard and Surfaces U.S. Performance Materials U.S. Ceilings Canada Other Total Wallboard $ 270 $ — $ — $ 68 $ 19 $ 357 Surfaces and industrial products 151 — — 23 7 181 Underlayment — 70 — 3 11 84 Building envelope and structural — 23 — 1 1 25 Ceiling tile and grid — — 121 12 8 141 Specialty ceilings — — 17 2 — 19 Other products 26 — — 5 17 48 Total product sales 447 93 138 114 63 855 Other miscellaneous sales (a) 65 12 1 7 2 87 Total sales before eliminations 512 105 139 121 65 942 Eliminations (30 ) (7 ) (15 ) (10 ) — (62 ) Total net sales $ 482 $ 98 $ 124 $ 111 $ 65 $ 880 Six months ended June 30, 2018 (millions) U.S. Wallboard and Surfaces U.S. Performance Materials U.S. Ceilings Canada Other Total Wallboard $ 490 $ — $ — $ 131 $ 37 $ 658 Surfaces and industrial products 296 — — 46 14 356 Underlayment — 135 — 5 20 160 Building envelope and structural — 41 — 1 1 43 Ceiling tile and grid — — 237 24 17 278 Specialty ceilings — — 33 4 — 37 Other products 50 — — 8 33 91 Total product sales 836 176 270 219 122 1,623 Other miscellaneous sales (a) 117 21 7 13 3 161 Total sales before eliminations 953 197 277 232 125 1,784 Eliminations (61 ) (13 ) (27 ) (17 ) — (118 ) Total net sales $ 892 $ 184 $ 250 $ 215 $ 125 $ 1,666 (a) Other miscellaneous sales primarily includes shipping and handling costs billed to customers.

Marketable Securities (Tables)

Marketable Securities (Tables)	6 Months Ended
	Jun. 30, 2018
Investments, Debt and Equity Securities [Abstract]
Investments in marketable securities	Our investments in marketable securities consisted of the following: As of June 30, 2018 As of December 31, 2017 (millions) Amortized Cost Fair Value Amortized Cost Fair Value Corporate debt securities $ 70 $ 70 $ 68 $ 68 U.S. government and agency debt securities 1 1 6 6 Asset-backed debt securities 15 15 11 11 Certificates of deposit 9 9 13 13 Municipal debt securities 1 1 1 1 Total marketable securities $ 96 $ 96 $ 99 $ 99
Contractual maturities of marketable securities	Contractual maturities of marketable securities as of June 30, 2018 were as follows: (millions) Amortized Cost Fair Value Due in 1 year or less $ 58 $ 58 Due in 1-5 years 38 38 Total marketable securities $ 96 $ 96

Debt (Tables)

Debt (Tables)	6 Months Ended
	Jun. 30, 2018
Debt Disclosure [Abstract]
Schedule of long-term debt instruments	Total debt consisted of the following: (millions) June 30, December 31, 4.875% senior notes due 2027 $ 500 $ 500 5.5% senior notes due 2025 350 350 Industrial revenue bonds (due 2028 through 2034) 239 239 Total 1,089 1,089 Less: Unamortized debt issuance costs 11 11 Total $ 1,078 $ 1,078
Other debt disclosure	OTHER INFORMATION (millions) June 30, December 31, Fair value of debt $ 1,115 $ 1,134 Accrued interest 12 12

Derivative Instruments (Tables)

Derivative Instruments (Tables)	6 Months Ended
	Jun. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of notional amounts of outstanding derivative positions	Derivative Instruments Type Hedged Item Aggregate Notional Amount Contracts Maturing Through Commodity Natural gas swaps Purchases of natural gas 48 million mmBTUs* December 31, 2022 Foreign Exchange Forward contracts Purchases of products and services denominated in a foreign currency $119 million December 31, 2019 * - millions of British Thermal Units
Pretax effects of derivative instruments on consolidated statements of operations	The following are the pre-tax effects of derivative instruments on the condensed consolidated statements of income and condensed consolidated statements of comprehensive income for the three months ended June 30, 2018 and 2017 . We recognized no gain or loss in income on derivatives not designated as hedging instruments for the three months ended June 30, 2018 and 2017. Amount of Gain or (Loss) Recognized in Other Comprehensive Income 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) 2018 2017 2018 2017 Derivatives in Cash Flow Hedging Relationships Commodity contracts $ — $ (1 ) Cost of products sold $ (2 ) $ (1 ) Foreign exchange contracts 2 (3 ) Cost of products sold — — Total $ 2 $ (4 ) $ (2 ) $ (1 ) The following are the pre-tax effects of derivative instruments on the condensed consolidated statements of income and condensed consolidated statements of comprehensive income for the six months ended June 30, 2018 and 2017 . Amount of Gain or (Loss) Recognized in Other Comprehensive Income 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) 2018 2017 2018 2017 Derivatives in Cash Flow Hedging Relationships Commodity contracts $ (3 ) $ (10 ) Cost of products sold $ (2 ) $ (1 ) Foreign exchange contracts 5 (3 ) Cost of products sold — — Total $ 2 $ (13 ) $ (2 ) $ (1 ) Location of Gain or (Loss) Recognized in Income on Derivatives Amount of Gain or (Loss) Recognized in Income on Derivatives (millions) 2018 2017 Derivatives Not Designated as Hedging Instruments Commodity contracts Cost of products sold $ — $ (1 ) Total $ — $ (1 )
Fair values of derivative instruments and the location on the consolidated balance sheets	The following are the fair values of derivative instruments and the location on our accompanying condensed consolidated balance sheets as of June 30, 2018 and December 31, 2017 . Balance Sheet Location Fair Value Balance Sheet Location Fair Value (millions) 6/30/18 12/31/17 6/30/18 12/31/17 Derivatives in Cash Flow Hedging Relationships Commodity contracts Other current assets $ 1 $ 1 Accrued expenses $ 6 $ 6 Commodity contracts Other assets 2 1 Other liabilities 12 8 Foreign exchange contracts Other current assets 2 — Accrued expenses — 3 Foreign exchange contracts Other assets 2 — Other liabilities — — Total derivatives in cash flow hedging relationships $ 7 $ 2 $ 18 $ 17 Derivatives Not Designated as Hedging Instruments Commodity contracts Other current assets $ — $ — Accrued expenses $ — $ — Total derivatives not designated as hedging instruments $ — $ — $ — $ — Total derivatives Total assets $ 7 $ 2 Total liabilities $ 18 $ 17

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2018
Fair Value Disclosures [Abstract]
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: Level 1 Level 2 Level 3 Total (millions) 6/30/18 12/31/17 6/30/18 12/31/17 6/30/18 12/31/17 6/30/18 12/31/17 Cash equivalents $ 44 $ 124 $ 33 $ 24 $ — $ — $ 77 $ 148 Equity mutual funds 6 6 — — — — 6 6 Marketable securities: Corporate debt securities — — 70 68 — — 70 68 U.S. government and agency debt securities — — 1 6 — — 1 6 Asset-backed debt securities — — 15 11 — — 15 11 Certificates of deposit — — 9 13 — — 9 13 Municipal debt securities — — 1 1 — — 1 1 Derivative assets — — 7 2 — — 7 2 Derivative liabilities — — (18 ) (17 ) — — (18 ) (17 )

Employee Retirement Plans (Tabl

Employee Retirement Plans (Tables)	6 Months Ended
	Jun. 30, 2018
Retirement Benefits [Abstract]
Components of net pension and postretirement benefits costs	The components of net pension and postretirement benefit costs are summarized in the following table: Three months ended June 30, Six months ended June 30, (millions) 2018 2017 2018 2017 Pension: Service cost of benefits earned $ 12 $ 11 $ 24 $ 21 Interest cost on projected benefit obligation 16 15 32 31 Expected return on plan assets (24 ) (23 ) (48 ) (46 ) Settlement — 20 — 20 Net amortization 8 5 16 10 Net pension cost $ 12 $ 28 $ 24 $ 36 Postretirement: Service cost of benefits earned $ 1 $ 1 $ 2 $ 2 Interest cost on projected benefit obligation 1 1 2 2 Net amortization (6 ) (6 ) (12 ) (12 ) Net postretirement benefit $ (4 ) $ (4 ) $ (8 ) $ (8 )

Share-Based Compensation (Table

Share-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of awards granted during the period	Awards granted during the first six months of 2018 , weighted average fair value, and assumptions used to determine fair value were as follows: MSUs Performance Shares RSUs Awards granted 428,574 103,819 44,000 Weighted average fair value (a) $ 34.22 $ 34.21 $ 36.92 Expected volatility (b) 32.62 % 32.61 % N/A Risk-free rate (c) 2.37 % 2.37 % N/A Expected term (in years) (d) 2.95 2.95 N/A Expected dividends — — N/A (a) Fair value of MSUs and performance shares is estimated on the date of grant using the Monte Carlo simulation utilizing the assumptions outlined above. Fair value of RSUs is equal to the closing price of our common stock on the date of grant. (b) The expected volatility rate is based on stock price history immediately prior to grant for a period commensurate with the expected term. (c) The risk-free rate is based on zero coupon U.S. government issues at the time of grant. (d) The expected term represents the period from the valuation date to the end of the performance period. Terms of the awards granted during the first six months of 2018 were as follows: MSUs Performance Shares RSUs Maximum shares/units earned Varies from 0% to 150% of the number of MSUs awarded depending on the actual performance of our stock price Varies from 0% to 200% of the number of performance shares awarded depending on the performance of our total stockholder return relative to the performance of the Dow Jones U.S. Construction and Materials Index (a) 100% Vesting Provisions Three-year performance period Three-year performance period Specified number of years from the grant date Vesting in the case of termination of employment due to death, disability, retirement or change in control during performance period (b) Pro-rated based on the number of full months employed in 2018 with awards issued at the end of the three-year period Pro-rated based on the number of full months employed during the performance period with awards issued at the end of the three-year period Varies Settlement Settled in common stock at the end of the performance or vesting period (a) Adjustments to the performance of the Dow Jones U.S. Construction and Materials Index may be made to reflect changes in the companies included in the index during the performance period. (b) Early vesting for MSUs, performance shares and RSUs in situations where there is a change in control also requires a related loss of employment or diminution of duties in certain circumstances.
Schedule of antidilutive securities excluded from computation of earnings per share	MSUs, performance shares, RSUs, and stock options that were not included in the computation of diluted earnings per share for those periods because their inclusion would be anti-dilutive were as follows: Three months ended June 30, Six months ended June 30, (millions) 2018 2017 2018 2017 MSUs, performance shares, RSUs and stock options — 0.7 — 0.9

Supplemental Balance Sheet In33

Supplemental Balance Sheet Information (Tables)	6 Months Ended
	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of inventories	Total inventories consisted of the following: (millions) June 30, 2018 December 31, 2017 Finished goods $ 153 $ 140 Work in progress 39 39 Raw materials 73 73 Total $ 265 $ 252
Schedule of accrued expenses	Accrued expenses consisted of the following: (millions) June 30, 2018 December 31, 2017 Self-insurance reserves $ 14 $ 12 Employee compensation 16 17 Interest 12 12 Derivatives 6 9 Pension and other postretirement benefits 17 17 Environmental 13 17 Other 52 51 Total $ 130 $ 135
Changes in the liability for asset retirement obligations	Changes in the liability for asset retirement obligations, which are included in "Other liabilities" on our condensed consolidated balance sheets, consisted of the following: Six months ended June 30, (millions) 2018 2017 Balance as of January 1 $ 118 $ 113 Accretion expense 3 3 Liabilities settled (1 ) — Foreign currency translation (1 ) 1 Balance as of June 30 $ 119 $ 117

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2018
Equity [Abstract]
Schedule of Treasury Stock	Changes in treasury stock for the six months ended June 30, 2018 and 2017 were as follows: 2018 2017 (millions, except share data) Treasury Shares (000) Treasury Stock Treasury Shares (000) Treasury Stock Balance as of January 1 (5,571 ) $ (169 ) — $ — Repurchase of common stock for tax withholdings related to stock-based compensation (204 ) (7 ) (107 ) (3 ) Repurchase of common stock under share repurchase program (a) (2,156 ) (76 ) (3,161 ) (97 ) Stock reissuances 918 33 165 5 Balance as of June 30 (7,013 ) $ (219 ) (3,103 ) $ (95 ) (a) The Merger Agreement limits our ability to repurchase shares of our common stock, subject to certain exceptions, and share repurchases under the program will not continue so long as the Merger Agreement is in effect and has not been terminated.
Changes in the balances of each component of AOCI	Changes in the balances of each component of AOCI for the six months ended June 30, 2018 and 2017 were as follows: Derivatives Defined Benefit Plans Foreign Currency Translation AOCI (millions) 2018 2017 2018 2017 2018 2017 2018 2017 Balance as of January 1 $ 16 $ 27 $ (297 ) $ (246 ) $ (108 ) $ (166 ) $ (389 ) $ (385 ) Other comprehensive income (loss) before reclassifications, net of tax 2 (8 ) 3 3 (26 ) 48 (21 ) 43 Less: Amounts reclassified from AOCI, net of tax (2 ) (1 ) (3 ) (12 ) (4 ) — (9 ) (13 ) Net other comprehensive income (loss) 4 (7 ) 6 15 (22 ) 48 (12 ) 56 Balance as of June 30 $ 20 $ 20 $ (291 ) $ (231 ) $ (130 ) $ (118 ) $ (401 ) $ (329 )
Amounts reclassified from AOCI, net of tax	Amounts reclassified from AOCI, net of tax, for the three and six months ended June 30, 2018 and 2017 , were as follows: Three months ended June 30, Six months ended June 30, (millions) 2018 2017 2018 2017 Derivatives Net reclassification from AOCI for cash flow hedges included in cost of products sold $ (2 ) $ (1 ) $ (2 ) $ (1 ) Less: Income tax benefit on reclassification from AOCI included in income tax expense — — — — Net amount reclassified from AOCI $ (2 ) $ (1 ) $ (2 ) $ (1 ) Defined Benefit Plans Net reclassification in AOCI for amortization of prior service cost included in other income, net $ (2 ) $ (7 ) $ (4 ) $ (7 ) Net reclassification from AOCI for amortization of prior service cost included in (loss) income from discontinued operations, net of tax — (8 ) — (8 ) Less: Income tax benefit on reclassification from AOCI included in income tax expense — (3 ) (1 ) (3 ) Net amount reclassified from AOCI $ (2 ) $ (12 ) $ (3 ) $ (12 ) Foreign Currency Translation Net reclassification from AOCI for translation gains realized upon the sale of foreign equity method investment included in other (expense) income, net $ (6 ) $ — $ (6 ) $ — Less: Income tax expense on reclassification from AOCI included in income tax expense (benefit) (2 ) — (2 ) — Net amount reclassified from AOCI $ (4 ) $ — $ (4 ) $ —

Income Taxes (Tables)

Income Taxes (Tables)	6 Months Ended
	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	Our income tax expense and effective tax rate for the three and six months ended June 30 were as follows: Three months ended June 30, Six months ended June 30, (dollars in millions) 2018 2017 2018 2017 Income tax expense $ 13 $ 20 $ 22 $ 49 Effective tax rate 18.3 % 30.3 % 19.0 % 32.7 %

Organization, Consolidation a36

Organization, Consolidation and Presentation of Financial Statements - Segments (Details)	6 Months Ended
	Jun. 30, 2018segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of reportable segments	5

Organization, Consolidation a37

Organization, Consolidation and Presentation of Financial Statements - Presentation of Financial Statements (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Gross profit	$ 184	$ 168	$ 323	$ 327
Operating profit	75	95	121	179
Other (expense) income, net	(3)	(2)	0	4
Net income	58	36	95	91
Retained earnings (accumulated deficit)	$ (572)		$ (572)		$ (669)
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained earnings (accumulated deficit)					$ 2
Adjustment | Accounting Standards Update 2017-07
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Gross profit		0		(5)
Operating profit		(1)		(8)
Other (expense) income, net		1		8
Net income		0		0
As Previously Reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Gross profit		168		332
Operating profit		96		187
Other (expense) income, net		(3)		(4)
Net income		$ 36		$ 91

Acquisitions and Dispositions -

Acquisitions and Dispositions - Acquisitions (Details) - Ceilings Plus $ in Millions	Nov. 30, 2017USD ($)
Business Acquisition [Line Items]
Purchase price of acquisition	$ 50
Fair value of tangible assets acquired, less liabilities assumed	15
Fair value of intangible assets acquired	20
Goodwill, acquired	$ 15

Acquisitions and Dispositions39

Acquisitions and Dispositions - Dispositions (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on disposition, net of tax	$ (9)
L&W Supply
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on disposition, net of tax		$ 9		$ 9
Sales to discontinued operations previously eliminated in consolidation	122	134	$ 217	265
Cash consideration for discontinued operation	$ 107	$ 143	$ 211	$ 252

Equity Method Investments - Sch

Equity Method Investments - Schedule of Equity Method Investments (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Carrying Value	$ 666	$ 686
USG Boral Building Products
Schedule of Equity Method Investments [Line Items]
Carrying Value	$ 664	$ 679
Ownership Percentage	50.00%	50.00%
Other equity method investments
Schedule of Equity Method Investments [Line Items]
Carrying Value	$ 2	$ 7
Other equity method investments | Minimum
Schedule of Equity Method Investments [Line Items]
Ownership Percentage		33.00%
Other equity method investments | Maximum
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	50.00%	50.00%

Equity Method Investments - Nar

Equity Method Investments - Narrative (Details) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Dividends received from equity method investments		$ 16,000,000	$ 23,000,000
Equity method investment, performance target		5 years
Interest of joint venture	33.00%
Sale of interest in joint venture	$ 3,000,000
Loss on sale of investment	8,000,000
Loss on sale of investments, net of tax	5,000,000
USG Boral Building Products
Schedule of Equity Method Investments [Line Items]
Loan receivable from related party	$ 13,000,000	$ 13,000,000		$ 13,000,000
USG Boral Building Products
Schedule of Equity Method Investments [Line Items]
Joint venture (percentage)	50.00%	50.00%		50.00%
Dividends received from equity method investments	$ 16,000,000
Undistributed earnings	66,000,000	$ 66,000,000
Contingent consideration for second performance period	$ 50,000,000	$ 50,000,000

Equity Method Investments - Tra

Equity Method Investments - Translation Gains or Losses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Schedule of Equity Method Investments [Line Items]
Translation (loss) gain	$ (38)	$ 8	$ (26)	$ 48
USG Boral Building Products
Schedule of Equity Method Investments [Line Items]
Translation (loss) gain	$ (24)	$ (1)	$ (21)	$ 23

Equity Method Investments - Sum

Equity Method Investments - Summarized Financial Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Schedule of Equity Method Investments [Line Items]
USG share of income from investment accounted for using the equity method			$ 21	$ 27
USG Boral Building Products
Schedule of Equity Method Investments [Line Items]
Net sales	$ 297	$ 287	584	563
Gross profit	83	91	162	177
Operating profit	31	40	59	75
Income from continuing operations before income taxes	35	44	67	82
Net income	25	28	45	54
Net income attributable to USG Boral Building Products	24	28	43	53
USG share of income from investment accounted for using the equity method	$ 12	$ 14	$ 21	$ 27

Segments (Details)

Segments (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2018USD ($)segment	Jun. 30, 2017USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment			5
Net Sales:
Total net sales	$ 880	$ 811	$ 1,666	$ 1,578
Operating Profit (Loss):
Total	75	95	121	179
U.S. Wallboard and Surfaces
Net Sales:
Total net sales	482		892
U.S. Performance Materials
Net Sales:
Total net sales	98		184
U.S. Ceilings
Net Sales:
Total net sales	124		250
Canada
Net Sales:
Total net sales	111		215
Other
Net Sales:
Total net sales	65		125
Operating segments
Net Sales:
Total net sales	942		1,784
Operating segments | Wallboard
Net Sales:
Total net sales	357		658
Operating segments | Surfaces and industrial products
Net Sales:
Total net sales	181		356
Operating segments | Underlayment
Net Sales:
Total net sales	84		160
Operating segments | Building envelope and structural
Net Sales:
Total net sales	25		43
Operating segments | Ceiling tile and grid
Net Sales:
Total net sales	141		278
Operating segments | Specialty ceilings
Net Sales:
Total net sales	19		37
Operating segments | Other products
Net Sales:
Total net sales	48		91
Operating segments | Total product sales
Net Sales:
Total net sales	855		1,623
Operating segments | Other miscellaneous sales
Net Sales:
Total net sales	87		161
Operating segments | U.S. Wallboard and Surfaces
Net Sales:
Total net sales	512	482	953	951
Operating Profit (Loss):
Total	81	78	130	157
Operating segments | U.S. Wallboard and Surfaces | Wallboard
Net Sales:
Total net sales	270		490
Operating segments | U.S. Wallboard and Surfaces | Surfaces and industrial products
Net Sales:
Total net sales	151		296
Operating segments | U.S. Wallboard and Surfaces | Underlayment
Net Sales:
Total net sales	0		0
Operating segments | U.S. Wallboard and Surfaces | Building envelope and structural
Net Sales:
Total net sales	0		0
Operating segments | U.S. Wallboard and Surfaces | Ceiling tile and grid
Net Sales:
Total net sales	0		0
Operating segments | U.S. Wallboard and Surfaces | Specialty ceilings
Net Sales:
Total net sales	0		0
Operating segments | U.S. Wallboard and Surfaces | Other products
Net Sales:
Total net sales	26		50
Operating segments | U.S. Wallboard and Surfaces | Total product sales
Net Sales:
Total net sales	447		836
Operating segments | U.S. Wallboard and Surfaces | Other miscellaneous sales
Net Sales:
Total net sales	65		117
Operating segments | U.S. Performance Materials
Net Sales:
Total net sales	105	100	197	186
Operating Profit (Loss):
Total	(6)	8	(5)	14
Operating segments | U.S. Performance Materials | Wallboard
Net Sales:
Total net sales	0		0
Operating segments | U.S. Performance Materials | Surfaces and industrial products
Net Sales:
Total net sales	0		0
Operating segments | U.S. Performance Materials | Underlayment
Net Sales:
Total net sales	70		135
Operating segments | U.S. Performance Materials | Building envelope and structural
Net Sales:
Total net sales	23		41
Operating segments | U.S. Performance Materials | Ceiling tile and grid
Net Sales:
Total net sales	0		0
Operating segments | U.S. Performance Materials | Specialty ceilings
Net Sales:
Total net sales	0		0
Operating segments | U.S. Performance Materials | Other products
Net Sales:
Total net sales	0		0
Operating segments | U.S. Performance Materials | Total product sales
Net Sales:
Total net sales	93		176
Operating segments | U.S. Performance Materials | Other miscellaneous sales
Net Sales:
Total net sales	12		21
Operating segments | U.S. Ceilings
Net Sales:
Total net sales	139	118	277	230
Operating Profit (Loss):
Total	23	23	42	43
Operating segments | U.S. Ceilings | Wallboard
Net Sales:
Total net sales	0		0
Operating segments | U.S. Ceilings | Surfaces and industrial products
Net Sales:
Total net sales	0		0
Operating segments | U.S. Ceilings | Underlayment
Net Sales:
Total net sales	0		0
Operating segments | U.S. Ceilings | Building envelope and structural
Net Sales:
Total net sales	0		0
Operating segments | U.S. Ceilings | Ceiling tile and grid
Net Sales:
Total net sales	121		237
Operating segments | U.S. Ceilings | Specialty ceilings
Net Sales:
Total net sales	17		33
Operating segments | U.S. Ceilings | Other products
Net Sales:
Total net sales	0		0
Operating segments | U.S. Ceilings | Total product sales
Net Sales:
Total net sales	138		270
Operating segments | U.S. Ceilings | Other miscellaneous sales
Net Sales:
Total net sales	1		7
Operating segments | Canada
Net Sales:
Total net sales	121	104	232	200
Operating Profit (Loss):
Total	8	2	10	4
Operating segments | Canada | Wallboard
Net Sales:
Total net sales	68		131
Operating segments | Canada | Surfaces and industrial products
Net Sales:
Total net sales	23		46
Operating segments | Canada | Underlayment
Net Sales:
Total net sales	3		5
Operating segments | Canada | Building envelope and structural
Net Sales:
Total net sales	1		1
Operating segments | Canada | Ceiling tile and grid
Net Sales:
Total net sales	12		24
Operating segments | Canada | Specialty ceilings
Net Sales:
Total net sales	2		4
Operating segments | Canada | Other products
Net Sales:
Total net sales	5		8
Operating segments | Canada | Total product sales
Net Sales:
Total net sales	114		219
Operating segments | Canada | Other miscellaneous sales
Net Sales:
Total net sales	7		13
Operating segments | Other
Net Sales:
Total net sales	65	59	125	115
Operating Profit (Loss):
Total	4	1	8	2
Operating segments | Other | Wallboard
Net Sales:
Total net sales	19		37
Operating segments | Other | Surfaces and industrial products
Net Sales:
Total net sales	7		14
Operating segments | Other | Underlayment
Net Sales:
Total net sales	11		20
Operating segments | Other | Building envelope and structural
Net Sales:
Total net sales	1		1
Operating segments | Other | Ceiling tile and grid
Net Sales:
Total net sales	8		17
Operating segments | Other | Specialty ceilings
Net Sales:
Total net sales	0		0
Operating segments | Other | Other products
Net Sales:
Total net sales	17		33
Operating segments | Other | Total product sales
Net Sales:
Total net sales	63		122
Operating segments | Other | Other miscellaneous sales
Net Sales:
Total net sales	2		3
Eliminations
Net Sales:
Total net sales	(62)	(52)	(118)	(104)
Eliminations | U.S. Wallboard and Surfaces
Net Sales:
Total net sales	(30)		(61)
Eliminations | U.S. Performance Materials
Net Sales:
Total net sales	(7)		(13)
Eliminations | U.S. Ceilings
Net Sales:
Total net sales	(15)		(27)
Eliminations | Canada
Net Sales:
Total net sales	(10)		(17)
Eliminations | Other
Net Sales:
Total net sales	0		0
Corporate
Operating Profit (Loss):
Total	$ (35)	$ (17)	$ (64)	$ (41)

Marketable Securities - Reporte

Marketable Securities - Reported on AOCI (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Marketable Securities [Line Items]
Amortized Cost	$ 96	$ 99
Fair Value	96	99
Corporate debt securities
Marketable Securities [Line Items]
Amortized Cost	70	68
Fair Value	70	68
U.S. government and agency debt securities
Marketable Securities [Line Items]
Amortized Cost	1	6
Fair Value	1	6
Asset-backed debt securities
Marketable Securities [Line Items]
Amortized Cost	15	11
Fair Value	15	11
Certificates of deposit
Marketable Securities [Line Items]
Amortized Cost	9	13
Fair Value	9	13
Municipal debt securities
Marketable Securities [Line Items]
Amortized Cost	1	1
Fair Value	$ 1	$ 1

Marketable Securities - Contrac

Marketable Securities - Contractual Maturities (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Amortized Cost
Due in 1 year or less	$ 58
Due in 1-5 years	38
Total marketable securities	96	$ 99
Fair Value
Due in 1 year or less	58
Due in 1-5 years	38
Total marketable securities	$ 96	$ 99

Debt - Schedule of Long-Term De

Debt - Schedule of Long-Term Debt Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total debt	$ 1,089	$ 1,089
Deferred financing fees	11	11
Long term debt net of unamortized debt issuance costs	$ 1,078	1,078
4.875% senior notes due 2027
Debt Instrument [Line Items]
Debt instrument interest rate	4.875%
Total debt	$ 500	500
5.5% senior notes due 2025
Debt Instrument [Line Items]
Debt instrument interest rate	5.50%
Total debt	$ 350	350
Industrial revenue bonds (due 2028 through 2034)
Debt Instrument [Line Items]
Total debt	$ 239	$ 239

Debt - Senior Notes and Credit

Debt - Senior Notes and Credit Facility (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Issuance and Repurchase of Senior Notes
Loss on extinguishment of debt	$ 0	$ 22,000,000	$ 0	$ 22,000,000
4.875% senior notes due 2027
Issuance and Repurchase of Senior Notes
Debt instrument interest rate	4.875%		4.875%
Senior Notes
Issuance and Repurchase of Senior Notes
Debt issuance costs		7,000,000		7,000,000
Aggregate consideration of debt repurchase amount		536,000,000		536,000,000
Debt premium		20,000,000		20,000,000
Accrued interest		16,000,000		16,000,000
Loss on extinguishment of debt		21,000,000		21,000,000
Senior Notes | 4.875% senior notes due 2027
Issuance and Repurchase of Senior Notes
Face amount of debt		$ 500,000,000		$ 500,000,000
Debt instrument interest rate		4.875%		4.875%
Senior Notes | 7.75% senior notes due 2018
Issuance and Repurchase of Senior Notes
Debt instrument interest rate		7.75%		7.75%
Credit facility | Credit facility
Issuance and Repurchase of Senior Notes
Loss on extinguishment of debt		$ 1,000,000		$ 1,000,000
Credit Facility
Maximum borrowing limit	$ 220,000,000		$ 220,000,000
Borrowing available under credit facility	176,000,000		176,000,000
Outstanding lines of credit	0		0
Amount of letters of credit outstanding	$ 22,000,000		$ 22,000,000

Debt - Fair Value and Accrued I

Debt - Fair Value and Accrued Interest (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
Fair value of debt	$ 1,115	$ 1,134
Accrued interest	$ 12	$ 12

Derivative Instruments - Narrat

Derivative Instruments - Narrative (Details) MMBTU in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018USD ($)MMBTU	Jun. 30, 2017USD ($)	Jun. 30, 2018USD ($)MMBTU	Jun. 30, 2017USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Typical hedging period			5 years
Net liability aggregate fair value	$ 11,000,000		$ 11,000,000
Collateral provided to counterparties related to derivatives	$ 13,000,000		$ 13,000,000
Cash flow hedging | Commodity contracts
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount of commodity instruments (in mmbtu) | MMBTU	48		48
Loss on cash flow hedge ineffectiveness	$ 0	$ 0	$ 0	$ 0
Cash flow hedging | Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Loss on cash flow hedge ineffectiveness	0	$ 0	0	$ 0
Purchases of products and services | Cash flow hedging | Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Notional amounts of foreign exchange forward contracts	$ 119,000,000		$ 119,000,000

Derivative Instruments - Pretax

Derivative Instruments - Pretax Effects of Derivative Instruments on Consolidated Statements of Operations (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Derivatives in Cash Flow Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Other Comprehensive Income on Derivatives (Effective Portion)	$ 2	$ (4)	$ 2	$ (13)
Amount of Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)	(2)	(1)	(2)	(1)
Derivatives in Cash Flow Hedging Relationships | Cash flow hedging | Commodity contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Other Comprehensive Income on Derivatives (Effective Portion)	0	(1)	(3)	(10)
Derivatives in Cash Flow Hedging Relationships | Cash flow hedging | Commodity contracts | Cost of products sold
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)	(2)	(1)	(2)	(1)
Derivatives in Cash Flow Hedging Relationships | Cash flow hedging | Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Other Comprehensive Income on Derivatives (Effective Portion)	2	(3)	5	(3)
Derivatives in Cash Flow Hedging Relationships | Cash flow hedging | Foreign exchange contracts | Cost of products sold
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)	$ 0	$ 0	0	0
Derivatives Not Designated as Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Income on Derivatives			0	(1)
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			$ 0	$ (1)

Derivative Instruments - Locati

Derivative Instruments - Locations on Balance Sheet and Statement of Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Derivative assets	$ 7	$ 2
Derivative liabilities	18	17
Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Derivative assets	0	0
Derivative liabilities	0	0
Derivatives Not Designated as Hedging Instruments | Commodity contracts | Other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	0
Derivatives Not Designated as Hedging Instruments | Commodity contracts | Accrued expenses
Derivatives, Fair Value [Line Items]
Derivative liabilities	0	0
Cash flow hedging | Derivatives in Cash Flow Hedging Relationships
Derivatives, Fair Value [Line Items]
Derivative assets	7	2
Derivative liabilities	18	17
Cash flow hedging | Derivatives in Cash Flow Hedging Relationships | Commodity contracts | Other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	1	1
Cash flow hedging | Derivatives in Cash Flow Hedging Relationships | Commodity contracts | Other assets
Derivatives, Fair Value [Line Items]
Derivative assets	2	1
Cash flow hedging | Derivatives in Cash Flow Hedging Relationships | Commodity contracts | Accrued expenses
Derivatives, Fair Value [Line Items]
Derivative liabilities	6	6
Cash flow hedging | Derivatives in Cash Flow Hedging Relationships | Commodity contracts | Other liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	12	8
Cash flow hedging | Derivatives in Cash Flow Hedging Relationships | Foreign exchange contracts | Other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	2	0
Cash flow hedging | Derivatives in Cash Flow Hedging Relationships | Foreign exchange contracts | Other assets
Derivatives, Fair Value [Line Items]
Derivative assets	2	0
Cash flow hedging | Derivatives in Cash Flow Hedging Relationships | Foreign exchange contracts | Accrued expenses
Derivatives, Fair Value [Line Items]
Derivative liabilities	0	3
Cash flow hedging | Derivatives in Cash Flow Hedging Relationships | Foreign exchange contracts | Other liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ 0	$ 0

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 77	$ 148
Equity mutual funds	6	6
Derivative assets	7	2
Derivative liabilities	(18)	(17)
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	70	68
U.S. government and agency debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	1	6
Asset-backed debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	15	11
Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	9	13
Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	1	1
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	44	124
Equity mutual funds	6	6
Derivative assets	0	0
Derivative liabilities	0	0
Level 1 | Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
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
Level 1 | Asset-backed debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Level 1 | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Level 1 | Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	33	24
Equity mutual funds	0	0
Derivative assets	7	2
Derivative liabilities	(18)	(17)
Level 2 | Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	70	68
Level 2 | U.S. government and agency debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	1	6
Level 2 | Asset-backed debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	15	11
Level 2 | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	9	13
Level 2 | Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	1	1
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
Level 3 | Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
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
Level 3 | Asset-backed debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Level 3 | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Level 3 | Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	$ 0	$ 0

Employee Retirement Plans - Com

Employee Retirement Plans - Components Of Net Pension and Postretirement Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost of benefits earned	$ 12	$ 11	$ 24	$ 21
Interest cost on projected benefit obligation	16	15	32	31
Expected return on plan assets	(24)	(23)	(48)	(46)
Settlement	0	(20)	0	(20)
Net amortization	8	5	16	10
Net pension and postretirement cost	12	28	24	36
Defined Benefit Plan, Plan Assets, Contributions by Employer			50
Postretirement
Defined Benefit Plan Disclosure [Line Items]
Service cost of benefits earned	1	1	2	2
Interest cost on projected benefit obligation	1	1	2	2
Net amortization	(6)	(6)	(12)	(12)
Net pension and postretirement cost	$ (4)	$ (4)	$ (8)	$ (8)

Employee Retirement Plans - Nar

Employee Retirement Plans - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Pension
Defined Benefit Plan Disclosure [Line Items]
Loss due to settlement	$ 0	$ 20	$ 0	$ 20
Contribution by employer			50
Estimated total contributions in current year	$ 60		60
Pension | Canada
Defined Benefit Plan Disclosure [Line Items]
Contribution by employer			2
Supplemental pension plan | United States
Defined Benefit Plan Disclosure [Line Items]
Contribution by employer			$ 1
USG Corporation Pension Plan - L&W Supply | Income from Discontinued Operations | Pension
Defined Benefit Plan Disclosure [Line Items]
Loss due to settlement		13		13
USG Corporation Pension Plan - L&W Supply | Other (expense) income, net | Pension
Defined Benefit Plan Disclosure [Line Items]
Loss due to settlement		$ 7		$ 7

Share-Based Compensation - Awar

Share-Based Compensation - Awards Granted (Details)	6 Months Ended
	Jun. 30, 2018USD ($)$ / sharesshares
MSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares) | shares	428,574
Weighted average fair value (in usd per share) | $ / shares	$ 34.22
Expected volatility	32.62%
Risk-free rate	2.37%
Expected term (in years)	2 years 11 months 12 days
Expected dividends | $	$ 0
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares) | shares	103,819
Weighted average fair value (in usd per share) | $ / shares	$ 34.21
Expected volatility	32.61%
Risk-free rate	2.37%
Expected term (in years)	2 years 11 months 12 days
Expected dividends | $	$ 0
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares) | shares	44,000
Weighted average fair value (in usd per share) | $ / shares	$ 36.92

Share-Based Compensation - Term

Share-Based Compensation - Terms of Awards Granted (Details)	6 Months Ended
	Jun. 30, 2018
MSUs
Share Based Compensation [Abstract]
Vesting period	3 years
Minimum of range for number of shares earned	0.00%
Maximum of range for number of shares earned	150.00%
Performance Shares
Share Based Compensation [Abstract]
Vesting period	3 years
Minimum of range for number of shares earned	0.00%
Maximum of range for number of shares earned	200.00%
RSUs
Share Based Compensation [Abstract]
Maximum of range for number of shares earned	100.00%

Share-Based Compensation - Othe

Share-Based Compensation - Other (Details) - shares shares in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
MSUs, performance shares, RSUs and stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	0	0.7	0	0.9

Supplemental Balance Sheet In59

Supplemental Balance Sheet Information - Inventories (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Finished goods	$ 153	$ 140
Work in progress	39	39
Raw materials	73	73
Total	$ 265	$ 252

Supplemental Balance Sheet In60

Supplemental Balance Sheet Information - Accrued Expenses (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Self-insurance reserves	$ 14	$ 12
Employee compensation	16	17
Interest	12	12
Derivatives	6	9
Pension and other postretirement benefits	17	17
Environmental	13	17
Other	52	51
Total	$ 130	$ 135

Supplemental Balance Sheet In61

Supplemental Balance Sheet Information - Asset Retirement Obligations (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	$ 118	$ 113
Accretion expense	3	3
Liabilities settled	(1)	0
Foreign currency translation	(1)	1
Ending balance	$ 119	$ 117

Supplemental Balance Sheet In62

Supplemental Balance Sheet Information - Asset Dispositions (Details) $ in Millions	3 Months Ended
	Jun. 30, 2018USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Gain on disposition of assets	$ 13
Gain on disposition of assets, net of tax	$ 9

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Treasury Stock (Details) - USD ($) shares in Thousands, $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ (169)
Ending balance	$ (219)
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	(5,571)	0
Repurchase of common stock for tax withholdings related to stock-based compensation (in shares)	(204)	(107)
Repurchase of common stock under share repurchase program (in shares)	(2,156)	(3,161)
Stock issuances (in shares)	918	165
Ending balance (in shares)	(7,013)	(3,103)
Beginning balance	$ (169)	$ 0
Repurchase of common stock for tax withholdings related to stock-based compensation	(7)	(3)
Repurchase of common stock under share repurchase program	(76)	(97)
Stock issuances	33	5
Ending balance	$ (219)	$ (95)

Stockholders' Equity - Accumula

Stockholders' Equity - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ 1,845
Other comprehensive income (loss) before reclassifications, net of tax	(21)	$ 43
Less: Amounts reclassified from AOCI, net of tax	(9)	(13)
Other comprehensive income, net of tax	(12)	56
Ending balance	1,863
Derivatives
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	16	27
Other comprehensive income (loss) before reclassifications, net of tax	2	(8)
Less: Amounts reclassified from AOCI, net of tax	(2)	(1)
Other comprehensive income, net of tax	4	(7)
Ending balance	20	20
Defined Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(297)	(246)
Other comprehensive income (loss) before reclassifications, net of tax	3	3
Less: Amounts reclassified from AOCI, net of tax	(3)	(12)
Other comprehensive income, net of tax	6	15
Ending balance	(291)	(231)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(108)	(166)
Other comprehensive income (loss) before reclassifications, net of tax	(26)	48
Less: Amounts reclassified from AOCI, net of tax	(4)	0
Other comprehensive income, net of tax	(22)	48
Ending balance	(130)	(118)
AOCI Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(389)	(385)
Ending balance	$ (401)	$ (329)

Stockholders' Equity - Amounts

Stockholders' Equity - Amounts Reclassified from AOCI (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net reclassification from AOCI for cash flow hedges included in cost of products sold	$ (696)	$ (643)	$ (1,343)	$ (1,251)
Net reclassification in AOCI for amortization of prior service cost included in other income, net	(3)	(2)	0	4
Net reclassification from AOCI for amortization of prior service cost included in (loss) income from discontinued operations, net of tax	0	(10)	1	(10)
Less: Income tax benefit on reclassification from AOCI included in income tax expense	(13)	(20)	(22)	(49)
Net income	58	36	95	91
Amounts reclassified from AOCI, net of tax | Derivatives
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net reclassification from AOCI for cash flow hedges included in cost of products sold	(2)	(1)	(2)	(1)
Less: Income tax benefit on reclassification from AOCI included in income tax expense	0	0	0	0
Net income	(2)	(1)	(2)	(1)
Amounts reclassified from AOCI, net of tax | Defined Benefit Plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net reclassification in AOCI for amortization of prior service cost included in other income, net	(2)	(7)	(4)	(7)
Net reclassification from AOCI for amortization of prior service cost included in (loss) income from discontinued operations, net of tax	0	(8)	0	(8)
Less: Income tax benefit on reclassification from AOCI included in income tax expense	0	(3)	(1)	(3)
Net income	(2)	(12)	(3)	(12)
Amounts reclassified from AOCI, net of tax | Foreign Currency Translation
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net reclassification from AOCI for amortization of prior service cost included in (loss) income from discontinued operations, net of tax	(6)	0	(6)	0
Less: Income tax benefit on reclassification from AOCI included in income tax expense	(2)	0	(2)	0
Net income	$ (4)	$ 0	$ (4)	$ 0

Stockholders' Equity - Narrativ

Stockholders' Equity - Narrative (Details) $ in Millions	6 Months Ended
	Jun. 30, 2018USD ($)
Equity [Abstract]
Estimated after-tax loss on derivatives to be reclassified from AOCI to earnings within the next 12 months	$ 2

Income Taxes - Schedule of Comp

Income Taxes - Schedule of Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Income tax expense	$ 13	$ 20	$ 22	$ 49
Effective tax rate	18.30%	30.30%	19.00%	32.70%

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Federal net operating loss carryforwards	$ 429
Foreign deferred tax assets	224
Minimum taxable income needed to fully realize the U.S. federal net deferred tax assets	1,588
Deferred tax assets related to state net operating loss and tax credit carryforwards	166
Valuation allowance on deferred tax assets	173	$ 175
Approximate annual NOL utilization had an ownership change occurred	139
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Federal alternative minimum tax credit carryforwards	$ 19

Litigation (Details)

Litigation (Details) $ in Millions	Jun. 30, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2015Homebuilder
Commitments and Contingencies Disclosure [Abstract]
Number of defendants named in class action lawsuits			7
Homebuilders asserting individual claims			12
Accrual for probable and reasonably estimable liability for environmental cleanup | $	$ 13	$ 17

Merger Agreement - Narrative (D

Merger Agreement - Narrative (Details) - Gebr. Knauf KG and World Cup Acquisition Corporation - USD ($) $ / shares in Units, $ in Millions	Jun. 10, 2018	Jun. 30, 2018	Jun. 30, 2018
Business Acquisition [Line Items]
Common stock, par value (dollars per share)	$ 0.10
Conversion price (dollars per share)	43.50
Special cash dividend declared (dollars per share)	$ 0.50
Affirmative vote of shareholders	80.00%
Termination fee, contingency of merger agreement	$ 215
Merger related costs		$ 8	$ 9