| In millions, except per share items | Dec-31-18 | Dec-31-17 | Dec-31-16 | Dec-31-15 | Dec-31-14 | Dec-31-13 | Dec-31-12 | Dec-31-11 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Operating Activities | | | | | | | | |
| Net income | 196.0 | 88.0 | 510.0 | 991.0 | | | | |
| Less: Income (loss) from discontinued operations, net of tax | 3.0 | -9.0 | 299.0 | 15.0 | 12.0 | -2.0 | 57.0 | 6.0 |
| Less: Gain on sale of discontinued operations, net of tax | | | 279.0 | | | -2.0 | 55.0 | |
| Income from continuing operations | 193.0 | 97.0 | 211.0 | 976.0 | | | | |
| |
| Adjustments to reconcile income from continuing operations to net cash: | | | | | | | | |
| Depreciation, depletion, amortization, and accretion | 150.0 | 132.0 | 134.0 | 131.0 | 142.0 | 155.0 | 156.0 | 164.0 |
| Loss on extinguishment of debt | | 22.0 | 37.0 | 19.0 | | | 41.0 | |
| Long-lived asset impairment charges | | | | | | | | |
| Recovery of receivable | | | | | | | | |
| Share-based compensation expense | 21.0 | 18.0 | 18.0 | 14.0 | 20.0 | 19.0 | 17.0 | 21.0 |
| Deferred income taxes | 28.0 | 255.0 | 57.0 | -742.0 | 4.0 | 2.0 | 4.0 | -8.0 |
| (Gain) loss on asset dispositions | -12.0 | 1.0 | -9.0 | -13.0 | -11.0 | -1.0 | -8.0 | -6.0 |
| Income from equity method investments | -42.0 | -59.0 | -49.0 | -50.0 | -35.0 | -1.0 | | |
| Dividends received from equity method investments | 30.0 | 42.0 | 47.0 | 38.0 | | | | |
| Pension settlement | | | | | | | | |
| (Increase) decrease in working capital | | | | | | | | |
| Receivables | -5.0 | -32.0 | 6.0 | 21.0 | -35.0 | -44.0 | -6.0 | 15.0 |
| Income taxes receivable, net | -4.0 | -12.0 | 3.0 | -3.0 | 3.0 | -1.0 | 6.0 | -5.0 |
| Inventories | -42.0 | -13.0 | -20.0 | -16.0 | -11.0 | -28.0 | -12.0 | -17.0 |
| Other current assets | 1.0 | -3.0 | 9.0 | 1.0 | | -4.0 | 5.0 | -3.0 |
| Payables | 7.0 | 20.0 | 21.0 | -16.0 | 9.0 | -4.0 | 27.0 | 17.0 |
| Accrued expenses | -2.0 | -36.0 | -39.0 | -61.0 | -9.0 | -23.0 | 14.0 | -10.0 |
| Increase in other assets | | 4.0 | | 4.0 | 3.0 | -6.0 | 1.0 | -2.0 |
| Decrease in pension and other postretirement benefits | -40.0 | -57.0 | -142.0 | -28.0 | -55.0 | -63.0 | -16.0 | -23.0 |
| Decrease in other liabilities | -23.0 | -13.0 | -6.0 | -7.0 | -12.0 | -6.0 | -5.0 | 17.0 |
| Other, net | 13.0 | 4.0 | 9.0 | 22.0 | -18.0 | 21.0 | -1.0 | -1.0 |
| Net cash provided by operating activities of continuing operations | 281.0 | 382.0 | 314.0 | 279.0 | 160.0 | 80.0 | 10.0 | 11.0 |
| |
| Net cash provided by operating activities of discontinued operations | 3.0 | | 59.0 | 52.0 | 12.0 | | | |
| Net cash provided by operating activities | 284.0 | 382.0 | 373.0 | 331.0 | 172.0 | 80.0 | 68.0 | -205.0 |
| |
| Investing Activities | | | | | | | | |
| Purchases of marketable securities | -102.0 | -105.0 | -274.0 | -246.0 | -204.0 | -205.0 | -137.0 | -355.0 |
| Sales or maturities of marketable securities | 103.0 | 97.0 | 413.0 | 170.0 | 190.0 | 194.0 | 291.0 | 345.0 |
| Capital expenditures | -219.0 | -168.0 | -83.0 | -87.0 | -125.0 | -124.0 | -70.0 | -54.0 |
| Net proceeds from asset dispositions | 14.0 | 2.0 | 12.0 | 58.0 | 13.0 | 2.0 | 14.0 | 9.0 |
| Acquisition of business, including working capital adjustment | 2.0 | -52.0 | | | | | | |
| Return of capital | | | 1.0 | | | | | |
| Insurance proceeds | | 1.0 | 1.0 | | 3.0 | 2.0 | | 2.0 |
| Net cash (used for) provided by investing activities of continuing operations | -195.0 | -225.0 | 70.0 | -61.0 | -679.0 | -157.0 | -1.0 | -1.0 |
| |
| Net cash provided by investing activities of discontinued operations | | 6.0 | 667.0 | -2.0 | -4.0 | | | |
| Net cash (used for) provided by investing activities | -195.0 | -219.0 | 737.0 | -63.0 | -683.0 | -157.0 | 138.0 | -55.0 |
| |
| Financing Activities | | | | | | | | |
| Issuance of debt | | 500.0 | | 350.0 | 3.0 | 361.0 | 248.0 | |
| Repayment of debt | | -521.0 | -1,131.0 | -386.0 | -63.0 | -4.0 | -283.0 | -6.0 |
| Payment of debt issuance fees | | -8.0 | | -6.0 | -3.0 | -6.0 | -5.0 | |
| Issuance of common stock | 11.0 | 15.0 | 4.0 | 6.0 | 4.0 | 4.0 | 4.0 | |
| Repurchase of common stock | -76.0 | -184.0 | | | -7.0 | -9.0 | -6.0 | -3.0 |
| Repurchases of common stock to satisfy employee tax withholding obligations | -15.0 | -4.0 | -2.0 | -8.0 | | | | |
| Net cash used for financing activities of continuing operations | -150.0 | -202.0 | -1,129.0 | -44.0 | -66.0 | 350.0 | -38.0 | -9.0 |
| |
| Effect of exchange rate changes on cash | -5.0 | 6.0 | -5.0 | | | | | |
| Net decrease in cash and cash equivalents from continuing operations | -69.0 | -39.0 | -750.0 | 375.0 | -1,174.0 | 264.0 | 181.0 | -264.0 |
| Net increase in cash and cash equivalents from discontinued operations | 3.0 | 6.0 | 726.0 | 50.0 | 8.0 | | | |
| Net decrease in cash and cash equivalents | -66.0 | -33.0 | -24.0 | | | | | |
| |
| Supplemental Cash Flow Disclosures: | | | | | | | | |
| Interest paid, net of interest capitalized | 53.0 | 82.0 | 153.0 | 158.0 | 172.0 | 192.0 | 200.0 | 196.0 |
| Income taxes paid, net of refunds received | 9.0 | 10.0 | 4.0 | | 7.0 | 10.0 | 1.0 | 6.0 |
| Noncash Investing and Financing Activities: | | | | | | | | |
| Amount in accounts payable for capital expenditures | 23.0 | 18.0 | 15.0 | 5.0 | 15.0 | 13.0 | 10.0 | 5.0 |
| Reversal of USG Boral Building Products earnout | | | -24.0 | | | | | |