| In millions, except per share items | Mar-31-18 | Dec-31-17 | Sep-30-17 | Jun-30-17 | Mar-31-17 | Dec-31-16 | Sep-30-16 | Jun-30-16 |
| | 10-Q | 10-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q | 10-Q |
| Net income | -130.9 | -301.1 | -49.4 | -20.4 | -98.4 | -279.6 | -179.3 | -2.7 |
| Depreciation and amortization | 18.0 | 24.1 | 31.4 | 28.2 | 25.8 | 25.2 | 26.7 | 20.7 |
| Asset impairment charges | | 310.2 | 62.0 | | 45.4 | 253.7 | 287.9 | |
| Stock-based compensation | 4.8 | 6.6 | 6.5 | 6.2 | 7.0 | 8.8 | 7.7 | 8.4 |
| Change in working capital [+] | 18.0 | 84.1 | -40.7 | 2.0 | 20.7 | 111.7 | 2.5 | -75.2 |
| Accounts receivable | 14.8 | -0.1 | -22.3 | -8.1 | 43.0 | -10.0 | -2.1 | -23.0 |
| Inventories | 2.5 | 2.9 | 26.9 | -4.0 | -19.2 | -9.8 | -11.5 | -11.0 |
| Other current assets | -8.5 | -22.7 | -29.9 | -6.4 | -6.5 | 42.1 | -37.5 | -3.6 |
| Other | 9.3 | 104.1 | -15.5 | 20.4 | 3.3 | 89.5 | 53.6 | -37.6 |
| Other operating activities | 4.6 | -86.4 | -21.2 | | 39.5 | -140.2 | -70.0 | |
| Cash from operations | -85.5 | 37.4 | -11.4 | 18.4 | 39.8 | -20.2 | 75.5 | -50.3 |
| |
| Capital expenditures [+] | -4.0 | -2.6 | -5.2 | -10.3 | -8.7 | -17.5 | -11.3 | -9.6 |
| Purchases of property and equipment | -4.0 | -2.6 | -5.2 | -10.3 | -8.7 | -17.5 | -11.3 | -9.6 |
| Sales of property and equipment | 17.8 | 12.4 | 8.8 | 0.4 | | 0.0 | | 1.3 |
| Purchases of intangible assets | | -0.1 | | | | | | |
| Acquisitions | | -0.1 | | | | | -585.8 | |
| Other cash from investing | | -16.6 | | 11.9 | 0.5 | -4.8 | | 15.0 |
| Cash from investing | 13.8 | -7.0 | 3.6 | 1.9 | -8.2 | -22.3 | -597.1 | 6.7 |
| |
| Option exercises | 0.5 | 0.5 | 0.3 | 0.4 | 0.2 | 0.1 | 0.0 | 1.5 |
| Financing costs | | | | | -0.8 | | -11.9 | |
| Other cash from financing | -5.0 | -5.5 | -5.3 | -5.6 | -56.7 | -8.9 | 374.7 | -0.2 |
| Cash from financing | -5.5 | -6.0 | -5.5 | -6.0 | -56.1 | -9.0 | 386.6 | -1.7 |
| |
| Free cash flow | -89.4 | 34.8 | -16.6 | 8.1 | 31.1 | -37.7 | 64.1 | -59.9 |
| Per share (diluted) | ($1.24) | $0.48 | ($0.23) | $0.11 | $0.43 | ($0.53) | $0.90 | ($0.84) |
| |
| Cash paid for interest | 4.4 | 10.4 | 4.2 | 9.9 | 3.9 | 9.9 | 2.2 | 6.0 |
| Cash paid for income taxes | 2.3 | -0.6 | -0.8 | 0.8 | 3.5 | -0.1 | 0.7 | 20.0 |