| In millions, except per share items | Dec-31-22 | Dec-31-21 | Dec-31-20 | Dec-31-19 | Dec-31-18 | Dec-31-17 | Dec-31-16 | Dec-31-15 |
| | 10-K | 10-K | 10-K | 10-K/A | 10-K | 10-K | 10-K | 10-K/A |
| Net income | -422.8 | -144.0 | -179.8 | -512.4 | -173.5 | -228.3 | -48.1 | 0.0 |
| Depreciation and amortization | 71.8 | 77.2 | 94.0 | 100.9 | 138.1 | 98.9 | 79.6 | 75.4 |
| Asset impairment charges | 171.2 | | | 349.6 | 48.1 | 69.4 | | |
| Stock-based compensation | 1.0 | 3.9 | 2.8 | 7.8 | 7.6 | 6.7 | 7.1 | 8.1 |
| Deferred taxes | 0.1 | 6.6 | 7.9 | 1.1 | 3.2 | -67.5 | -15.7 | -27.2 |
| Change in working capital [+] | 145.5 | -32.0 | 117.9 | -4.3 | 7.0 | 72.1 | 32.4 | -17.1 |
| Accounts receivable | 77.7 | 17.4 | 54.5 | 4.4 | -19.3 | -4.8 | 20.8 | 11.6 |
| Other current assets | -7.8 | -1.6 | -1.4 | -4.8 | -2.8 | 1.0 | 5.0 | |
| Other | 75.6 | -47.8 | 64.8 | -3.9 | 29.2 | 75.9 | 6.6 | -28.6 |
| Other operating activities | -53.9 | -23.3 | -72.6 | -6.5 | -7.0 | 100.5 | 16.9 | -31.8 |
| Cash from operations | -87.2 | -111.5 | -29.8 | -63.9 | 23.6 | 51.8 | 72.1 | 7.4 |
| |
| Capital expenditures [+] | -22.0 | -16.5 | -15.5 | -20.5 | -27.5 | -22.3 | -20.9 | -13.9 |
| Purchases of property and equipment | -18.3 | -14.6 | -11.7 | -14.4 | -20.1 | -14.4 | -7.9 | -10.7 |
| Capitalized product costs | -3.7 | -2.0 | -3.8 | -6.2 | -7.4 | -7.8 | -13.0 | -3.3 |
| Sales of property and equipment | 0.2 | 7.3 | 50.1 | 0.4 | 3.6 | 4.6 | 0.6 | 0.2 |
| Acquisitions | | | -13.2 | -5.0 | -34.8 | -423.8 | | |
| Other cash from investing | | | | | | 0.1 | -11.3 | -20.7 |
| Cash from investing | -21.8 | -9.3 | 21.4 | -25.2 | -58.8 | -441.4 | -31.6 | -34.4 |
| |
| Issuance of common stock, net | -0.5 | | | -3.5 | -7.2 | 204.2 | | |
| Financing costs | -7.1 | -1.2 | -16.2 | 0.0 | -0.1 | -38.8 | | |
| Other cash from financing | 100.0 | 97.5 | 47.2 | 62.6 | 4.5 | 193.5 | -43.3 | 21.6 |
| Cash from financing | 106.6 | 98.7 | 63.4 | 59.1 | -2.6 | 436.4 | -43.3 | 21.6 |
| |
| Free cash flow | -105.5 | -126.1 | -41.4 | -78.2 | 3.5 | 37.3 | 64.2 | -3.2 |
| Per share (diluted) | ($1.77) | ($21.71) | ($18.42) | ($1.74) | ($0.08) | $0.28 | $0.80 | ($101.48) |
| |
| Cash paid for interest | 98.6 | 188.8 | 152.7 | 144.5 | 146.1 | 69.6 | 96.2 | 87.3 |
| Cash paid for income taxes | 5.8 | 3.8 | 2.7 | 7.9 | 7.8 | 5.7 | 3.8 | 1.8 |