| In millions, except per share items | Jun-30-23 | Mar-31-23 | Dec-31-22 | Sep-30-22 | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 |
| | 10-Q | 10-Q | 10-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q |
| Net income | -8.4 | -19.2 | -78.9 | -37.0 | -20.2 | -32.6 | -133.6 | 77.9 |
| Depreciation and amortization | 2.4 | 2.4 | 2.6 | 3.4 | 4.2 | 2.8 | 6.5 | 3.8 |
| Asset impairment charges | | | 21.2 | 29.0 | 11.2 | 3.5 | 123.9 | 1.9 |
| Stock-based compensation | 2.3 | 2.6 | 4.5 | 4.3 | 2.6 | 3.7 | 2.4 | 2.7 |
| Change in working capital [+] | -5.4 | -38.6 | 20.3 | 5.3 | 1.0 | -11.9 | 138.0 | 1.9 |
| Accounts receivable | 2.4 | 8.2 | -3.9 | -0.8 | 5.5 | -3.5 | -7.4 | -3.6 |
| Inventories | -0.4 | -6.8 | -3.0 | 3.9 | -4.3 | -3.9 | -2.8 | 3.4 |
| Other current assets | 1.3 | -0.8 | 1.9 | 2.9 | -2.6 | -1.2 | 2.0 | -0.2 |
| Accounts payable | -4.0 | 1.6 | -0.9 | | 0.2 | -0.2 | -1.6 | |
| Other | -4.7 | -40.7 | 26.1 | -0.7 | 2.1 | -3.2 | 147.8 | 2.3 |
| Other operating activities | -2.7 | 5.1 | 5.8 | -18.4 | -16.1 | 0.6 | -173.1 | -119.8 |
| Cash from operations | -11.8 | -47.7 | -24.4 | -13.4 | -17.3 | -33.9 | -35.9 | -31.5 |
| |
| Capital expenditures | -0.5 | -0.8 | -0.4 | -0.9 | -1.5 | -0.7 | -0.5 | -2.3 |
| Purchases of property and equipment | -0.5 | -0.8 | -0.4 | -0.9 | -1.5 | -0.7 | -0.5 | -2.3 |
| Purchases of intangible assets | 0.0 | | -0.4 | -0.8 | -0.4 | 0.0 | -0.1 | -0.2 |
| Purchases of short-term investments, net | -1.1 | -309.3 | 155.9 | -119.1 | -39.3 | | 79.7 | 0.0 |
| Purchases of short-term investments | -57.2 | -422.6 | 4.0 | -118.1 | -157.3 | | 0.2 | 0.4 |
| Sales of short-term investments | 56.1 | 113.4 | 151.9 | -1.1 | 118.0 | | 79.5 | -0.4 |
| Other cash from investing | 6.4 | 6.2 | 3.3 | 0.8 | 0.8 | 0.8 | 2.2 | -1.1 |
| Cash from investing | 4.8 | -303.8 | 158.5 | -120.0 | -40.4 | 0.1 | 81.3 | -3.7 |
| |
| Other cash from financing | 0.0 | -0.7 | -0.6 | -0.2 | -1.6 | -0.5 | -0.3 | -4.3 |
| Cash from financing | 0.0 | -0.7 | -0.6 | -0.2 | -1.6 | -0.5 | -0.3 | -4.3 |
| |
| Free cash flow | -12.3 | -48.5 | -24.7 | -14.3 | -18.8 | -34.6 | -36.4 | -33.8 |
| Per share (diluted) | ($0.03) | ($0.13) | ($0.07) | ($0.04) | ($0.05) | ($0.09) | ($0.10) | ($0.09) |
| |
| Cash paid for income taxes | 0.1 | 32.9 | 0.0 | 0.0 | 0.1 | 0.1 | 0.0 | 0.0 |