| 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 | 10-K | 10-K | 10-K | 10-K |
| Net income | 141.6 | -64.1 | 854.0 | -23.8 | -77.2 | -117.0 | -630.2 | -171.8 |
| Depreciation and amortization | 102.0 | 108.0 | 105.2 | 105.3 | 95.7 | 87.9 | 96.9 | 47.2 |
| Asset impairment charges | | | 75.6 | | | | 599.1 | 211.5 |
| Stock-based compensation | 196.3 | 197.3 | 189.7 | 159.9 | 148.8 | 140.3 | 134.6 | 111.5 |
| Deferred taxes | -52.1 | -15.6 | -890.0 | -82.8 | -68.4 | 44.5 | -228.1 | -76.8 |
| Change in working capital [+] | -76.5 | 72.6 | -195.9 | -92.2 | -48.5 | -56.4 | -151.1 | 49.5 |
| Accounts receivable | -82.0 | 65.6 | -59.0 | -37.9 | -54.3 | -25.3 | -51.5 | -16.4 |
| Inventories | -68.3 | -35.1 | -61.2 | -107.6 | -23.7 | -96.9 | -64.5 | -51.0 |
| Other current assets | 7.8 | 29.8 | 18.3 | -27.0 | -17.8 | -20.7 | 19.3 | 25.8 |
| Other | 66.0 | 12.4 | -94.1 | 80.2 | 47.3 | 86.4 | -54.5 | 91.0 |
| Other operating activities | -135.3 | 6.3 | -53.2 | -18.1 | -30.2 | -107.9 | -49.1 | -390.6 |
| Cash from operations | 175.9 | 304.5 | 85.4 | 48.3 | 20.2 | -8.8 | -227.8 | -219.5 |
| |
| Capital expenditures | -121.0 | -95.6 | -114.3 | -145.0 | -144.6 | -199.2 | -148.4 | -227.7 |
| Purchases of property and equipment | -121.0 | -95.6 | -114.3 | -145.0 | -144.6 | -199.2 | -148.4 | -227.7 |
| Purchases of intangible assets | -10.6 | -23.6 | -23.2 | -18.4 | | | | |
| Acquisitions | | | | | | | -2.8 | -538.4 |
| Purchases of short-term investments, net | | | | -632.0 | -634.8 | -655.4 | -699.7 | -448.5 |
| Purchases of short-term investments | | | | -632.0 | -634.8 | -655.4 | -699.7 | -873.2 |
| Sales of short-term investments | | | | | | | | 424.7 |
| Other cash from investing | 111.5 | -247.1 | 83.9 | 764.4 | 1,043.7 | 549.2 | 366.9 | 34.9 |
| Cash from investing | -20.0 | -366.3 | -53.6 | -31.0 | 264.4 | -305.5 | -484.0 | -1,179.6 |
| |
| Issuance of common stock, net | | | -50.0 | | | | 712.9 | 888.3 |
| Option exercises | 69.3 | 49.2 | 71.9 | 31.6 | 67.5 | 60.9 | 74.2 | 63.0 |
| Other cash from financing | 50.7 | 49.1 | 303.0 | -43.1 | -320.5 | 568.0 | 88.4 | 100.5 |
| Cash from financing | -18.7 | 0.0 | 181.1 | -74.7 | -388.0 | 507.1 | 727.1 | 925.7 |
| |
| Free cash flow | 54.9 | 209.0 | -28.9 | -96.8 | -124.4 | -208.0 | -376.2 | -447.2 |
| Per share (diluted) | $0.29 | $1.14 | ($0.15) | ($0.54) | ($0.70) | ($1.19) | ($2.26) | ($2.79) |
| |
| Cash paid for interest | 10.3 | 10.4 | 12.2 | 8.6 | 11.6 | 8.5 | 8.6 | 9.3 |