| In millions, except per share items | Dec-31-22 | Dec-31-20 | Dec-31-19 | Dec-31-18 | Dec-31-17 | Dec-31-16 | Dec-31-15 | Dec-31-14 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Net income | 339 | -127 | 84 | 283 | -258 | 128 | 142 | 431 |
| Depreciation and amortization | | 208 | 293 | 308 | 321 | 348 | 359 | 384 |
| Asset impairment charges | | | 58 | 7 | 578 | 29 | 77 | |
| Stock-based compensation | | | 9 | 8 | 6 | 7 | 5 | 4 |
| Deferred taxes | | | -16 | 13 | -207 | 9 | -56 | -201 |
| Change in working capital [+] | 121 | 14 | -34 | -16 | 1 | -32 | -63 | -10 |
| Accounts receivable | | | 96 | 18 | -72 | 18 | -22 | 39 |
| Inventories | | | -22 | -28 | 21 | 14 | -84 | -29 |
| Income taxes | 59 | 60 | -43 | -32 | 12 | -18 | 38 | 12 |
| Other | 62 | -46 | -65 | 26 | 40 | -46 | 5 | -32 |
| Other operating activities | 144 | 316 | 48 | -49 | 8 | -24 | -11 | |
| Cash from operations | 604 | 411 | 442 | 554 | 449 | 465 | 453 | 634 |
| |
| Capital expenditures [+] | 440 | 175 | -255 | -195 | -182 | -347 | -289 | -236 |
| Purchases of property and equipment | 440 | 175 | -255 | -195 | -182 | -347 | -289 | -236 |
| Sales of property and equipment | 33 | 3 | 1 | 5 | 19 | 1 | | |
| Acquisitions | | 30 | | | -8 | -46 | | -546 |
| Other cash from investing | -637 | -410 | | -6 | | 1 | 45 | -4 |
| Cash from investing | -164 | -202 | -254 | -196 | -171 | -391 | -244 | -786 |
| |
| Cash dividends paid | | | -110 | -108 | -104 | -102 | -100 | -84 |
| Repurchase of common stock, net | | -59 | -219 | | | -10 | -50 | -38 |
| Other cash from financing | -350 | 94 | 92 | -274 | -170 | 39 | -99 | -204 |
| Cash from financing | -350 | 35 | -237 | -382 | -274 | -73 | -249 | -326 |
| |
| Free cash flow | 1,044 | 586 | 187 | 359 | 267 | 118 | 164 | 398 |
| Per share (diluted) | | $10.58 | $3.05 | $5.69 | $4.26 | $1.88 | $2.59 | $6.13 |
| |
| Cash paid for interest | 116 | 52 | 46 | 57 | 58 | 64 | 133 | 92 |
| Cash paid for income taxes | 25 | -22 | 59 | 71 | 33 | 40 | 34 | 18 |