| In millions, except per share items | Dec-31-21 | Dec-31-20 | Dec-31-19 | Dec-31-18 | Dec-31-17 | Dec-31-16 | Nov-30-15 | Nov-30-14 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K/A | 10-K/A |
| Net income | 143.7 | 137.7 | 141.0 | 137.3 | -9.2 | 18.0 | -16.2 | -50.0 |
| Depreciation and amortization | 61.4 | 65.3 | 74.5 | 72.3 | 72.6 | 64.9 | 65.1 | 63.7 |
| Stock-based compensation | 20.7 | 31.4 | 27.3 | 20.5 | 22.0 | 12.9 | 8.6 | 5.7 |
| Tax benefit from stock-based compensation | | | | | | | | -1.3 |
| Deferred taxes | -18.0 | 37.9 | -5.7 | 4.7 | 125.7 | 4.8 | -27.6 | -7.1 |
| Change in working capital [+] | 63.4 | -15.6 | 1.7 | -15.9 | 21.4 | 55.9 | -56.8 | -13.9 |
| Accounts receivable | 15.0 | 36.9 | 28.8 | -47.3 | 5.6 | 57.9 | -1.0 | 28.9 |
| Inventories | | | | | | | -19.5 | -32.0 |
| Other current assets | 28.8 | 9.2 | -27.9 | 21.5 | 8.9 | -22.9 | -25.7 | -10.8 |
| Accounts payable | 24.3 | -36.8 | 20.3 | -39.4 | 1.6 | 27.0 | -5.1 | -18.2 |
| Income taxes | | | | 0.8 | -0.1 | -0.4 | | 3.7 |
| Other | -4.7 | -24.9 | -19.5 | 48.5 | 5.4 | -5.7 | -5.5 | 14.5 |
| Other operating activities | -71.6 | 107.1 | 22.4 | 33.8 | -19.7 | 2.2 | 94.5 | 155.6 |
| Cash from operations | 199.6 | 363.8 | 261.2 | 252.7 | 212.8 | 158.7 | 67.6 | 152.7 |
| |
| Capital expenditures | -37.3 | -54.6 | -42.9 | -43.2 | -29.4 | -47.6 | -36.8 | -43.4 |
| Purchases of property and equipment | -37.3 | -54.6 | -42.9 | -43.2 | -29.4 | -47.6 | -36.8 | -43.4 |
| Acquisitions | | | | | -17.0 | | | |
| Purchases of short-term investments, net | -1.9 | -6.7 | | 20.4 | -20.0 | | | |
| Purchases of short-term investments | -1.9 | -31.7 | | -47.7 | -24.0 | | | |
| Sales of short-term investments | | 25.0 | | 68.1 | 4.0 | | | |
| Other cash from investing | | 0.3 | 1.1 | 1.9 | | 0.5 | 1.0 | |
| Cash from investing | -39.2 | -61.0 | -41.8 | -20.9 | -66.4 | -47.1 | -35.8 | -35.7 |
| |
| Cash dividends paid | -428.8 | | | | | | | |
| Repurchase of common stock, net | 7.7 | -44.2 | 5.2 | 5.4 | 4.5 | 0.3 | -5.4 | -64.5 |
| Financing costs | | | | -3.3 | | -9.5 | | -4.2 |
| Other cash from financing | -188.4 | -41.7 | -29.3 | -35.2 | -26.2 | 80.4 | -81.2 | 13.7 |
| Cash from financing | -609.5 | -85.9 | -24.1 | -26.5 | -21.7 | 90.2 | -86.6 | -46.6 |
| |
| Free cash flow | 162.3 | 309.2 | 218.3 | 209.5 | 183.4 | 111.1 | 30.8 | 109.3 |
| Per share (diluted) | $1.99 | $3.78 | $2.67 | $2.73 | $2.51 | $1.69 | $0.50 | $1.89 |
| |
| Cash paid for interest | 14.0 | 19.7 | 26.3 | 25.3 | 22.2 | 39.0 | 49.3 | 46.9 |