| In millions, except per share items | Jun-30-23 | Dec-31-22 | Sep-30-22 | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 | Jun-30-21 |
| | 10-Q | 10-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q | 10-Q |
| Net income | | 33.3 | 34.4 | 34.0 | 31.9 | 28.8 | 23.5 | 18.9 |
| Depreciation and amortization | | 1.4 | 1.3 | 1.3 | 1.4 | 1.3 | 1.3 | 1.3 |
| Stock-based compensation | | 1.2 | 1.0 | 0.9 | 0.6 | 0.6 | 0.5 | 0.6 |
| Deferred taxes | | 1.1 | -4.7 | -3.0 | -2.3 | -2.3 | -0.9 | -1.8 |
| Change in working capital | | 28.6 | -53.2 | 57.0 | 25.7 | 2.9 | 44.7 | -53.9 |
| Other | | 28.6 | -53.2 | 57.0 | 25.7 | 2.9 | 44.7 | -53.9 |
| Other operating activities | | 18.2 | 125.8 | -55.2 | -77.8 | -59.6 | -100.0 | 3.4 |
| Cash from operations | | 83.7 | 104.7 | 35.1 | -20.5 | -28.3 | -30.8 | -31.5 |
| |
| Capital expenditures | | -1.4 | -1.5 | -1.5 | -1.5 | -1.1 | -0.8 | -0.7 |
| Purchases of property and equipment | | -1.4 | -1.5 | -1.5 | -1.5 | -1.1 | -0.8 | -0.7 |
| Purchases of short-term investments, net | | -83.6 | -109.6 | -79.7 | -70.4 | -62.4 | -11.4 | -38.4 |
| Purchases of short-term investments | | -115.8 | -144.6 | -116.1 | -107.4 | -98.4 | | -74.5 |
| Sales of short-term investments | | 32.2 | 35.0 | 36.4 | 37.0 | 35.9 | 36.9 | 36.1 |
| Other cash from investing | | -376.7 | -398.4 | -251.2 | -280.7 | -222.5 | -167.0 | -210.3 |
| Cash from investing | | -461.8 | -509.6 | -332.4 | -352.6 | -286.0 | -179.1 | -249.4 |
| |
| Cash dividends paid | | -6.7 | -6.4 | -6.1 | -5.6 | -5.1 | -4.7 | -4.2 |
| Option exercises | | 0.6 | 0.1 | | | | | 0.2 |
| Other cash from financing | | 352.8 | 330.5 | 307.4 | 381.3 | 328.7 | 316.1 | 303.2 |
| Cash from financing | | 345.6 | 324.0 | 301.4 | 375.6 | 323.5 | 310.3 | 297.4 |
| |
| Free cash flow | | 82.3 | 103.1 | 33.5 | -22.0 | -29.4 | -31.6 | -32.2 |
| Per share (diluted) | | $5.40 | $6.77 | $2.20 | ($1.45) | ($1.94) | ($2.09) | ($2.12) |
| |
| Cash paid for interest | | 9.1 | 6.6 | 3.2 | 3.0 | 3.6 | 4.4 | 5.8 |