| In millions, except per share items | Dec-31-14 | Dec-31-13 | Dec-31-12 | Dec-31-11 | Dec-31-10 | Dec-31-09 | Dec-31-08 | Dec-31-07 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Net income | 317.3 | 262.2 | 116.7 | 91.8 | 64.7 | 46.1 | 15.1 | 13.1 |
| Depreciation and amortization [+] | 276.7 | 245.4 | 150.4 | 25.9 | 16.3 | 17.7 | 25.3 | 5.6 |
| Depreciation | 63.5 | 42.2 | 20.2 | 9.5 | 8.4 | 8.0 | 16.0 | 4.0 |
| Amortization of intangible assets | 213.2 | 203.2 | 130.1 | 16.4 | 7.9 | 9.7 | 9.4 | 1.6 |
| Stock-based compensation | 33.6 | 25.6 | 17.7 | 9.4 | 5.9 | 3.7 | 4.1 | 3.0 |
| Tax benefit from stock-based compensation | -3.5 | -9.7 | -19.4 | -10.8 | -13.1 | -4.5 | | |
| Deferred taxes | -58.0 | -44.3 | -37.9 | -5.9 | 3.3 | -0.3 | 0.3 | -1.0 |
| Change in working capital [+] | 97.2 | 29.6 | 46.4 | 16.3 | 39.8 | 5.8 | 15.9 | 0.8 |
| Restricted cash | | | | 1.8 | 0.4 | -1.7 | | |
| Accounts receivable | -294.7 | -217.5 | -134.3 | -110.5 | -9.5 | -16.7 | 8.0 | -3.7 |
| Inventories | | | | | | -0.4 | -0.1 | 0.0 |
| Other current assets | -44.6 | -25.3 | 82.8 | 10.2 | 10.2 | 0.0 | | |
| Accounts payable | 150.0 | 149.4 | 70.6 | 94.8 | 25.1 | 1.6 | 1.7 | 0.7 |
| Accrued expenses | 72.6 | -43.7 | 1.7 | | | | | |
| Other | 213.9 | 166.6 | 25.5 | 20.1 | 13.6 | 23.0 | 6.3 | |
| Other operating activities | -73.0 | -33.3 | -24.0 | -32.1 | -20.7 | 17.8 | -19.1 | 0.6 |
| Cash from operations | 590.2 | 475.4 | 249.7 | 94.7 | 96.3 | 86.4 | 41.6 | 22.1 |
| |
| Capital expenditures | -78.1 | -128.8 | -40.2 | -9.7 | -9.1 | -9.0 | -8.4 | -7.7 |
| Purchases of property and equipment | -78.1 | -128.8 | -40.2 | -9.7 | -9.1 | -9.0 | -8.4 | -7.7 |
| Acquisitions | -2.0 | -388.9 | -1,565.7 | -79.8 | -99.2 | -2.2 | -104.8 | |
| Purchases of short-term investments, net | | | | | 4.6 | -4.6 | | |
| Purchases of short-term investments | | | | | -2.2 | -5.1 | | |
| Sales of short-term investments | | | | | 6.8 | 0.4 | | |
| Other cash from investing | 20.0 | 20.0 | | | | | 0.4 | 0.4 |
| Cash from investing | -60.1 | -497.7 | -1,605.9 | -89.5 | -103.7 | -15.8 | -112.8 | -7.3 |
| |
| Issuance of common stock, net | | | 519.1 | | | 203.1 | | |
| Option exercises | 5.6 | 3.0 | 7.8 | 5.7 | 11.0 | 6.3 | | |
| Financing costs | -2.0 | -2.3 | -18.8 | -1.6 | | | | |
| Other cash from financing | 98.3 | 39.5 | 855.5 | 19.1 | 35.2 | -30.6 | 48.2 | |
| Cash from financing | 94.6 | 38.8 | 1,385.6 | 14.9 | 24.1 | 166.2 | 48.2 | 4.9 |
| |
| Free cash flow | 512.1 | 346.6 | 209.5 | 85.0 | 87.2 | 77.4 | 33.2 | 14.5 |
| Per share (diluted) | $2.46 | $1.68 | $1.25 | $0.67 | $0.69 | $1.44 | $0.70 | $0.67 |