| In millions, except per share items | Mar-31-16 | Dec-31-15 | Sep-30-15 | Jun-30-15 | Mar-31-15 | Dec-31-14 | Sep-30-14 | Jun-30-14 |
| | 10-Q | 10-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q | 10-Q |
| Assets | | | | | | | | |
| Current assets: | | | | | | | | |
| Cash and cash equivalents | 82.3 | 78.7 | 73.2 | 68.0 | 67.5 | 66.8 | 66.0 | 67.9 |
| Accounts receivable, net of allowance of $243 and $193 at March 31, 2016 and December 31, 2015, respectively | 5.8 | 6.4 | 10.0 | 9.5 | 7.6 | 8.3 | 7.1 | 7.1 |
| Prepaid expenses and other current assets | 1.3 | 1.2 | 0.9 | 1.3 | 1.1 | 1.2 | 1.7 | 2.6 |
| Total current assets | 89.4 | 86.3 | 84.1 | 78.8 | 76.2 | 76.2 | 74.8 | 77.6 |
| Property and equipment, net | 34.0 | 34.2 | 34.5 | 32.2 | 28.6 | 26.1 | 24.5 | 23.3 |
| Restricted cash | 2.8 | 2.8 | 2.2 | 2.2 | 2.2 | 1.8 | 1.8 | 0.5 |
| Goodwill | 52.8 | 52.8 | 52.8 | 52.8 | 52.8 | 52.8 | 52.8 | 52.8 |
| Intangible assets, net | 7.2 | 8.0 | 9.0 | 10.0 | 11.1 | 12.1 | 13.3 | 14.5 |
| Other assets | 0.2 | 0.2 | 0.3 | 1.3 | 0.3 | 0.2 | 0.2 | 1.1 |
| Total assets | 186.4 | 184.3 | 183.0 | 177.3 | 171.2 | 169.3 | 167.5 | 170.0 |
| |
| Liabilities and Stockholders’ Equity | | | | | | | | |
| Liabilities | | | | | | | | |
| Current liabilities: | | | | | | | | |
| Accounts payable | 2.0 | 2.7 | 2.3 | 1.9 | 2.0 | 1.7 | 1.6 | 2.0 |
| Accrued expenses | 9.9 | 22.8 | 9.9 | 10.5 | 9.3 | 19.7 | 9.8 | 8.3 |
| Deferred revenue, short-term | 42.8 | 40.1 | 39.6 | 37.1 | 33.8 | 31.9 | 30.2 | 27.9 |
| Total current liabilities | 54.7 | 54.2 | 51.9 | 49.5 | 45.3 | 43.9 | 42.3 | 38.9 |
| Deferred revenue, long-term | 3.4 | 3.7 | 5.5 | 4.4 | 4.1 | 3.7 | 3.4 | 3.3 |
| Other long-term liabilities | 2.2 | 2.0 | 1.3 | 1.2 | 1.1 | 1.0 | 0.8 | 2.5 |
| Total liabilities | 60.3 | 59.9 | 58.7 | 55.1 | 50.5 | 48.6 | 46.7 | 44.9 |
| |
| Stockholders’ equity: | | | | | | | | |
| Common stock | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| Additional paid in capital | 364.6 | 361.4 | 352.6 | 348.0 | 343.4 | 340.3 | 336.3 | 333.0 |
| Treasury stock, at cost; 670 and 671 shares at March 31, 2016 and December 31, 2015, respectively | -10.3 | -10.3 | -10.0 | -10.0 | -9.9 | -9.9 | -9.9 | -9.9 |
| Accumulated other comprehensive loss | -0.7 | -0.7 | -0.5 | -0.4 | -0.4 | -0.3 | -0.1 | 0.0 |
| Accumulated deficit | -227.6 | -226.0 | -217.8 | -215.3 | -212.5 | -209.4 | -205.5 | -198.0 |
| Total stockholders’ equity | 126.1 | 124.4 | | | | 120.7 | 120.8 | 125.1 |
| Total liabilities and stockholders’ equity | 186.4 | 184.3 | 183.0 | 177.3 | 171.2 | 169.3 | 167.5 | 170.0 |