| In millions, except per share items | Dec-31-15 | Dec-31-14 | Dec-31-13 | Dec-31-12 | Dec-31-11 | Dec-31-10 | Dec-31-09 | Dec-31-08 |
| | 10-K | 10-K | 10-K | 10-K | 10-K/A | 10-K | 10-K | 10-K |
| Cash flows from operating activities: | | | | | | | | |
| Net loss | -22.8 | -10.6 | -10.2 | -6.1 | -10.4 | -1.5 | -2.9 | |
| Adjustments to reconcile net loss to net cash from operating activities: | | | | | | | | |
| Depreciation of property and equipment | 10.4 | 7.7 | 6.1 | 5.0 | 3.5 | 3.0 | 2.9 | |
| Amortization of software development costs | 6.6 | 5.8 | 5.0 | 4.1 | 3.0 | 1.9 | 1.1 | |
| Amortization of intangible assets | 5.0 | 3.7 | 0.4 | 0.2 | 0.5 | 0.6 | 1.0 | |
| Amortization of deferred debt issuance costs | 0.5 | 0.0 | 0.0 | | | | | |
| Stock-based compensation | 8.8 | 7.1 | 4.3 | 2.0 | 1.4 | 1.3 | 1.4 | |
| Loss on disposal of property and equipment | 0.1 | 0.7 | 0.7 | 0.3 | 0.1 | | | |
| Interest accretion | 2.8 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | | |
| Amortization of investment premium | 0.5 | | | | | | | |
| Deferred income taxes | -0.6 | -9.4 | | | | | | |
| Changes in operating assets and liabilities, net of business acquisitions: | | | | | | | | |
| Accounts and other receivables, net | -9.1 | -8.7 | -3.4 | -5.2 | -3.5 | -0.1 | -1.0 | |
| Other current assets | -2.2 | -1.3 | -1.1 | -0.8 | -0.4 | -0.5 | -0.5 | |
| Other non-current assets | -0.3 | -0.5 | -0.5 | -0.1 | -0.4 | 0.1 | 0.0 | |
| Trade accounts payable | 0.6 | 1.2 | 1.2 | 0.1 | 0.0 | 1.0 | -0.8 | |
| Accrued liabilities | -0.2 | 3.2 | 1.8 | 2.7 | 1.6 | -0.4 | 0.5 | |
| Accrued commissions | 1.2 | 0.6 | 0.5 | | | | | |
| Deferred rent and lease incentive obligation | | | | 0.1 | -0.1 | 0.0 | -0.1 | |
| Other long-term liabilities | -0.2 | -0.2 | 0.3 | | | | | |
| Deferred revenue | 3.4 | 5.9 | 2.5 | 1.9 | 1.1 | -0.3 | -0.1 | |
| Net cash provided by operating activities | 4.9 | 5.2 | 7.6 | 4.4 | -3.2 | 5.1 | 2.2 | |
| |
| Cash flows from investing activities: | | | | | | | | |
| Decrease in restricted cash | | | | 0.2 | | | -0.2 | |
| Sales and maturities of available for sale investments | 37.4 | | | | | 0.1 | 0.2 | |
| Purchases of available for sale investments | -113.0 | | | | | | | |
| Capitalized software development costs | -10.1 | -11.0 | -6.2 | -5.5 | -4.8 | -3.4 | -3.6 | -1.8 |
| Purchases of property and equipment | -14.5 | -13.3 | -5.4 | -3.7 | -5.2 | -1.7 | -1.0 | |
| Business acquisitions, net of cash acquired | | -13.1 | -2.7 | | | | | |
| Net cash used in investing activities | -100.2 | -37.4 | -17.0 | -9.2 | -10.0 | -5.5 | -5.5 | |
| |
| Cash flows from financing activities: | | | | | | | | |
| Proceeds from exercise of options | 3.2 | 2.3 | 7.1 | 3.3 | 1.2 | 1.8 | 0.5 | |
| Proceeds from sale of stock under employee stock purchase plan | 1.6 | 0.8 | 0.4 | 0.3 | 0.2 | 0.1 | 0.5 | |
| Principal payments under debt and capital lease obligations | -11.8 | -4.1 | -3.5 | -3.2 | -2.2 | -1.9 | -1.4 | |
| Purchase of treasury stock | -1.1 | -0.6 | -0.3 | | | | | |
| Payments under revolving credit agreement | -11.0 | -10.0 | -1.0 | -8.5 | -17.5 | -20.5 | -9.2 | |
| Proceeds from issuance of convertible notes, net | 111.2 | | | | | | | |
| Net cash provided by financing activities | 92.0 | 15.4 | 9.8 | 35.9 | 20.7 | -0.1 | 10.1 | |
| |
| Net (decrease) increase in cash and cash equivalents | -3.4 | -16.7 | 0.3 | 31.1 | 7.4 | -0.5 | 6.8 | |
| Cash and cash equivalents at the beginning of the period | 32.4 | 49.1 | 48.8 | 17.7 | 10.3 | 10.9 | 4.1 | |
| Cash and cash equivalents at the end of the period | 29.1 | 32.4 | 49.1 | 48.8 | 17.7 | 10.3 | 10.9 | |
| |
| Supplemental schedule of non-cash investing and financing activities: | | | | | | | | |
| Payments due for property and equipment included in trade accounts payable | 0.4 | 0.4 | 1.2 | 0.1 | 0.2 | 0.1 | 0.0 | |