| In millions, except per share items | Dec-31-19 | Dec-31-18 | Dec-31-17 | Dec-31-16 | Dec-31-15 | Dec-31-14 | Dec-31-13 | Dec-31-12 |
| | 10-K | 10-K | 10-K | 10-K | 10-K/A | 10-K | 10-K | 10-K |
| Cash flows from operating activities: | | | | | | | | |
| Net income (loss) | -13.7 | 4.6 | 3.2 | 0.9 | -3.2 | -7.5 | -0.2 | 5.4 |
| Adjustments to reconcile net loss to net cash provided by operating activities: | | | | | | | | |
| Impairment charges | 10.1 | | | | | | | |
| Depreciation and amortization | 13.4 | 10.8 | 8.2 | 6.9 | 7.8 | 9.7 | 13.2 | 14.3 |
| Amortization of deferred loan costs | 0.1 | 0.1 | 0.1 | 0.1 | 0.0 | 0.1 | 0.2 | 0.2 |
| Noncash interest expense | 0.3 | 1.0 | 1.2 | | | | | |
| Stock-based compensation expense | 4.9 | 5.1 | 7.1 | 5.1 | 3.9 | 4.5 | 6.3 | 6.3 |
| Deferred income taxes | -0.4 | -1.3 | 0.7 | -0.9 | -1.1 | 1.6 | 0.0 | -0.8 |
| Changes in operating assets and liabilities | | | | | | | | |
| Billed receivables | 5.7 | -8.6 | -3.9 | -3.3 | 4.3 | -6.4 | 4.2 | -1.6 |
| Unbilled receivables | -1.6 | -1.0 | -0.5 | | | | | |
| Prepaid expenses and other current assets | -2.6 | 2.4 | -0.4 | -1.5 | 0.7 | 1.6 | -1.3 | 0.7 |
| Operating lease liabilities | -4.5 | -0.2 | -0.1 | | | | | |
| Other assets | | | | -0.1 | | 0.0 | 0.0 | -0.2 |
| Accounts payable and accrued expenses | -3.4 | -2.5 | 1.8 | 3.8 | -5.5 | -2.9 | -9.2 | -2.4 |
| Accrued payroll and related expenses | -2.1 | 0.8 | 1.0 | 2.6 | -3.6 | 0.5 | -5.7 | -1.3 |
| Refund liabilities | -2.1 | -2.1 | 0.1 | 0.1 | 2.4 | -1.3 | -0.6 | 0.4 |
| Deferred revenue | | | | | -0.8 | 0.7 | -0.1 | -0.2 |
| Net cash provided by operating activities | 10.5 | 2.4 | 13.5 | 10.1 | 13.5 | 10.0 | 18.4 | 18.8 |
| |
| Cash flows from investing activities: | | | | | | | | |
| Purchases of property, equipment and software, net of disposal proceeds | -15.0 | -10.4 | -9.4 | -5.9 | -4.5 | -4.7 | -6.9 | -7.9 |
| Net cash used in investing activities | -15.0 | -10.4 | -19.5 | -9.6 | -4.2 | -3.6 | -6.9 | -9.5 |
| |
| Cash flows from financing activities: | | | | | | | | |
| Proceeds from credit facility | 26.4 | 21.5 | 10.0 | 3.6 | | | | |
| Payment of deferred loan costs | -0.5 | 0.0 | -0.2 | | -0.1 | -0.1 | | |
| Payment of earnout liability related to business acquisitions | -4.2 | -4.0 | | | | | | |
| Repurchases of common stock | -4.7 | -4.1 | | -3.8 | -18.1 | -22.7 | | |
| Proceeds from option exercises | 0.2 | 4.4 | 1.2 | 0.3 | 0.1 | 2.8 | 0.9 | 0.6 |
| Net cash (used in) provided by financing activities | 5.5 | 3.0 | 11.0 | -0.1 | -18.4 | -22.7 | -4.6 | 7.8 |
| Effect of exchange rates on cash and cash equivalents | 0.1 | 0.1 | -1.9 | | | | | |
| |
| Supplemental disclosure of cash flow information: | | | | | | | | |
| Cash paid during the period for interest | 1.1 | 0.7 | 0.4 | 0.1 | 0.1 | 0.1 | 0.6 | 0.3 |
| Cash paid during the period for income taxes, net of refunds received | 2.4 | 3.3 | 2.9 | 1.4 | 1.1 | 3.9 | 3.2 | 2.7 |