| In millions, except per share items | Mar-31-23 | Dec-31-22 | Sep-30-22 | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 | Jun-30-21 |
| | 10-Q | 10-Q | 10-Q | 8-K | 10-Q | 10-Q | 10-Q | 10-K |
| Operating activities: | | | | | | | | |
| Net loss | -12.7 | -32.8 | -6.5 | 77.4 | -34.9 | -24.9 | -17.5 | -10.7 |
| Adjustments to reconcile net loss to net cash provided (used) by operating activities: | | | | | | | | |
| Depreciation and amortization | 3.3 | 3.5 | 3.6 | | 3.7 | 3.8 | 4.1 | 4.2 |
| Goodwill impairment | | 12.3 | | | 18.3 | | | |
| Stock-based compensation expense | 1.4 | 1.7 | 2.1 | | 2.1 | 1.9 | 1.9 | 1.7 |
| Operating lease impairment due to restructuring | | | | | | | | |
| Deferred income tax | | | | | 0.0 | 10.7 | -5.3 | -0.6 |
| Gain on sale of property, plant and equipment | -0.1 | 0.0 | 0.1 | 0.7 | -0.6 | 0.0 | -0.1 | -0.1 |
| Provision for uncollectible accounts | 0.0 | 0.0 | -0.1 | | 0.1 | 0.0 | 0.0 | 0.1 |
| Other | 0.1 | 0.1 | 0.1 | | 0.1 | 0.0 | | 0.1 |
| Changes in operating assets and liabilities increasing (decreasing) cash: | | | | | | | | |
| Accounts receivable | 18.6 | -32.7 | 4.6 | | -16.2 | 23.3 | 3.1 | 8.5 |
| Costs and estimated earnings in excess of billings on uncompleted contracts | -6.8 | 13.0 | -14.9 | 15.6 | -11.9 | -0.7 | -3.0 | 7.2 |
| Inventories | 0.0 | 0.4 | 1.6 | | -0.6 | 0.0 | 1.0 | -1.1 |
| Other assets and liabilities | 15.6 | -1.8 | -3.4 | 2.8 | 1.0 | 2.1 | -5.9 | -4.1 |
| Accounts payable | -14.6 | 11.6 | -6.4 | | 12.1 | -10.0 | 5.1 | 10.6 |
| Billings on uncompleted contracts in excess of costs and estimated earnings | 15.0 | 46.5 | -11.8 | | -11.0 | 33.9 | -2.9 | -4.2 |
| Accrued expenses | 0.2 | -4.1 | -4.2 | 6.7 | 3.9 | -9.5 | -1.1 | -1.4 |
| Net cash provided (used) by operating activities | 20.0 | 17.6 | -35.2 | 22.5 | -33.9 | 30.5 | -19.2 | 10.2 |
| |
| Investing activities: | | | | | | | | |
| Capital expenditures | -3.4 | -1.3 | -1.6 | 1.3 | -0.8 | -0.4 | -0.2 | -0.5 |
| Proceeds from asset sales | 0.1 | 0.0 | 0.0 | | 1.1 | 0.0 | 0.1 | 0.3 |
| Net cash used by investing activities | -3.3 | -1.2 | -1.6 | 0.1 | 0.4 | -0.3 | -0.1 | -0.2 |
| |
| Financing activities: | | | | | | | | |
| Advances under asset-backed credit facility | | 10.0 | | | | | | |
| Repayments of advances under senior secured revolving credit facility | | -10.0 | | | | | | |
| Payment of debt amendment fees | | | | 1.1 | 0.0 | -0.1 | -0.9 | -0.4 |
| Issuances of common stock | 0.1 | 0.1 | 0.1 | | 0.2 | 0.1 | 0.1 | 0.1 |
| Proceeds from issuance of common stock under employee stock purchase plan | 0.1 | 0.1 | 0.1 | | 0.1 | 0.1 | 0.1 | 0.1 |
| Repurchase of common stock for payment of statutory taxes due on equity-based compensation | | | -0.3 | 0.9 | | | -0.9 | |
| Net cash used by financing activities | 0.1 | 0.1 | -0.2 | 1.9 | -0.1 | 0.1 | -1.8 | -0.1 |
| |
| Supplemental disclosure of cash flow information: | | | | | | | | |
| Income taxes | -13.3 | | | 2.8 | -2.5 | -0.3 | | 0.3 |
| Interest, including payment of debt amendment fees | 0.6 | 0.6 | 0.4 | | 0.7 | 0.2 | 1.6 | 0.4 |
| Non-cash investing and financing activities: | | | | | | | | |
| Purchases of property, plant and equipment on account | -0.4 | 0.4 | 0.1 | | 0.1 | 0.0 | 0.1 | 0.1 |