CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Sep. 26, 2021	Dec. 27, 2020
Current assets:
Cash and cash equivalents	$ 369.9	$ 380.8
Restricted cash	0.0	0.7
Accounts receivable, net	85.4	95.3
Unbilled receivables, net	189.3	177.0
Inventoried costs	90.9	81.2
Prepaid expenses	11.7	12.0
Other current assets	25.4	17.8
Total current assets	772.6	764.8
Property, plant and equipment, net	158.8	143.8
Operating lease right-of-use assets	38.8	42.9
Goodwill	483.7	483.9
Intangible assets, net	39.3	43.0
Other assets	84.6	84.4
Total assets	1,577.8	1,562.8
Current liabilities:
Accounts payable	43.6	55.4
Accrued expenses	28.7	34.7
Accrued compensation	51.3	48.1
Accrued interest	6.4	1.5
Billings in excess of costs and earnings on uncompleted contracts	57.7	34.0
Current portion of operating lease liabilities	9.2	8.9
Other current liabilities	10.6	11.9
Current liabilities of discontinued operations	3.1	3.1
Total current liabilities	210.6	197.6
Long-term debt	296.5	301.0
Operating lease liabilities, net of current portion	34.0	38.6
Other long-term liabilities	77.3	83.0
Long-term liabilities of discontinued operations	2.5	2.5
Total liabilities	620.9	622.7
Commitments and contingencies
Redeemable noncontrolling interest	15.1	14.8
Stockholders’ equity:
Preferred stock, $0.001 par value, 5,000,000 shares authorized, 0 shares outstanding at September 26, 2021 and December 27, 2020	0.0	0.0
Common stock, $0.001 par value, 195,000,000 shares authorized; 123,986,345 and 123,047,147 shares issued and outstanding at September 26, 2021 and December 27, 2020, respectively	0.0	0.0
Additional paid-in capital	1,572.3	1,556.3
Accumulated other comprehensive income	1.3	1.4
Accumulated deficit	(631.8)	(632.4)
Total stockholders’ equity	941.8	925.3
Total liabilities and stockholders’ equity	$ 1,577.8	$ 1,562.8