CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	6 Months Ended
	Jun. 29, 2025	Jun. 30, 2024
Operating activities:
Net income	$ 7.4	$ 9.2
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization	22.2	19.7
Deferred income taxes	0.0	0.1
Amortization of lease right-of-use assets	6.0	6.0
Stock-based compensation	17.3	15.8
Amortization of deferred financing costs	0.3	0.3
Changes in assets and liabilities, net of acquisitions:
Accounts receivable	(23.1)	(3.0)
Unbilled receivables	(49.9)	(6.4)
Inventoried costs	(7.3)	2.1
Prepaid expenses and other assets	(27.3)	(18.8)
Operating lease liabilities	(5.7)	(6.1)
Accounts payable	17.5	(3.6)
Accrued expenses	9.1	0.0
Accrued compensation	0.0	(1.5)
Billings in excess of costs and earnings on uncompleted contracts	(5.1)	(21.0)
Income tax receivable and payable	(0.9)	4.4
Other liabilities	(1.4)	0.8
Net cash used in operating activities	(40.9)	(2.0)
Investing activities:
Cash paid for acquisitions, net of cash acquired	0.0	(11.5)
Capital expenditures	(43.1)	(29.3)
Net cash used in investing activities	(43.1)	(40.8)
Financing activities:
Proceeds from the issuance of common stock, net of issuance costs	555.9	330.7
Borrowing under credit facility	0.0	10.0
Repayment under credit facility and term loan	(5.0)	(47.5)
Payments under finance leases	(0.9)	(0.7)
Payments of employee taxes withheld from share-based awards	(18.3)	(17.1)
Proceeds from shares issued under equity plans	4.6	3.6
Net cash provided by financing activities	536.3	279.0
Net cash provided	452.3	236.2
Effect of exchange rate changes on cash and cash equivalents	2.0	(0.8)
Net increase in cash and cash equivalents	454.3	235.4
Cash and cash equivalents at beginning of period	329.3	72.8
Cash and cash equivalents at end of period	783.6	308.2
Non-cash investing and financing activities:
Financing lease obligation incurred	0.0	16.8
Capital expenditures included in accounts payable and accrued expenses	4.9	2.5
Common stock issuance for purchase of noncontrolling interests	0.0	11.3
Common stock issuance for acquisition	$ 36.6	$ 0.0