Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule II - Valuation and Qualifying Accounts [Roll Forward]
Balance at Beginning of Period	$ 158.5	$ 213.0	$ 158.8
Charges to Cost and Expense	28.1	49.5	23.6
Other Additions	0.0	0.0	69.9
(Deductions)	(38.4)	(104.0)	(39.3)
Balance at End of Period	148.2	158.5	213.0
Allowance for credit losses
Schedule II - Valuation and Qualifying Accounts [Roll Forward]
Balance at Beginning of Period	15.1	8.4	7.8
Charges to Cost and Expense	9.9	12.7	2.6
Other Additions	0.0	0.0	0.0
(Deductions)	(5.9)	(6.0)	(2.0)
Balance at End of Period	19.1	15.1	8.4
Allowance for unbilled receivables and project close-out liabilities
Schedule II - Valuation and Qualifying Accounts [Roll Forward]
Balance at Beginning of Period	83.0	117.0	96.8
Charges to Cost and Expense	8.6	34.0	9.4
Other Additions	0.0	0.0	40.3
(Deductions)	(27.2)	(68.0)	(29.5)
Balance at End of Period	64.4	83.0	117.0
Valuation allowance for deferred tax assets
Schedule II - Valuation and Qualifying Accounts [Roll Forward]
Balance at Beginning of Period	60.4	87.6	54.2
Charges to Cost and Expense	9.6	2.8	11.6
Other Additions	0.0	0.0	29.6
(Deductions)	(5.3)	(30.0)	(7.8)
Balance at End of Period	$ 64.7	$ 60.4	$ 87.6