Contracts in Progress - Remaining Performance Obligation (Details) $ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction
Performance obligations expected to be satisfied	$ 364.8
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction
Performance obligations expected to be satisfied	$ 328.6
Performance obligations expected to be satisfied, percentage	90.00%
Performance obligations expected to be satisfied, expected timing	12 months