Contract Assets and Liabilities - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Loss Contingencies [Line Items]
Revenue recognized	$ 8,800,000	$ 13,300,000	$ 105,600,000	$ 102,700,000
Aggregate claim recovery estimate included in contract assets and liability	58,700,000	36,100,000	58,700,000	36,100,000	$ 45,100,000
Contract retention, uncollectable amount			0
Performance Obligations [Member]
Loss Contingencies [Line Items]
Contracts Revenue	$ 43,500,000	$ 33,200,000	$ 84,800,000	$ 60,900,000