Commitments and Contingencies - Other Commitments and Contingencies (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($) project customer	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Loss Contingencies [Line Items]
Line of credit facility, letters of credit issued	$ 81,100,000		$ 82,100,000
Cash and cash equivalents	249,326,000		529,561,000
Indemnities, accrued project close-out liabilities	$ 20,000,000		$ 20,000,000
Number of customers | customer	965
Ten Largest Customers | Revenue Benchmark | Customer Concentration Risk
Loss Contingencies [Line Items]
Concentration risk, percentage of total	43.00%	39.00%
One Customer | Accounts Receivable, Net, Less Deferred Revenue | Customer Concentration Risk
Loss Contingencies [Line Items]
Concentration risk, percentage of total			10.00%
Pension | Infrastructure Energy Alternatives, Inc.
Loss Contingencies [Line Items]
Multiemployer plans, withdrawal obligation, monthly payment amount	$ 10,000
Withdrawal liability	1,700,000		$ 1,800,000
Self-Insurance | Workers' Compensation, General and Automobile Policies
Loss Contingencies [Line Items]
Self-insurance reserve	219,400,000		209,700,000
Self-Insurance | Employee Group Medical Claims
Loss Contingencies [Line Items]
Self-insurance reserve	5,500,000		4,100,000
Other Long-Term Liabilities | Self-Insurance | Workers' Compensation, General and Automobile Policies
Loss Contingencies [Line Items]
Self-insurance reserve, non-current	152,800,000		141,000,000
Corporate Joint Venture
Loss Contingencies [Line Items]
Payments for advance to affiliate	0	$ 300,000
Payable to affiliate	500,000		500,000
Cash and cash equivalents	$ 45,900,000		38,100,000
Corporate Joint Venture | Joint Venture Civil Construction Project
Loss Contingencies [Line Items]
Number of joint ventures | project	5
Corporate Joint Venture | Minimum | Joint Ventures That Provide Electrical Transmission Infrastructure Services
Loss Contingencies [Line Items]
Proportionately consolidated non-controlled joint venture, ownership percentage	85.00%
Corporate Joint Venture | Minimum | Joint Venture Civil Construction Project
Loss Contingencies [Line Items]
Proportionately consolidated non-controlled joint venture, ownership percentage	25.00%
Corporate Joint Venture | Maximum | Joint Ventures That Provide Electrical Transmission Infrastructure Services
Loss Contingencies [Line Items]
Proportionately consolidated non-controlled joint venture, ownership percentage	90.00%
Corporate Joint Venture | Maximum | Joint Venture Civil Construction Project
Loss Contingencies [Line Items]
Proportionately consolidated non-controlled joint venture, ownership percentage	50.00%
Captive Insurance Company
Loss Contingencies [Line Items]
Cash and cash equivalents	$ 1,300,000		1,200,000
Performance and Payment Bonds
Loss Contingencies [Line Items]
Bonded projects, estimated costs to complete	2,200,000,000		1,600,000,000
Commercial and/or Financial Standby | Self-Insurance | Workers' Compensation, General and Automobile Policies
Loss Contingencies [Line Items]
Line of credit facility, letters of credit issued	9,600,000		9,600,000
Surety Bonds | Self-Insurance | Workers' Compensation
Loss Contingencies [Line Items]
Guarantor obligations, maximum exposure, undiscounted	191,000,000		192,700,000
Subsidiaries | Performance and Payment Bonds
Loss Contingencies [Line Items]
Guarantor obligations, maximum exposure, undiscounted	6,600,000,000		5,600,000,000
Subsidiaries | Performance and Payment Bonds | Corporate Joint Venture
Loss Contingencies [Line Items]
Guarantor obligations, maximum exposure, undiscounted	$ 823,300,000		$ 368,300,000