Commitments and Contingencies (Details)	1 Months Ended	3 Months Ended
	Jan. 31, 2025 USD ($)	Mar. 31, 2025 USD ($) project customer	Mar. 31, 2024	Dec. 31, 2024 USD ($)
Loss Contingencies [Line Items]
Line of credit facility, letters of credit issued		$ 78,700,000		$ 81,700,000
Cash and cash equivalents		345,749,000		399,903,000
Indemnities, accrued project close-out liabilities		$ 20,000,000		20,000,000
Number of customers | customer		1,045
Pension
Loss Contingencies [Line Items]
Payments for withdrawal obligation	$ 1,300,000
Pension | Infrastructure Energy Alternatives, Inc.
Loss Contingencies [Line Items]
Multiemployer plans, withdrawal obligation, monthly payment amount		$ 10,000
Ten Largest Customers | Revenue Benchmark | Customer Concentration Risk
Loss Contingencies [Line Items]
Concentration risk, percentage of total		36.00%	43.00%
Self-Insurance | Workers' Compensation, General and Automobile Policies
Loss Contingencies [Line Items]
Self-insurance reserve		$ 254,900,000		251,000,000.0
Insurance receivables		24,600,000		24,400,000
Self-Insurance | Employee Group Medical Claims
Loss Contingencies [Line Items]
Self-insurance reserve		5,100,000		4,700,000
Other Long-Term Liabilities | Self-Insurance | Workers' Compensation, General and Automobile Policies
Loss Contingencies [Line Items]
Self-insurance reserve, non-current		188,100,000		184,100,000
Other Noncurrent Assets | Self-Insurance | Workers' Compensation, General and Automobile Policies
Loss Contingencies [Line Items]
Insurance receivables		21,600,000		21,400,000
Corporate Joint Venture
Loss Contingencies [Line Items]
Cash and cash equivalents		$ 38,500,000		46,700,000
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		$ 2,600,000		2,200,000
Performance and Payment Bonds
Loss Contingencies [Line Items]
Bonded projects, estimated costs to complete		2,100,000,000		2,200,000,000
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		8,700,000		8,700,000
Surety Bonds | Self-Insurance | Workers' Compensation
Loss Contingencies [Line Items]
Guarantor obligations, maximum exposure, undiscounted		190,200,000		196,300,000
Subsidiaries | Performance and Payment Bonds
Loss Contingencies [Line Items]
Guarantor obligations, maximum exposure, undiscounted		7,500,000,000		7,600,000,000
Subsidiaries | Performance and Payment Bonds | Corporate Joint Venture
Loss Contingencies [Line Items]
Guarantor obligations, maximum exposure, undiscounted		$ 842,900,000		$ 838,700,000