Fair Value of Financial Instruments - Other Investments - Other Equity Investments (Details) - USD ($)	12 Months Ended			36 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2023
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Equity method investments, net investment	$ 319,000,000	$ 306,000,000		$ 319,000,000
Equity method investments, equity contributions	300,000
Equity method investments, equity in earnings (losses)	30,697,000	28,836,000	$ 33,830,000
Subcontracting Arrangements | Related Party
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Payables, related party	1,100,000	300,000		1,100,000
Receivables, related party	400,000	400,000		400,000
Telecommunications Equity Method Investees
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Equity method investments, net investment	21,000,000	21,000,000		21,000,000
Equity method investments, equity contributions	0	1,000,000	2,000,000
Equity method investments, equity in earnings (losses)	400,000	(300,000)	(700,000)
Telecommunications Equity Method Investees | Subcontracting Arrangements | Related Party
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Payments, related party	1,800,000	7,600,000	9,900,000
Payables, related party	100,000	200,000		100,000
Telecommunications Equity Method Investees | Employee Leasing and Advanced Receivable Arrangement
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Payments, related party		3,300,000	200,000
Telecommunications Equity Method Investees | Employee Leasing and Advanced Receivable Arrangement | Related Party
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Receivables, related party	4,000,000	3,800,000		4,000,000
Telecommunications Equity Method Investees | Employee Leasing Expense Arrangement
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Payments, related party	0
Telecommunications Equity Method Investees | Advanced Receivable Arrangement
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Payments, related party	700,000
FM Tech
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Equity method investments, net investment	$ 18,000,000	18,000,000		$ 18,000,000
Equity method investment, ownership percentage	50.00%			50.00%
FM Tech | Equity Method Investments
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Financing commitments	$ 3,000,000	3,000,000		$ 3,000,000
FM Tech | Maximum | Equity Method Investments
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Financing commitments	7,000,000			7,000,000
Certain Entities, Each Accounted for Using Equity Method Investments
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Equity method investments, net investment	3,000,000	3,000,000		$ 3,000,000
Equity method investments, equity in earnings (losses)	(200,000)	(400,000)	0
Payments, related party	$ 900,000	$ 6,600,000
Equity method investment, ownership percentage	49.00%	49.00%		49.00%
Borrowing availability	$ 3,000,000	$ 4,500,000		$ 3,000,000
Certain Entities, Each Accounted for Using Equity Method Investments | Other Current Assets
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Borrowing availability	0	600,000		0
Confluence
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Financing commitments			2,500,000
Equity method investments, equity contributions	200,000	200,000	1,700,000	$ 2,100,000
Equity method investments, equity in earnings (losses)	(200,000)	$ (400,000)	$ (700,000)
Equity method investment, ownership percentage			75.00%
AVCT
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Unrealized fair value measurement gains, net, AVCT shares	$ (200,000)