Fair Value of Financial Instruments - Other Investments - Other Equity Method Investments - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Equity method investments, equity in earnings (losses)	$ 6,777,000	$ 7,346,000
Equity method investments, net investment	$ 280,000,000		$ 267,000,000
Confluence
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Equity method investments, ownership percentage	75.00%
Equity method investments, equity contributions	$ 1,700,000	400,000
Equity method investments, equity in earnings (losses)	$ (200,000)	(100,000)
Confluence | Maximum
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Financing commitments		2,500,000
FM Tech
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Equity method investments, ownership percentage	50.00%
Equity method investments, net investment	$ 17,000,000		17,000,000
Telecommunications Equity Method Investees
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Equity method investments, equity contributions	500,000	2,000,000
Equity method investments, equity in earnings (losses)	(300,000)	(300,000)
Equity method investments, net investment	20,000,000		20,000,000
Payments for advance to affiliate	0	200,000
Telecommunications Equity Method Investees | Subcontracting Arrangements
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Expenses, related party	1,000,000	1,800,000
Payables, related party			300,000
Telecommunications Equity Method Investees | Employee Leasing and Advanced Receivable Arrangement
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Receivables, related party	$ 700,000		900,000
Certain Entities, Each Accounted for Using Equity Method Investments
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Equity method investments, ownership percentage	49.00%
Equity method investments, equity in earnings (losses)	$ 100,000
Equity method investments, net investment		$ 4,000,000	4,000,000
Expenses, related party	3,600,000
Payables, related party	100,000
Line of credit, amount drawn	8,500,000
Certain Entities, Each Accounted for Using Equity Method Investments | Other Current Assets
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items]
Line of credit, amount drawn	$ 400,000		$ 400,000