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Business Segments and Geographic Information - Additional Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) Segment	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Schedule Of Equity Method Investments [Line Items]
Number of reportable business segments \| Segment			4
Equity in earnings (losses) of affiliates, net of income tax provision	$ 1,942	$ 2,699	$ 4,007	$ 4,959
SACS
Schedule Of Equity Method Investments [Line Items]
Ownership percentage in entity			50.00%
Equity in earnings (losses) of affiliates, net of income tax provision			$ 1,800	1,900
Investment in joint venture	11,100		11,100		$ 11,100
GEO Amey
Schedule Of Equity Method Investments [Line Items]
Equity in earnings (losses) of affiliates, net of income tax provision			2,200	$ 3,100
Advances to affiliate	$ 8,900		$ 8,900		$ 11,800