Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Payables And Accruals [Abstract]
Deposits	$ 21,088	$ 9,881
Restricted contract funds	12,165	68,138
Accrued IT and software licensing costs	1,702	2,157
Accrued taxes and insurance premiums	5,267	4,327
Accrued facilities rental and lease exit costs	1,291	780
Accrued interest	212	214
Accrued professional services	3,068	2,094
Accrued dividends	2,643	2,641
Contingent and contractual liabilities from acquisitions	1,245	683
Interest rate swap liability - current	3,026	3,693
Other accrued expenses and current liabilities	9,789	6,300
Total accrued expenses and other current liabilities	$ 61,496	$ 100,908