Summary of Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) Segment	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Contract payment term description	contracts typically contain billing terms that provide for invoicing monthly or upon completion of milestones, and payment on a net 30-day basis.
Contracts payment, term	30 days
Number of reportable segments | Segment	1
Goodwill, impaired, accumulated impairment loss	$ 0
Goodwill, impairment loss	$ 0
Number of operating segments | Segment	1
Revenue	$ 1,779,964,000	$ 1,553,048,000	$ 1,506,875,000
Foreign financial institutions, actual deposits	8,400,000	20,100,000
Domestic bank accounts exceeded FDIC insurance limit	5,200,000
Federal Government Agencies And Departments
Summary Of Significant Accounting Policies [Line Items]
Revenue	$ 980,400,000	$ 735,000,000.0	$ 667,000,000.0
Federal Government Agencies And Departments | Customer Concentration Risk | Sales Revenue, Net
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	55.00%	47.00%	44.00%
International Clients | Geographic Concentration Risk | Sales Revenue, Net
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	8.00%	11.00%	13.00%
International | Geographic Concentration Risk | Long-Lived Assets
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	7.00%	15.00%
Other Assets
Summary Of Significant Accounting Policies [Line Items]
Capitalized software, net of accumulated amortization	$ 19,000,000.0	$ 14,500,000
Indirect and Selling Expenses
Summary Of Significant Accounting Policies [Line Items]
Impairment expense	$ 8,400,000	$ 7,900,000	$ 3,100,000
Minimum
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful life	2 years
Finite-lived intangible asset, useful life	1 year
Minimum | Other Assets
Summary Of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life	3 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful life	7 years
Finite-lived intangible asset, useful life	10 years
Insured domestic bank accounts	$ 250,000
Maximum | Other Assets
Summary Of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life	5 years