Segment Reporting - Disaggregation of Revenues (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	$ 968.3	$ 968.3
Commercial
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	675.5	672.2
Commercial | Consumer and Industrial Sector [Member]
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	224.0	214.2
Commercial | Technology, Media, and Telecommunications Sector [Member]
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	138.2	133.2
Commercial | Financial Services Sector [Member]
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	126.8	134.4
Commercial | Healthcare Sector [Member]
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	116.1	107.4
Commercial | Business Services Sector [Member]
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	70.4	83.0
Federal Government
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	292.8	296.1
Federal Government | Firm-fixed-price
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	90.2	90.0
Federal Government | T&M
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	106.0	126.1
Federal Government | Cost reimbursable
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	96.6	80.0
Other Federal [Member] | Federal Government
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	32.5	31.1
Department of Homeland Security [Member] | Federal Government
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	84.6	74.1
Federal Civilian [Member] | Federal Government
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	54.6	62.0
Department of Defense & Intelligence Agencies [Member] | Federal Government
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Revenues	$ 121.1	$ 128.9