Segment Disclosures - Summary of Disaggregation of Revenue by Source (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Disaggregation of Revenue [Line Items]
Revenue	$ 494,297	$ 454,606
Financial Services
Disaggregation of Revenue [Line Items]
Revenue	372,630	343,086
Benefits and Insurance Services
Disaggregation of Revenue [Line Items]
Revenue	108,408	100,054
National Practices
Disaggregation of Revenue [Line Items]
Revenue	13,259	11,466
Accounting, tax, advisory and consulting
Disaggregation of Revenue [Line Items]
Revenue	372,630	343,086
Accounting, tax, advisory and consulting | Financial Services
Disaggregation of Revenue [Line Items]
Revenue	372,630	343,086
Accounting, tax, advisory and consulting | Benefits and Insurance Services
Disaggregation of Revenue [Line Items]
Revenue	0	0
Accounting, tax, advisory and consulting | National Practices
Disaggregation of Revenue [Line Items]
Revenue	0	0
Core benefits and insurance services
Disaggregation of Revenue [Line Items]
Revenue	105,205	96,617
Core benefits and insurance services | Financial Services
Disaggregation of Revenue [Line Items]
Revenue	0	0
Core benefits and insurance services | Benefits and Insurance Services
Disaggregation of Revenue [Line Items]
Revenue	105,205	96,617
Core benefits and insurance services | National Practices
Disaggregation of Revenue [Line Items]
Revenue	0	0
Non-core benefits and insurance services
Disaggregation of Revenue [Line Items]
Revenue	3,203	3,437
Non-core benefits and insurance services | Financial Services
Disaggregation of Revenue [Line Items]
Revenue	0	0
Non-core benefits and insurance services | Benefits and Insurance Services
Disaggregation of Revenue [Line Items]
Revenue	3,203	3,437
Non-core benefits and insurance services | National Practices
Disaggregation of Revenue [Line Items]
Revenue	0	0
Managed networking, hardware services
Disaggregation of Revenue [Line Items]
Revenue	10,188	8,954
Managed networking, hardware services | Financial Services
Disaggregation of Revenue [Line Items]
Revenue	0	0
Managed networking, hardware services | Benefits and Insurance Services
Disaggregation of Revenue [Line Items]
Revenue	0	0
Managed networking, hardware services | National Practices
Disaggregation of Revenue [Line Items]
Revenue	10,188	8,954
National practices consulting
Disaggregation of Revenue [Line Items]
Revenue	3,071	2,512
National practices consulting | Financial Services
Disaggregation of Revenue [Line Items]
Revenue	0	0
National practices consulting | Benefits and Insurance Services
Disaggregation of Revenue [Line Items]
Revenue	0	0
National practices consulting | National Practices
Disaggregation of Revenue [Line Items]
Revenue	$ 3,071	$ 2,512