Segment Information - Reconciliation of Operating Profit from Segments to Consolidated (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	$ 324,596	$ 287,789
Net corporate interest expense	(4,399)	(1,519)
Contingent earnout adjustments	(248)	(2,056)
Income before income taxes	16,001	7,582
Operating Segments
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Total segment operating earnings	28,993	15,540
Segment Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Unallocated corporate and shared costs, net	(4,119)	(2,995)
Net corporate interest expense	(4,399)	(1,519)
Stock option expense	(156)	(205)
Amortization of customer-relationship intangible assets	(1,899)	(1,726)
Contingent earnout adjustments	(248)	(2,056)
Non-service pension (costs) credits	(2,171)	(543)
Income before income taxes	16,001	7,582
North America Loss Adjusting
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	77,127	64,438
North America Loss Adjusting \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Total segment operating earnings	8,065	4,135
International Operations
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	91,863	89,272
International Operations \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Total segment operating earnings	3,035	3,067
Broadspire
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	81,182	76,454
Broadspire \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Total segment operating earnings	7,927	6,434
Platform Solutions
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	62,820	48,861
Platform Solutions \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Total segment operating earnings	9,966	8,038
Service
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	312,992	279,025
Service \| North America Loss Adjusting \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	77,127	64,438
Service \| International Operations
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	91,863	89,272
Service \| International Operations \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	91,863	89,272
Service \| Broadspire
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	81,182	76,454
Service \| Broadspire \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	81,182	76,454
Service \| Platform Solutions
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	62,820	48,861
Service \| Platform Solutions \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	62,820	48,861
Reimbursements
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	$ 11,604	$ 8,764

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