Revenue - Disaggregation of Revenue by Performance Obligation (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Disaggregation of revenue by performance obligation
Revenue	$ 989,399	$ 880,701
Management fee revenue - policy issuance and renewal services
Disaggregation of revenue by performance obligation
Revenue	755,049	665,686
Management fee revenue - policy issuance and renewal services \| Transferred At Point in Time
Disaggregation of revenue by performance obligation
Revenue	755,049	665,686
Administrative services \| Transferred Over Time
Disaggregation of revenue by performance obligation
Revenue	227,918	208,501
Management fee revenue - administrative services
Disaggregation of revenue by performance obligation
Revenue	17,645	16,934
Management fee revenue - administrative services \| Transferred Over Time
Disaggregation of revenue by performance obligation
Revenue	17,645	16,934
Administrative services reimbursement revenue
Disaggregation of revenue by performance obligation
Revenue	210,273	191,567
Administrative services reimbursement revenue \| Transferred Over Time
Disaggregation of revenue by performance obligation
Revenue	$ 210,273	$ 191,567

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

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+ Details