Revenue - Asset-based Revenue disaggregated by Product and Service (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Disaggregation of Revenue [Line Items]
Asset Based Fees	$ 820,805	$ 695,241
Client cash
Disaggregation of Revenue [Line Items]
Asset Based Fees	445,325	392,031
Sponsorship Programs [Member]
Disaggregation of Revenue [Line Items]
Asset Based Fees	223,649	170,538
Recordkeeping Revenues [Member]
Disaggregation of Revenue [Line Items]
Asset Based Fees	$ 151,831	$ 132,672

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.

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+ Details