BUSINESS COMBINATIONS - Summary of Segment Allocation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Business Combination Segment Allocation [Line Items]
Goodwill	$ 1,472,652	$ 45,254
Financial Services
Business Combination Segment Allocation [Line Items]
Goodwill	1,458,747	41,322
Financial Services \| Other 2024 Acquisitions and 2023 Acquisitions
Business Combination Segment Allocation [Line Items]
Goodwill	25,237	41,322
Total	35,751	74,536
Financial Services \| Client lists \| Other 2024 Acquisitions and 2023 Acquisitions
Business Combination Segment Allocation [Line Items]
Intangibles	10,514	33,196
Financial Services \| Other intangibles \| Other 2024 Acquisitions and 2023 Acquisitions
Business Combination Segment Allocation [Line Items]
Intangibles	0	18
Benefits and Insurance Services
Business Combination Segment Allocation [Line Items]
Goodwill	13,905	3,932
Benefits and Insurance Services \| Other 2024 Acquisitions and 2023 Acquisitions
Business Combination Segment Allocation [Line Items]
Goodwill	2,345	3,932
Total	4,989	5,985
Benefits and Insurance Services \| Client lists \| Other 2024 Acquisitions and 2023 Acquisitions
Business Combination Segment Allocation [Line Items]
Intangibles	2,644	2,053
Benefits and Insurance Services \| Other intangibles \| Other 2024 Acquisitions and 2023 Acquisitions
Business Combination Segment Allocation [Line Items]
Intangibles	$ 0	$ 0

Business Combination, Aggregated Goodwill And Intangible Assets Acquired

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The amount of identifiable intangible assets recognized as of the acquisition date.

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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.

+ References

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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