BUSINESS COMBINATIONS - Summary of Segment Allocation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Business Combination, Goodwill, Reportable Segment Assignment [Line Items]
Goodwill	$ 1,876	$ 1,472,652
Financial Services
Business Combination, Goodwill, Reportable Segment Assignment [Line Items]
Goodwill	1,876	1,458,747
Financial Services \| IDG Acquisition and Other Acquisitions
Business Combination, Goodwill, Reportable Segment Assignment [Line Items]
Goodwill	1,876	25,237
Total	2,762	35,751
Financial Services \| Client lists \| IDG Acquisition and Other Acquisitions
Business Combination, Goodwill, Reportable Segment Assignment [Line Items]
Intangibles	886	10,514
Benefits and Insurance Services
Business Combination, Goodwill, Reportable Segment Assignment [Line Items]
Goodwill	0	13,905
Benefits and Insurance Services \| IDG Acquisition and Other Acquisitions
Business Combination, Goodwill, Reportable Segment Assignment [Line Items]
Goodwill	0	2,345
Total	0	4,989
Benefits and Insurance Services \| Client lists \| IDG Acquisition and Other Acquisitions
Business Combination, Goodwill, Reportable Segment Assignment [Line Items]
Intangibles	$ 0	$ 2,644

Business Combination, Aggregated Goodwill And Intangible Assets Acquired

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- Definition

Amount of identifiable finite-lived intangible asset acquired in business combination and recognized at acquisition date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 350
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