GOODWILL AND OTHER INTANGIBLE ASSETS - Schedule of Goodwill (Detail) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Roll Forward of Gross Goodwill
Beginning balance	$ 963,710	$ 963,710
Additions from acquisitions	0	0
Ending gross goodwill balance	963,710	963,710
Roll Forward of Accumulated Goodwill Impairment
Beginning balance	95,000	95,000
Impairment	0	0
Ending accumulated goodwill impairment	95,000	95,000
Goodwill	868,710	868,710	$ 868,710
Capital Markets
Roll Forward of Gross Goodwill
Beginning balance	524,189	524,189
Additions from acquisitions	0	0
Ending gross goodwill balance	524,189	524,189
Roll Forward of Accumulated Goodwill Impairment
Beginning balance	95,000	95,000
Impairment	0	0
Ending accumulated goodwill impairment	95,000	95,000
Goodwill	429,189	429,189
Servicing and Asset Management
Roll Forward of Gross Goodwill
Beginning balance	439,521	439,521
Additions from acquisitions	0	0
Ending gross goodwill balance	439,521	439,521
Roll Forward of Accumulated Goodwill Impairment
Impairment	0	0
Goodwill	439,521	439,521
Corporate
Roll Forward of Accumulated Goodwill Impairment
Goodwill	$ 0	$ 0

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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