BUSINESS COMBINATIONS - Changes to Goodwill Subsequent to Acquisition (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($)
Business Acquisition [Line Items]
Goodwill, beginning balance	$ 472,828
Goodwill, ending balance	883,637
BMBC
Business Acquisition [Line Items]
Goodwill, beginning balance	414,337
Effect of sale of BMTIA business	(8,101)
Goodwill, ending balance	410,809
BMBC \| Deferred income taxes
Business Acquisition [Line Items]
Goodwill adjustments	1,870
BMBC \| Intangibles
Business Acquisition [Line Items]
Goodwill adjustments	1,500
BMBC \| Deposits
Business Acquisition [Line Items]
Goodwill adjustments	(149)
BMBC \| Other liabilities
Business Acquisition [Line Items]
Goodwill adjustments	$ 1,352

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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