GOODWILL AND OTHER INTANGIBLE ASSETS - Gross Carrying Amounts and Accumulated Amortization (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 42,944	$ 42,944
Accumulated Amortization	(25,664)	(23,089)
Net Carrying Amount	17,280	19,855
Goodwill	363,436	363,436
Goodwill	363,436	363,436
Core deposit intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	29,038	29,038
Accumulated Amortization	(18,486)	(16,694)
Net Carrying Amount	$ 10,552	$ 12,344
Core deposit intangibles | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Life	6 years	6 years 6 months
Other identifiable intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 13,906	$ 13,906
Accumulated Amortization	(7,178)	(6,395)
Net Carrying Amount	$ 6,728	$ 7,511
Other identifiable intangibles | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Life	8 years 2 months 12 days	8 years 9 months 18 days