GOODWILL AND OTHER INTANGIBLE ASSETS - Intangible Assets and Goodwill (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Finite-Lived Intangible Assets, Net [Abstract]
Intangible assets, gross	$ 53,366	$ 42,944
Accumulated amortization	(28,313)	(23,089)
Total amortizing intangible assets	25,053	19,855
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Amount	56,614	49,971
Accumulated amortization	(28,313)	(23,089)
Net Carrying Amount	28,301	26,882
Goodwill, gross	363,436	363,436
Goodwill, Net	363,436	363,436	$ 370,223
Intangible projects in process
Indefinite-lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets	3,248	7,027
Core deposit intangibles
Finite-Lived Intangible Assets, Net [Abstract]
Intangible assets, gross	29,038	29,038
Accumulated amortization	(20,181)	(16,694)
Total amortizing intangible assets	8,857	12,344
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Accumulated amortization	$ (20,181)	$ (16,694)
Core deposit intangibles | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	5 years 6 months	6 years 6 months
Software
Finite-Lived Intangible Assets, Net [Abstract]
Intangible assets, gross	$ 10,422	$ 0
Accumulated amortization	(183)	0
Total amortizing intangible assets	10,239	0
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Accumulated amortization	$ (183)	0
Software | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	4 years 9 months 18 days
Other identifiable intangibles
Finite-Lived Intangible Assets, Net [Abstract]
Intangible assets, gross	$ 13,906	13,906
Accumulated amortization	(7,949)	(6,395)
Total amortizing intangible assets	5,957	7,511
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Accumulated amortization	$ (7,949)	$ (6,395)
Other identifiable intangibles | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	7 years 8 months 12 days	8 years 9 months 18 days