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RESTRUCTURING (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($) employee	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Restructuring cost and reserve
Restructuring charges			$ 1,163	$ 0	$ 0
Retail customer service workforce optimization plan
Restructuring cost and reserve
Severance costs		$ 1,100
Restructuring charges		$ 1,200
Number of employee reduced in bank branch network | employee		99
Retail customer service workforce optimization plan | Forecast
Restructuring cost and reserve
Severance costs	$ 100

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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