BRANCH RESTRUCTURING COSTS (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($) item	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) item	Sep. 30, 2020 USD ($)
BRANCH RESTRUCTURING COSTS
Number of branches combined into existing branches \| item	5		5
Restructuring costs \| $	$ 4.5	$ 0.0	$ 6.2	$ 0.0

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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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration