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COMMITMENTS, CONTINGENCIES AND OFF BALANCE SHEET RISK - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Reserve for credit risk inherent in off balance sheet credit commitments	$ 2,900		$ 2,900		$ 2,800
Credit loss, liability, provision (recovery) on off-balance sheet credit exposures	400	$ 100	100	$ 500
Equity method investments	5,505		5,505		7,979
Clean Energy LLC
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Remaining commitment	5,600		5,600
Equity method investments					2,400
Property Assessed Clean Energy Commitments \| Pace Funding Group LLC
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Remaining commitment	77,200		77,200
Property Assessed Clean Energy Commitments \| Allectrify PBC
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Remaining commitment	79,500		79,500
Commitments to extend credit
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Other commitment	70,000		70,000		70,000
Standby letters of credit
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Other commitment	$ 300		$ 300		$ 300