COMMITMENTS AND CONTINGENCIES - Narrative (Details)	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2003
Minimum
Risk Participation Agreements [Abstract]
Risk participation agreements, average term	1 year
Maximum
Risk Participation Agreements [Abstract]
Risk participation agreements, average term	8 years
Marketing rights
Marketing Rights [Abstract]
Commitment period		25 years
Financial standby letters of credit
Letters of Credit [Abstract]
Letters of credit outstanding, term	ten years
Commercial letters of credit
Letters of Credit [Abstract]
Letters of credit outstanding, term	one year