SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - PREMISES AND EQUIPMENT (Details)	12 Months Ended
	Dec. 31, 2019
Buildings and improvements | Minimum
Premises and equipment, net
Estimated useful lives	25 years
Buildings and improvements | Maximum
Premises and equipment, net
Estimated useful lives	39 years
Furniture, fixtures and equipment | Minimum
Premises and equipment, net
Estimated useful lives	3 years
Furniture, fixtures and equipment | Maximum
Premises and equipment, net
Estimated useful lives	10 years
Leasehold improvements | Minimum
Premises and equipment, net
Estimated useful lives	3 years
Leasehold improvements | Maximum
Premises and equipment, net
Estimated useful lives	5 years