LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES - Summary of recorded investment amount and related allowance for losses of impaired loans (Details)	9 Months Ended
	Sep. 30, 2019 USD ($) borrower loan	Sep. 30, 2018 borrower	Dec. 31, 2018 USD ($)
Financing Receivable, Impaired [Line Items]
Loans outstanding	$ 700,000
Number of borrowers | borrower	47	43
30-89 Days Past Due
Financing Receivable, Impaired [Line Items]
Loans outstanding	$ 652,000		$ 1,726,000
30-89 Days Past Due | Substandard
Financing Receivable, Impaired [Line Items]
Loans outstanding	$ 700,000
Consumer
Financing Receivable, Impaired [Line Items]
Number of loans | loan	2
Number of borrowers | borrower	1
Amount of consumer and indirect loans, outstanding	$ 41,641
Amount of consumer and indirect loans, specific reserves	15,260
Consumer | 30-89 Days Past Due
Financing Receivable, Impaired [Line Items]
Loans outstanding	54,000		216,000
Commercial | 30-89 Days Past Due
Financing Receivable, Impaired [Line Items]
Loans outstanding			$ 86,000
Commercial | 30-89 Days Past Due | Substandard
Financing Receivable, Impaired [Line Items]
Loans outstanding	195,000
Commercial Real Estate | 30-89 Days Past Due | Substandard
Financing Receivable, Impaired [Line Items]
Loans outstanding	$ 546,000