v3.20.1

LOANS AND ALLOWANCE FOR LOAN LOSSES - Impaired financing receivables by class of loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Average Recorded Investment	$ 4,322	$ 3,739
Interest Income Recognized	191	123
Interest Income Recognized on Cash Basis	42	64
Residential real estate [Member]
Average Recorded Investment	734	819
Interest Income Recognized	34	34
Interest Income Recognized on Cash Basis	26	28
Commercial real estate [Member]
Average Recorded Investment	2,704	2,920
Interest Income Recognized	107	89
Interest Income Recognized on Cash Basis	11	$ 36
Home equity lines of credit [Member]
Average Recorded Investment	167
Interest Income Recognized on Cash Basis	5
Commercial loan [Member]
Average Recorded Investment	717
Interest Income Recognized	$ 50

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

+ Details

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- Definition

Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

+ Details

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Wellesley Bancorp, Inc. 10-K