ALLOWANCE FOR LOAN LOSSES: (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Allowance for Loan Losses:
Impaired loans	$ 7,113	$ 10,516
Allowance for Loan Losses Allocated	48	$ 737
Minimum outstanding balance of non-homogeneous loans to be individually evaluated as to credit risk	$ 100
Minimum
Allowance for Loan Losses:
Loan modification, reduction of stated interest rate	12 months
Loan modification, extension of maturity date	12 months
Maximum
Allowance for Loan Losses:
Loan modification, reduction of stated interest rate	5 years
Loan modification, extension of maturity date	10 years

Loan Modification, Extension of Maturity Date

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- Definition

Loan Modification, Reduction of Stated Interest Rate

+ References

No definition available.

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- Definition

Represents the minimum outstanding balance of loans to be individually reviewed and classified as to credit risk. Homogeneous loans (at all levels of outstanding balances) are not reviewed individually, but rather as part of a group.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ 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 (a)(3)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

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