LOANS, TROUBLED DEBT RESTRUCTURING (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) Loan	Dec. 31, 2015 USD ($) Loan	Dec. 31, 2014 USD ($) Loan
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans (in loan) \| Loan		13	10	15
Pre-Modification Recorded Balance		$ 2,320,000	$ 301,000	$ 1,676,000
Post-Modification Recorded Balance		2,393,000	304,000	1,676,000
Loans modified that subsequently defaulted		0	0	0
Modified impaired loans without a valuation allowance		881,000	147,000
Modified impaired loans with valuation allowance		1,168,000	125,000
Subsequent Event
Loan modifications classified as troubled debt restructurings [Abstract]
Loans modified that subsequently defaulted	$ 1,236,000
Federal Home Loan Mortgage Corporation and Other Investors
Loan modifications classified as troubled debt restructurings [Abstract]
Unpaid principal balances of loans sold and serviced for the Federal Home Loan Mortgage Corporation		$ 100,982,000	$ 111,837,000	$ 120,433,000
Commercial & industrial
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans (in loan) \| Loan		0	0	8
Pre-Modification Recorded Balance		$ 0	$ 0	$ 658,000
Post-Modification Recorded Balance		$ 0	$ 0	$ 340,000
Commercial, secured by real estate
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans (in loan) \| Loan		4	1	2
Pre-Modification Recorded Balance		$ 2,142,000	$ 75,000	$ 896,000
Post-Modification Recorded Balance		$ 2,215,000	$ 74,000	$ 1,214,000
Residential real estate
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans (in loan) \| Loan		6	7	2
Pre-Modification Recorded Balance		$ 139,000	$ 217,000	$ 82,000
Post-Modification Recorded Balance		$ 139,000	$ 221,000	$ 82,000
Consumer
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans (in loan) \| Loan		3	2	3
Pre-Modification Recorded Balance		$ 39,000	$ 9,000	$ 40,000
Post-Modification Recorded Balance		$ 39,000	$ 9,000	$ 40,000

Financing Receivable, Modifications, with No Related Allowance, Recorded Investment

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Financing Receivable, Modifications, with Related Allowance, Recorded Investment

+ References

No definition available.

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Unpaid Principal Balance Of Loans Serviced For Others

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953682-111524

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