SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - INTANGIBLE ASSETS AND SEGMENTS (Details) $ in Thousands		12 Months Ended
Jul. 24, 2015 USD ($) shares	Dec. 31, 2016 segment
Operating Segments
Number of reportable operating segments \| segment		1
Acquisition
Total purchase price net of capital stock issuance cost	$ 7,939
Minimum
Intangible Assets
Useful life of core deposit intangible assets		10 years
Maximum
Intangible Assets
Useful life of core deposit intangible assets		15 years
Madison Financial Corp
Acquisition
Payment for fractional shares	3
Value assigned	$ 7,900
Share issuance \| shares	263,361
Transaction and integration costs	$ 858

The cash outflow associated with the payment of partial shares with the acquisition of business during the period.

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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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Number of shares of equity interests issued or issuable to acquire entity.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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-Name Accounting Standards Codification
-Topic 805
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-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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