GOODWILL AND INTANGIBLE ASSETS - Changes in carrying values of goodwill and intangible assets (Details) - Changes in carrying values of goodwill and intangible assets - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill
Balance, beginning of period	$ 13,815	$ 12,552	$ 12,552
Additions		1,263
Impairment
Balance, end of period	13,815	13,815	12,552
Core Deposit Intangibles
Cost, beginning of period	5,881	5,248	5,248
Additions		633
Impairment
Cost, end of period	5,881	5,881	5,248
Amortization, beginning of period	(4,044)	(3,511)	(2,910)
Amortization	(454)	(533)	(601)
Amortization, end of period	(4,498)	(4,044)	(3,511)
Core deposit intangibles, net	$ 1,383	$ 1,837	$ 1,737

Amount of significant additions in the period in other assets (current, noncurrent, or unclassified).

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The amount of expense recognized in the current period that reflects the allocation of capitalized costs associated with acquisition of business. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, from an acquisition.

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Amount after impairment of indefinite-lived intangible assets classified as other. Excludes financial assets and goodwill.

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Amount after accumulated amortization of finite-lived and indefinite-lived intangible assets classified as other.

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