REGULATORY CAPITAL (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
The Bank [Member]
Total Capital
Total Capital (to risk-weighted assets)	$ 485,252	$ 392,305
Total Capital (to risk-weighted assets) ratio	14.34%	12.87%
Minimum Capital required to be well-capitalized	$ 338,327	$ 304,758
Minimum Capital required to be well-capitalized, ratio	10.00%	10.00%
Minimum amount of capital for adequacy purposes	$ 270,662	$ 243,806
Minimum amount of capital for adequacy purposes, ratio	8.00%	8.00%
Tier 1 Capital (to risk-weighted assets)
Tier 1 Capital (to risk-weighted assets)	$ 448,812	$ 360,097
Tier 1 Capital (to risk-weighted assets) ratio	13.27%	11.82%
Minimum Tier 1 Capital required to be well-capitalized	$ 270,662	$ 243,806
Minimum Tier 1 Capital required to be well-capitalized, ratio	8.00%	8.00%
Minimum amount of Tier 1 Capital for adequacy purposes	$ 202,996	$ 182,855
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	6.00%	6.00%
Common equity tier I
Common equity tier I (to risk-weighted assets)	$ 448,810	$ 360,094
Common equity tier I (to risk-weighted assets) ratio	13.27%	11.82%
Minimum common equity tier I required to be well-capitalized	$ 219,913	$ 198,093
Minimum common equity tier I required to be well-capitalized, ratio	6.50%	6.50%
Minimum amount of common equity tier I for adequacy purposes	$ 152,247	$ 137,141
Minimum amount of common equity tier I for adequacy purposes, ratio	4.50%	4.50%
Tier 1 Leverage Capital (to average assets)
Tier 1 Capital (to average assets)	$ 448,812	$ 360,097
Tier 1 Capital (to average assets) ratio	10.61%	9.31%
Minimum Tier 1 Capital required to be well-capitalized	$ 211,523	$ 193,430
Minimum Tier 1 Capital required to be well-capitalized, ratio	5.00%	5.00%
Minimum amount of Tier 1 Capital for adequacy purposes	$ 169,219	$ 154,744
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	4.00%	4.00%
The Bank [Member] \| Conservation Buffer [Member]
Total Capital
Minimum amount of capital for adequacy purposes	$ 312,953	$ 262,854
Minimum amount of capital for adequacy purposes, ratio	9.25%	8.625%
Tier 1 Capital (to risk-weighted assets)
Minimum amount of Tier 1 Capital for adequacy purposes	$ 245,287	$ 201,902
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	7.25%	6.625%
Common equity tier I
Minimum amount of common equity tier I for adequacy purposes	$ 194,538	$ 156,188
Minimum amount of common equity tier I for adequacy purposes, ratio	5.75%	5.125%
Tier 1 Leverage Capital (to average assets)
Minimum amount of Tier 1 Capital for adequacy purposes	$ 169,219	$ 154,744
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	4.00%	4.00%
Parent Company [Member]
Total Capital
Total Capital (to risk-weighted assets)	$ 502,334	$ 404,017
Total Capital (to risk-weighted assets) ratio	14.84%	13.25%
Minimum amount of capital for adequacy purposes	$ 270,866	$ 243,910
Minimum amount of capital for adequacy purposes, ratio	8.00%	8.00%
Tier 1 Capital (to risk-weighted assets)
Tier 1 Capital (to risk-weighted assets)	$ 382,870	$ 323,045
Tier 1 Capital (to risk-weighted assets) ratio	11.31%	10.60%
Minimum amount of Tier 1 Capital for adequacy purposes	$ 203,149	$ 182,933
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	6.00%	6.00%
Common equity tier I
Common equity tier I (to risk-weighted assets)	$ 382,868	$ 323,042
Common equity tier I (to risk-weighted assets) ratio	11.31%	10.60%
Minimum amount of common equity tier I for adequacy purposes	$ 152,362	$ 137,200
Minimum amount of common equity tier I for adequacy purposes, ratio	4.50%	4.50%
Tier 1 Leverage Capital (to average assets)
Tier 1 Capital (to average assets)	$ 382,870	$ 323,045
Tier 1 Capital (to average assets) ratio	9.04%	8.35%
Minimum amount of Tier 1 Capital for adequacy purposes	$ 169,318	$ 154,788
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	4.00%	4.00%
Parent Company [Member] \| Conservation Buffer [Member]
Total Capital
Minimum amount of capital for adequacy purposes	$ 313,189	$ 262,966
Minimum amount of capital for adequacy purposes, ratio	9.25%	8.625%
Tier 1 Capital (to risk-weighted assets)
Minimum amount of Tier 1 Capital for adequacy purposes	$ 245,472	$ 201,988
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	7.25%	6.625%
Common equity tier I
Minimum amount of common equity tier I for adequacy purposes	$ 194,685	$ 156,255
Minimum amount of common equity tier I for adequacy purposes, ratio	5.75%	5.125%
Tier 1 Leverage Capital (to average assets)
Minimum amount of Tier 1 Capital for adequacy purposes	$ 169,318	$ 154,788
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	4.00%	4.00%

Minimum amount of common equity tier I for adequacy purposes, ratio.

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The amount of total capital as defined in the regulations.

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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as adequately capitalized under regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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