SHAREHOLDERS' EQUITY AND EARNINGS PER COMMON SHARE SHAREHOLDERS' EQUITY AND EARNINGS PER COMMON SHARE (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Capital [Abstract]
Total capital to risk-weighted assets, actual amount	$ 803,618	$ 686,489
Total capital to risk-weighted assets, actual percent	11.87%	11.91%
Total capital to risk-weighted assets, minimum capital requirement, amount	$ 541,603	$ 461,231
Total capital to risk-weighted assets, minimum capital requirement, percent	8.00%	8.00%
Total capital to risk-weighted assets, minimum to be well capitalized under prompt corrective action provisions, amount	$ 677,004	$ 576,539
Total capital to risk-weighted assets, minimum to be well capitalized under prompt corrective action provisions, percent	10.00%	10.00%
Common Equity Tier One Risk Based Capital to Risk Weighted Assets, Amount	$ 670,120	$ 564,878
Common Equity Tier One Risk Based Capital to Risk Weighted Assets	9.90%	9.80%
Common Equity Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets, Amount	$ 304,652	$ 259,443
Common Equity Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	4.50%	4.50%
Common Entity Tier 1 Capital To Risk Weighted Assets, Capital Required to be Well Capitalized	$ 440,053	$ 374,750
Common Entity Tier 1 Capital To Risk Weighted Assets, Capital Required to be Well Capitalized, Percent	6.50%	6.50%
Tier One Risk Based Capital [Abstract]
Tier 1 capital risk-weighted assets, amount	$ 681,500	$ 573,033
Tier 1 capital risk-weighted assets, percent	10.07%	9.94%
Tier 1 capital risk-weighted assets, minimum capital requirement, amount	$ 406,202	$ 345,924
Tier 1 capital risk-weighted assets, minimum capital requirement, percent	6.00%	6.00%
Tier 1 capital risk-weighted assets, minimum to be well capitalized under prompt corrective action provisions, amount	$ 541,603	$ 461,231
Tier 1 capital risk-weighted assets, minimum to be well capitalized under prompt corrective action provisions, percent	8.00%	8.00%
Tier One Leverage Capital [Abstract]
Tier 1 capital to average assets, amount	$ 681,500	$ 573,033
Tier 1 capital to average assets, percent	7.88%	7.71%
Tier 1 capital to average assets, minimum capital requirement, amount	$ 270,802	$ 297,420
Tier 1 capital to average assets, minimum capital requirement, percent	4.00%	4.00%
Tier 1 capital to average assets, minimum to be well capitalized under prompt corrective action provisions, amount	$ 338,502	$ 371,775
Tier 1 capital to average assets, minimum to be well capitalized under prompt corrective action provisions, percent	5.00%	5.00%
Subsidiaries
Capital [Abstract]
Total capital to risk-weighted assets, actual amount	$ 756,792	$ 642,866
Total capital to risk-weighted assets, actual percent	11.21%	11.16%
Total capital to risk-weighted assets, minimum capital requirement, amount	$ 539,893	$ 460,882
Total capital to risk-weighted assets, minimum capital requirement, percent	8.00%	8.00%
Total capital to risk-weighted assets, minimum to be well capitalized under prompt corrective action provisions, amount	$ 674,866	$ 576,103
Total capital to risk-weighted assets, minimum to be well capitalized under prompt corrective action provisions, percent	10.00%	10.00%
Common Equity Tier One Risk Based Capital to Risk Weighted Assets, Amount	$ 672,244	$ 569,131
Common Equity Tier One Risk Based Capital to Risk Weighted Assets	9.96%	9.88%
Common Equity Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets, Amount	$ 303,690	$ 259,246
Common Equity Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	4.50%	4.50%
Common Entity Tier 1 Capital To Risk Weighted Assets, Capital Required to be Well Capitalized	$ 438,663	$ 374,467
Common Entity Tier 1 Capital To Risk Weighted Assets, Capital Required to be Well Capitalized, Percent	6.50%	6.50%
Tier One Risk Based Capital [Abstract]
Tier 1 capital risk-weighted assets, amount	$ 672,244	$ 569,131
Tier 1 capital risk-weighted assets, percent	9.96%	9.88%
Tier 1 capital risk-weighted assets, minimum capital requirement, amount	$ 404,920	$ 345,662
Tier 1 capital risk-weighted assets, minimum capital requirement, percent	6.00%	6.00%
Tier 1 capital risk-weighted assets, minimum to be well capitalized under prompt corrective action provisions, amount	$ 539,893	$ 460,882
Tier 1 capital risk-weighted assets, minimum to be well capitalized under prompt corrective action provisions, percent	8.00%	8.00%
Tier One Leverage Capital [Abstract]
Tier 1 capital to average assets, amount	$ 672,244	$ 569,131
Tier 1 capital to average assets, percent	7.84%	7.66%
Tier 1 capital to average assets, minimum capital requirement, amount	$ 269,920	$ 297,313
Tier 1 capital to average assets, minimum capital requirement, percent	4.00%	4.00%
Tier 1 capital to average assets, minimum to be well capitalized under prompt corrective action provisions, amount	$ 337,433	$ 371,641
Tier 1 capital to average assets, minimum to be well capitalized under prompt corrective action provisions, percent	5.00%	5.00%

Common Entity Tier 1 Capital To Risk Weighted Assets, Capital Required to be Well Capitalized

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The Common equity Tier 1 capital ratio (Common equity 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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Common Equity Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets, Amount

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

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Common Equity Tier One Risk Based Capital to Risk Weighted Assets, Amount

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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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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 required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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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 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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