LOANS - Narrative (Details) $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($) industry_concentration loan	Dec. 31, 2014 USD ($) loan	Dec. 31, 2013 USD ($)
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of industry segment concentration above threshold limit \| industry_concentration	1
Concentration risk of the loan portfolio (more than)	10.00%
Loans exposure in oil and gas industry	$ 264,700
Exposure in the oil and gas industry specified as percentage of total loans	20.90%
Loans on nonaccrual status	$ 50,051	$ 10,701
Loans with exposure in commercial real estate	528,000
Interest lost on nonaccrual loans	2,000	594	$ 518
Interest received on nonaccrual loans	$ 47	$ 105	$ 312
Number of loans with a pre-modification balance identified as a TDR \| loan	1	1
Pre-modification balance	$ 21,400	$ 1,200
Number of defaults on loans modified as TDRs \| loan	1	0
TDR defaulted on modified terms, total	$ 20,600
Real estate – commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans on nonaccrual status	$ 19,900
Percentage of loans on nonaccrual status	3.80%
Loans with exposure in commercial real estate	$ 471,100
Percentage of CRE loans secured by owner occupied commercial properties	54.00%
Oil and gas industry
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans on nonaccrual status	$ 27,400
Percentage of loans on nonaccrual status	10.40%

This line item represents the exposure in the oil and gas industry specified as a percentage of total loans.

No definition available.

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- Definition

Number of investment in financing receivables (before modification) modified by troubled debt restructurings.

+ References

No definition available.

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- Definition

Financing Receivable, Nonaccrual, Percent Past Due

+ References

No definition available.

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- Definition

This line item represents the interest received on nonaccrual loans.

+ References

No definition available.

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- Definition

This line item represents the loans exposure in the oil and gas industry.

+ References

No definition available.

+ Details

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- Definition

This line item represents the loans with exposure in the commercial real estate section.

+ References

No definition available.

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- Definition

This line item represents the number of industry segment concentration above threshold limit of the loan portfolio.

+ References

No definition available.

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- Definition

This line item represents the percentage of CRE loans secured by owner occupied commercial properties.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13531-108611

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- Definition

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

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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=35738203&loc=SL6953676-111524

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953682-111524

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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

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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- Definition

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.

+ References

No definition available.

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- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
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-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

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