FAIR VALUE DISCLOSURES - Summary of Additional Qualitative Information (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Impaired loans \| Appraisal of collateral
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Valuation Techniques	Appraisal of collateral	Appraisal of collateral
Foreclosed real estate \| Appraisal of collateral
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Valuation Techniques	Appraisal of collateral	Appraisal of collateral
Mortgage servicing rights \| Discounted cash flows
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Valuation Techniques	Discounted cash flows
Fair Value, Measurements, Nonrecurring \| Impaired loans \| Appraisal of collateral
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Estimate	$ 9,841	$ 4,757
Fair Value, Measurements, Nonrecurring \| Impaired loans \| Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate range (percentage)	0.00%	6.00%
Fair Value, Measurements, Nonrecurring \| Impaired loans \| Minimum \| Appraisal of collateral
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate range (percentage)	0.00%	0.00%
Fair Value, Measurements, Nonrecurring \| Impaired loans \| Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate range (percentage)	41.00%	44.00%
Fair Value, Measurements, Nonrecurring \| Impaired loans \| Maximum \| Appraisal of collateral
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate range (percentage)	68.00%	70.00%
Fair Value, Measurements, Nonrecurring \| Foreclosed real estate \| Appraisal of collateral
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Estimate	$ 149	$ 175
Fair Value, Measurements, Nonrecurring \| Foreclosed real estate \| Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate range (percentage)	3.00%	5.00%
Fair Value, Measurements, Nonrecurring \| Foreclosed real estate \| Minimum \| Appraisal of collateral
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate range (percentage)	15.00%	10.00%
Fair Value, Measurements, Nonrecurring \| Foreclosed real estate \| Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate range (percentage)	6.00%	6.00%
Fair Value, Measurements, Nonrecurring \| Foreclosed real estate \| Maximum \| Appraisal of collateral
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate range (percentage)	100.00%	20.00%
Fair Value, Measurements, Nonrecurring \| Mortgage servicing rights \| Discounted cash flows
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Estimate	$ 2,532
Discount rate range (percentage)	9.55%
Fair Value, Measurements, Nonrecurring \| Mortgage servicing rights \| Weighted average CPR \| Discounted cash flows
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Weighted average CPR (percentage)	12.80%

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Rate at which loans or a loan portfolio are expected to prepay principal balances, used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Description of the inputs and valuation technique(s) used to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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