Number of offices included in Nature of Operations disclosure.

No definition available.

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- References

No definition available.

+ Details

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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

The aggregate amount of expenditures for salaries, wages, profit sharing and incentive compensation, and other employee benefits, including equity-based compensation, and pension and other postretirement benefit expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details) $ in Thousands	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) banking_office segment	Sep. 30, 2016 USD ($)	Dec. 31, 2016 segment
Accounting Policies [Abstract]
Number of banking offices \| banking_office				34
Number of reportable segments \| segment				1		3
Change in Accounting Estimate [Line Items]
Salaries and employee benefits	$ 30,216		$ 37,133	$ 96,007	$ 103,347
Reversal of Excess Accrual
Change in Accounting Estimate [Line Items]
Salaries and employee benefits		$ 7,800