SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE AND OTHER BORROWED FUNDS (Details) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Other borrowed funds disclosures
Borrowings outstanding	$ 440,502,000	$ 330,173,000
Average interest rate of outstanding balances	2.88%
Federal Home Loan Bank advances maturity period	2 years	1 year
Federal Home Loan Bank advances
Other borrowed funds disclosures
Borrowings outstanding	$ 437,000,000	$ 325,000,000
Total borrowing capacity available	670,300,000	$ 948,200,000
Average interest rate of outstanding balances		1.41%
Repurchase agreements
Other borrowed funds disclosures
Borrowings outstanding	3,502,000	$ 5,173,000
Federal Reserve Bank
Other borrowed funds disclosures
Borrowings outstanding	0	0
Available borrowing capacity	524,400,000	384,500,000
Federal Funds Purchased
Other borrowed funds disclosures
Federal Funds Purchased outstanding	$ 0	$ 0

Represents the maturity period for Federal Home Loan Bank advances.

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- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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The calculated weighted average interest rate for Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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- Definition

Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(3)(a))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Name Accounting Standards Codification
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-Section 45
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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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.

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