SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE AND OTHER BORROWED FUNDS (Details) - USD ($)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Other borrowed funds disclosures
Federal Home Loan Bank advances	$ 325,000,000	$ 150,000,000
Repurchase agreements	5,173,000	3,493,000
Borrowings outstanding	$ 330,173,000	$ 153,493,000
FHLB advances maturity period	1 year	2 years
Federal Home Loan Bank Advances
Other borrowed funds disclosures
Borrowings outstanding	$ 325,000,000	$ 150,000,000
Total borrowing capacity available	$ 948,200,000	$ 608,800,000
Average interest rate of outstanding balances	1.41%	0.59%
Federal Reserve Bank Advances
Other borrowed funds disclosures
Borrowings outstanding	$ 0	$ 0
Available borrowing capacity	384,500,000	330,000,000
Federal Funds Purchased
Other borrowed funds disclosures
Federal Funds purchased outstanding	$ 0	$ 0

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

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Maturity period on variable rate advances made and reported by Federal Home Loan Bank (FHLBank), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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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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