SECURITIES AVAILABLE FOR SALE - Securities Pledged for Collateral (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Carrying Amount
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged for deposits	$ 195,921	$ 92,380
Securities pledged for repurchase agreements	98,407	28,206
Securities pledged for other borrowings	213,379	278,067
Total securities pledged	507,707	398,653
Estimated Fair Value
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged for deposits	194,681	92,149
Securities pledged for repurchase agreements	98,050	28,130
Securities pledged for other borrowings	212,089	277,261
Total securities pledged	$ 504,820	$ 397,540

Pledged Assets Separately Reported, Securities Pledged for Deposits, at Fair Value

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- Definition

Pledged Assets Separately Reported, Securities Pledged for Federal Home Loan Bank and Federal Reserve Bank, at Fair Value

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No definition available.

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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.

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No definition available.

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- Definition

The sum of the fair values, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of related debt obligations, primarily secured borrowings and repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

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- Definition

The fair value, as of the date of each statement of financial position presented, of securities which are owned but transferred to serve as collateral for the payment of repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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