SECURITIES (Textual) (Details)	9 Months Ended
Sep. 30, 2017 USD ($) security	Sep. 30, 2016 USD ($) security	Dec. 31, 2016 security
Trading Securities [Abstract]
Trading Securities, Sale Proceeds	$ 0	$ 1,682,000
Trading Securities, Realized Gain (Loss)	0	156,000
Trading Securities, OTTI (Recovery) Charges	$ 0	$ 0
Trading Securities, Number of Securities on Nonaccrual Status \| security	0	0
Trading Securities, Unrealized Holding Gain	$ 389,000
Available-for-sale Securities [Abstract]
Available-for-sale Securities, Number of Securities in Unrealized Loss Position \| security	221		243
Available-for-sale Securities, Sale Proceeds	$ 35,600,000	$ 233,300,000
Available-for-sale Securities, Gross Realized Gain (Loss)	230,000	374,000
Available-for-sale Securities, OTTI Charges	$ 0	$ 0
Available-for-sale Securities, Number of Securities in Nonaccrual Status \| security	0	0
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities, Number of Securities in Unrealized Loss Position \| security	31		73
Held-to-maturity Securities, Number of Securities Sold \| security	0	0
Held-to-maturity Securities, Sale Proceeds	$ 0
Held-to-maturity Securities, OTTI Charges	$ 0	$ 0
Held-to-maturity Securities, Number of Securities in Nonaccrual Status \| security	0	0

Available-for-sale Securities, Number of Securities in Nonaccrual Status

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Held-to-maturity Securities, Number of Securities in Nonaccrual Status

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Held-to-maturity Securities, Realized Gain (Loss), Number of Securities Sold

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- Definition

Other than Temporary Impairment Losses (Recoveries) Investments, Portion Recognized in Earnings, Trading Securities

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Trading Securities, Number of Securities in Nonaccrual Status

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This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563

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The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period.

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Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27290-111563

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Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired.

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The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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The amount of other than temporary impairment losses on investments in debt securities categorized as Held-to-maturity which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) of investments in debt securities due to credit losses and other than temporary impairments due to other than credit losses when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

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- Definition

Amount of cash inflow (outflow) from sales and purchases of trading securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26853-111562

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The cash inflow associated with the sale of securities that had been designated as held-to-maturity. Excludes proceeds from maturities, prepayments and calls by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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Amount of gain (loss) realized from securities classified as trading.

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Amount of unrealized holding gain before loss recognized in the income statement for investments in trading securities.

+ 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 210.5-03.7(c))
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