SECURITIES - Other-Than-Temporary Impairment and Other Disclosures (Details) $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($) item	Dec. 31, 2016 USD ($)
Other-Than-Temporary-Impairment
Number of general segments segregated in investment securities portfolio \| item	2
Number of security in the portfolio \| item	981
Number of portfolio security in unrealized loss position \| item	202
Market value of securities in unrealized loss position	$ 486,799	$ 517,702
Unrealized losses of collateralized mortgage obligation securities	8,268	8,904
State and municipal
Other-Than-Temporary-Impairment
Market value of securities in unrealized loss position	73,729	95,822
Unrealized losses of collateralized mortgage obligation securities	2,377	2,848
Mortgage-backed securities
Other-Than-Temporary-Impairment
Unrealized losses of collateralized mortgage obligation securities	4,439
Collateralized mortgage obligations (Government Sponsored Entity)
Other-Than-Temporary-Impairment
Market value of securities in unrealized loss position	102,291	86,212
Unrealized losses of collateralized mortgage obligation securities	1,452	$ 1,427
Other than temporary impairment on available for sale securities	$ 0

Represents the number of securities in the entity's security portfolio.

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- Definition

Represents the number of general segments into which the investment securities portfolio is segregated for other-than-temporary-impairment losses evaluation.

+ References

No definition available.

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- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27290-111563

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27290-111563

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- Definition

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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- References

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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.

+ References

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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