LOANS - Rollforward of Accretable Discounts of Purchased Loans (Details) - Purchased Loans - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance, January 1	$ 1,069,191	$ 909,083
Additions due to acquisitions	0	402,942
Ending balance	917,126	1,129,381
Discount Accretion
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance, January 1	30,624	33,848
Additions due to acquisitions	0	9,991
Accretion	(9,023)	(12,926)
Accretable discounts removed due to charge-offs	(15)	(161)
Transfers between non-accretable and accretable discounts, net	923	2,544
Ending balance	$ 22,509	$ 33,296

Accretable discounts removed due to charge-offs.

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- Definition

Accretion of discount on purchased non-covered loans.

+ References

No definition available.

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- Definition

Certain loans acquired in transfer accounted for as debt securities non accretable and accretable discounts net.

+ References

No definition available.

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- Definition

Increases in the aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan due to the acquisition of similar loans accounted for as debt securities during the period. This relates to loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538

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- Definition

Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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