LOANS AND ALLOWANCE FOR LOAN LOSSES - Rollforward for Purchased Loans (Details) - Purchased Loans - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance, January 1	$ 861,595	$ 1,069,191
Charge-offs	(1,803)	(3,411)
Additions due to acquisitions	2,053,744	0
Accretion	(11,918)	(11,308)
Transfers to purchased other real estate owned	(6,396)	(5,023)
Payments received	(330,226)	(210,470)
Ending balance	$ 2,588,832	$ 861,595

Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Charge-Offs

No definition available.

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- Definition

Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Payments Received

+ References

No definition available.

+ Details

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- Definition

Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Transfers to Other Real Estate Owned

+ References

No definition available.

+ Details

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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- Definition

Amount of accretion recognized for 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

+ Details

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- Definition

Amount of additions to 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

+ Details

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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.

+ Details

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