Represents the note balance amount of loans, considered impaired, at the time of acquisition.

No definition available.

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- Definition

Represents the carrying amount of loans, not considered impaired, at the time of acquisition.

+ References

No definition available.

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- Definition

Represents the reasonable period of a borrower's sustained repayment performance for consideration of returning the loan to performing status.

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for 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)(1)
-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

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-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

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 4
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- Definition

The fair value of collateral received that was taken through foreclosure due to default by the original transferor in lieu of collection of the secured receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4437-111522

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LOANS - Narrative (Details) $ in Thousands	3 Months Ended		12 Months Ended
LOANS - Narrative (Details) $ in Thousands	Mar. 31, 2018 USD ($) contract	Mar. 31, 2017 contract	Dec. 31, 2016 USD ($)	Dec. 31, 2017 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 8,376,417			$ 8,299,338
Borrower's sustained repayment performance period	6 months
Modifications that subsequently defaulted, number of contracts \| contract	0	2
Residential Mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 2,181,807			2,102,807
Residential Mortgages \| Mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Process of foreclosure	7,200		$ 4,900
Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	2,093,739			2,187,140
Acquired Credit Impaired	93,645			97,344
Certain loans acquired in transfer not accounted for as debt securities, note balance, net	202,800			208,700
Financing receivable not considered impaired at time of acquisition	2,000,000			2,100,000
Acquired Loans \| Residential Mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	275,094			289,606
Acquired Credit Impaired	6,903			6,974
Acquired Loans \| Residential Mortgages \| Mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 275,094			$ 289,606