BORROWINGS Borrowings - - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Subordinated Debt	$ 170,550	$ 120,000
Debt, Weighted Average Interest Rate	5.28%	5.13%
Commitments outstanding to extend credit	$ 0	$ 0
Subordinated debt, original issue	$ 120,000
Subordinated Borrowing, Interest Rate	5.125%
Book value of FHLB collateral	$ 5,700,000
Private Placement [Member]
Debt Instrument [Line Items]
Subordinated Debt	$ 8,400
Debt, Weighted Average Interest Rate	7.40%
Subordinated Debt [Member]
Debt Instrument [Line Items]
Subordinated Debt	$ 49,500
Debt Instrument Maturity Period	30 years
DebtInstrumentMinimumCallablePeriod	5 years
Private Placement [Member]
Debt Instrument [Line Items]
DebtInstrumentMinimumCallablePeriod	5 years

Debt Instrument Maturity Period

No definition available.

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- Definition

Represents the period at par after which the debt can be called.

+ References

No definition available.

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- Definition

Subordinated debt amount of original issue, excluding issue costs

+ References

No definition available.

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- Definition

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

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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- Definition

Stated interest rate of the subordinated debt.

+ References

No definition available.

+ Details

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

+ References

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