BORROWINGS Borrowings - - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Dec. 31, 2017
FHLB short-term borrowings	$ 1,170,800	$ 742,300
Line of Credit Facility, Maximum Borrowing Capacity	30,000
Commitments outstanding to extend credit	0	0
Short-term Debt	1,294,252	814,565
Long-term Debt	570,037	119,654
Subordinated debt	$ 120,000
Subordinated Borrowing, Interest Rate	5.125%
Subordinated debt	$ 177,887	120,000
Advances from Federal Home Loan Banks	$ 400,046	$ 241
Federal Home Loan Bank	2.09%	1.09%
Subordinated Debt [Member]
Subordinated debt	$ 49,500
Private Placement [Member]
Subordinated debt	$ 8,400
Debt Instrument, Interest Rate, Effective Percentage	6.94%
Private Placement [Member]
DebtInstrumentMinimumCallablePeriod	5 years
Subordinated Debt [Member]
Debt Instrument Maturity Period	30 years
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

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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- Definition

Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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- Definition

Stated interest rate of the subordinated debt.

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No definition available.

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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.

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