BORROWINGS Borrowings - - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Carrying Value of Securities Sold under Repurchase Agreements and Deposits Received for Securities Loaned	$ 107,000	$ 90,200
Federal Funds Purchased	47,000	165,200
FHLB short-term borrowings	0	1,151,000
Line of Credit Facility, Maximum Borrowing Capacity	30,000
Commitments outstanding to extend credit	0	0
Long-term Debt	1,285,767	414,376
Secured Debt	$ 811,772	0
Long Term Debt Percentage in Basis Points	35
Convertible Subordinated Debt	$ 150,000
Subordinated Borrowing, Interest Rate	5.125%
Debt Instrument, Basis Spread on Variable Rate	50900.00%
Subordinated debt	$ 120,000
Subordinated debt	$ 321,176	$ 170,967
Debt, Weighted Average Interest Rate	4.88%	4.97%
Advances from Federal Home Loan Banks	$ 153,117	$ 242,428
Federal Home Loan Bank	1.75%	1.94%
Weighted average rate on other long-term debt	0.00%	0.00%
Private Placement [Member]
Subordinated debt	$ 8,400
Debt, Weighted Average Interest Rate	6.00%
Long-term Debt [Member]
Subordinated Borrowing, Interest Rate	5.25%
Private Placement [Member]
DebtInstrumentMinimumCallablePeriod	5 years
Subordinated Debt [Member]
Subordinated debt	$ 49,500
Debt Instrument Maturity Period	30 years
DebtInstrumentMinimumCallablePeriod	5 years

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- Definition

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

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No definition available.

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- Definition

Long Term Debt Percentage shown in basis points

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Subordinated debt amount of original issue, excluding issue costs

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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.

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Carrying value of securities sold under agreements to repurchase and deposits received for securities loaned.

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Including the current and noncurrent portions, the carrying value of convertible subordinated debt, as of the balance sheet date, initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. This form of debt can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder, and 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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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Weighted average interest rate of debt outstanding.

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No definition available.

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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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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.

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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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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Stated interest rate of the subordinated debt.

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No definition available.

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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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