BORROWINGS - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Amount
Subordinated Debt	$ 170,550	$ 120,000
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(1,185)	(1,362)
FHLB long-term advances	400,599	241
Other Long-term Debt	775	775
Total long-term debt	$ 570,739	$ 119,654
Average Rate [Abstract]
Debt, Weighted Average Interest Rate	5.28%	5.13%
Federal Home Loan Bank	2.08%	1.09%
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	0.00%	0.00%
Long-term Debt, Weighted Average Interest Rate, at Point in Time	3.04%	5.14%
Maturities of Long-term Debt [Abstract]
2019	$ 157,914
2020	104,274
2021	19,007
2022	49,404
2023	0
Thereafter	$ 240,140

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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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Amount of unamortized debt discount (premium) and debt issuance costs.

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Weighted average interest rate of debt outstanding.

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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, 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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Amount of long-term debt classified as other.

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