BORROWINGS - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Amount
Secured Debt	$ 0	$ 434,982
FHLB long-term advances	0	19,971
Subordinated debt	313,134	321,384
Unamortized debt issuance costs	(2,480)	(2,770)
Finance Lease, Liability	1,801	1,860
Capital loan with municipality	775	775
Total long-term debt	$ 313,230	$ 776,202
Average Rate
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate	0.00%	0.35%
Federal Home Loan Bank	0.00%	1.43%
Debt, Weighted Average Interest Rate	4.85%	4.86%
Lessee, Finance Lease, Discount Rate	3.81%	3.81%
Weighted average rate on other long-term debt	0.00%	0.00%
Total long-term debt	4.87%	2.25%

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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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Present value of lessee's discounted obligation for lease payments from finance lease.

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Discount rate used by lessee to determine present value of finance lease payments.

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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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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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Amount of long-term debt classified as other.

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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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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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