FAIR VALUE (Schedule of Financial Instruments) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financial Assets:
Securities available for sale	$ 596,929	$ 390,755
FHLB and FRB stock	18,433	24,068
Loans held for sale, at fair value	13,785	2,881
Loans held for sale, at lower of cost or fair value	14,455	14,667
Accrued interest receivable	22,192	10,494
Financial Liabilities:
Short-term borrowings	15,000	128,100
Federal home loan bank advances	105,000	105,000
Paycheck Protection Program Liquidity Facility	183,790
Carrying Value [Member]
Financial Assets:
Cash and cash equivalents	679,365	208,185
Securities available for sale	596,929	390,755
CRA investment fund	15,159	10,836
FHLB and FRB stock	18,433	24,068
Loans held for sale, at fair value	13,785	2,881
Loans held for sale, at lower of cost or fair value	14,455	14,667
Loans, net of allowance for loan and lease losses	4,364,506	4,350,461
Accrued interest receivable	22,192	10,494
Financial Liabilities:
Deposits	4,859,150	4,243,511
Short-term borrowings	15,000	128,100
Federal home loan bank advances	105,000	105,000
Paycheck Protection Program Liquidity Facility	183,790
Subordinated debt	83,585	83,417
Accrued interest payable	3,017	2,357
Carrying Value [Member] \| Designated as Hedging Instrument [Member]
Financial Assets:
Derivatives		121
Financial Liabilities:
Derivatives	11,001	3,788
Carrying Value [Member] \| Not Designated as Hedging Instrument [Member]
Financial Assets:
Derivatives	92,798	32,381
Financial Liabilities:
Derivatives	92,798	32,381
Fair value [Member]
Financial Assets:
Cash and cash equivalents	679,365	208,185
Securities available for sale	596,929	390,755
CRA investment fund	15,159	10,836
Loans held for sale, at fair value	13,785	2,881
Loans held for sale, at lower of cost or fair value	14,943	15,126
Loans, net of allowance for loan and lease losses	4,493,612	4,268,481
Accrued interest receivable	22,192	10,494
Financial Liabilities:
Deposits	4,868,927	4,247,427
Short-term borrowings	15,000	128,100
Federal home loan bank advances	109,908	108,354
Paycheck Protection Program Liquidity Facility	183,790
Subordinated debt	84,215	86,536
Accrued interest payable	3,017	2,357
Fair value [Member] \| Quoted Prices in Active Market For Identical Assets (Level 1) [Member]
Financial Assets:
Cash and cash equivalents	679,365	208,185
CRA investment fund	15,159	10,836
Financial Liabilities:
Deposits	4,205,922	3,528,609
Accrued interest payable	210	392
Fair value [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Financial Assets:
Securities available for sale	596,929	390,755
Loans held for sale, at fair value	13,785	2,881
Loans held for sale, at lower of cost or fair value	14,943	15,126
Accrued interest receivable	1,807	1,361
Financial Liabilities:
Deposits	663,005	718,818
Short-term borrowings	15,000	128,100
Federal home loan bank advances	109,908	108,354
Paycheck Protection Program Liquidity Facility	183,790
Accrued interest payable	1,586	1,910
Fair value [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Financial Assets:
Loans, net of allowance for loan and lease losses	4,493,612	4,268,481
Accrued interest receivable	20,385	9,133
Financial Liabilities:
Subordinated debt	84,215	86,536
Accrued interest payable	1,221	55
Fair value [Member] \| Designated as Hedging Instrument [Member]
Financial Assets:
Derivatives		121
Financial Liabilities:
Derivatives	11,001	3,788
Fair value [Member] \| Designated as Hedging Instrument [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Financial Assets:
Derivatives		121
Financial Liabilities:
Derivatives	11,001	3,788
Fair value [Member] \| Not Designated as Hedging Instrument [Member]
Financial Assets:
Derivatives	92,798	32,381
Financial Liabilities:
Derivatives	92,798	32,381
Fair value [Member] \| Not Designated as Hedging Instrument [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Financial Assets:
Derivatives	92,798	32,381
Financial Liabilities:
Derivatives	$ 92,798	$ 32,381

Loans And Leases Receivable, Held At Cost Or Fair Value.

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Paycheck protection program liquidity facility.

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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 investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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