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- Definition

Amount, before allowance for credit loss, of accrued interest on financing receivable.

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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- Definition

Amount, after allowance for credit loss and unamortized deferred fee, premium, and discount, of financing receivable covered under loss sharing agreement and financing receivable not covered under loss sharing agreement.

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Amount, before allowance for credit loss, of financing receivable.

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LOANS (Loans receivable) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Loans and Leases [Line Items]
Held to maturity	$ 9,854,907		$ 10,023,051
Allowance for credit losses	(117,533)	$ (120,726)	(131,606)	$ (103,377)	$ (119,937)	$ (70,395)
Loans receivable, net	9,737,374		9,891,445
Accrued interest receivable	37,400		42,400
Commercial and industrial \| Commercial and industrial
Loans and Leases [Line Items]
Held to maturity	2,538,369		2,534,799
Allowance for credit losses	(27,908)	(31,332)	(38,818)	(34,581)	(32,518)	(34,207)
Commercial and industrial \| Paycheck Protection Program ("PPP")
Loans and Leases [Line Items]
Held to maturity	409,247		957,785
Allowance for credit losses	0	0	0	0	0	0
Commercial and industrial \| Owner occupied commercial real estate
Loans and Leases [Line Items]
Held to maturity	2,135,227		1,776,406
Allowance for credit losses	(19,128)	(19,990)	(20,001)	(11,229)	(23,402)	(7,921)
Commercial and industrial \| Non-owner occupied commercial real estate
Loans and Leases [Line Items]
Held to maturity	2,020,487		1,921,481
Allowance for credit losses	(22,115)	(22,828)	(20,873)	(12,127)	(10,161)	(7,584)
Commercial and industrial \| Real estate construction
Loans and Leases [Line Items]
Held to maturity	814,001		863,220
Allowance for credit losses	(23,698)	(19,580)	(20,080)	(20,787)	(28,667)	(8,677)
Agricultural and agricultural real estate
Loans and Leases [Line Items]
Held to maturity	684,670		714,526
Allowance for credit losses	(6,326)	(7,160)	(7,129)	(5,342)	(5,701)	(5,680)
Residential real estate
Loans and Leases [Line Items]
Held to maturity	840,356		840,442
Allowance for credit losses	(9,238)	(9,741)	(11,935)	(9,671)	(9,304)	(1,504)
Consumer
Loans and Leases [Line Items]
Held to maturity	412,550		414,392
Allowance for credit losses	$ (9,120)	$ (10,095)	$ (12,770)	$ (9,640)	$ (10,184)	$ (4,822)