LOANS (Loans Held to Maturity) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable held to maturity	$ 11,428,352	$ 9,954,572
Allowance for credit losses	(109,483)	(110,088)
Loans receivable, net	11,318,869	9,844,484
Commercial and industrial \| Commercial and industrial
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable held to maturity	3,464,414	2,645,085
Allowance for credit losses	(29,071)	(27,738)
Commercial and industrial \| Paycheck Protection Program ("PPP")
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable held to maturity	11,025	199,883
Allowance for credit losses	0	0
Commercial and industrial \| Owner occupied commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable held to maturity	2,265,307	2,240,334
Allowance for credit losses	(13,948)	(19,214)
Commercial and industrial \| Non-owner occupied commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable held to maturity	2,330,940	2,010,591
Allowance for credit losses	(16,539)	(17,908)
Commercial and industrial \| Real estate construction
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable held to maturity	1,076,082	856,119
Allowance for credit losses	(29,998)	(22,538)
Agricultural and agricultural real estate
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable held to maturity	920,510	753,753
Allowance for credit losses	(2,634)	(5,213)
Residential real estate
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable held to maturity	853,361	829,283
Allowance for credit losses	(7,711)	(8,427)
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable held to maturity	506,713	419,524
Allowance for credit losses	$ (9,582)	$ (9,050)

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=6378536&loc=d3e10095-111533

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

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