FAIR VALUE - CARRYING AMOUNTS AND FV OF FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Assets:
Available-for-sale debt securities	$ 622,145		$ 495,126
Held-to-maturity debt securities	32,978		44,764
Equity securities with readily determinable fair value	189		2,620
Mortgage loans held for sale, at fair value	8,491	$ 13,302	29,393	$ 32,401	$ 63,636	$ 46,867
Consumer loans held for sale, at fair value	17,459	11,709	19,747	13,020	3,970	3,298
Consumer loans held for sale, at the lower of cost or fair value	13,777	$ 3,026	2,937	$ 11,412	$ 11,701	$ 1,478
Carrying Value
Assets:
Cash and cash equivalents	795,143		756,971
Available-for-sale debt securities	622,145		495,126
Held-to-maturity debt securities	32,962		44,299
Equity securities with readily determinable fair value	189		2,620
Mortgage loans held for sale, at fair value	8,491		29,393
Consumer loans held for sale, at fair value	17,459		19,747
Consumer loans held for sale, at the lower of cost or fair value	13,777		2,937
Loans, net	4,297,784		4,431,985
Federal Home Loan Bank stock	10,311		10,311
Accrued interest receivable	9,872		9,877
Mortgage servicing rights	9,407		9,196
Rate lock loan commitments	220		1,404
Mandatory forward contracts	359		66
Interest rate swap agreements	4,501		5,786
Liabilities:
Securities sold under agreements to repurchase and other short-term borrowings	303,315		290,967
Federal Home Loan Bank advances	20,000		25,000
Accrued interest payable	162		159
Interest rate swap agreements	4,501		5,786
Carrying Value | Non Interest Bearing Deposits
Liabilities:
Deposit liabilities, fair value	2,094,436		1,990,781
Carrying Value | Transaction deposits
Liabilities:
Deposit liabilities, fair value	2,499,250		2,553,423
Carrying Value | Time deposits
Liabilities:
Deposit liabilities, fair value	233,843		296,214
Total Fair Value
Assets:
Cash and cash equivalents	795,143		756,971
Available-for-sale debt securities	622,145		495,126
Held-to-maturity debt securities	32,978		44,764
Equity securities with readily determinable fair value	189		2,620
Mortgage loans held for sale, at fair value	8,491		29,393
Consumer loans held for sale, at fair value	17,459		19,747
Consumer loans held for sale, at the lower of cost or fair value	13,777		2,937
Loans, net	4,165,381		4,445,244
Accrued interest receivable	9,872		9,877
Mortgage servicing rights	16,568		11,540
Rate lock loan commitments	220		1,404
Mandatory forward contracts	359		66
Interest rate swap agreements	4,501		5,786
Liabilities:
Securities sold under agreements to repurchase and other short-term borrowings	303,315		290,967
Federal Home Loan Bank advances	21,766		25,000
Accrued interest payable	162		159
Interest rate swap agreements	4,501		5,786
Total Fair Value | Non Interest Bearing Deposits
Liabilities:
Deposit liabilities, fair value	2,094,436		1,990,781
Total Fair Value | Transaction deposits
Liabilities:
Deposit liabilities, fair value	2,499,250		2,553,423
Total Fair Value | Time deposits
Liabilities:
Deposit liabilities, fair value	230,849		298,236
Total Fair Value | Fair Value, Inputs, Level 1
Assets:
Cash and cash equivalents	795,143		756,971
Available-for-sale debt securities	230,771		70,112
Equity securities with readily determinable fair value			2,450
Total Fair Value | Fair Value, Inputs, Level 2
Assets:
Available-for-sale debt securities	385,072		418,436
Held-to-maturity debt securities	32,978		44,764
Equity securities with readily determinable fair value	189		170
Mortgage loans held for sale, at fair value	8,491		29,393
Accrued interest receivable	9,872		9,877
Mortgage servicing rights	16,568		11,540
Rate lock loan commitments	220		1,404
Mandatory forward contracts	359		66
Interest rate swap agreements	4,501		5,786
Liabilities:
Securities sold under agreements to repurchase and other short-term borrowings	303,315		290,967
Federal Home Loan Bank advances	21,766		25,000
Accrued interest payable	162		159
Interest rate swap agreements	4,501		5,786
Total Fair Value | Fair Value, Inputs, Level 2 | Non Interest Bearing Deposits
Liabilities:
Deposit liabilities, fair value	2,094,436		1,990,781
Total Fair Value | Fair Value, Inputs, Level 2 | Transaction deposits
Liabilities:
Deposit liabilities, fair value	2,499,250		2,553,423
Total Fair Value | Fair Value, Inputs, Level 2 | Time deposits
Liabilities:
Deposit liabilities, fair value	230,849		298,236
Total Fair Value | Fair Value, Inputs, Level 3
Assets:
Available-for-sale debt securities	6,302		6,578
Consumer loans held for sale, at fair value	17,459		19,747
Consumer loans held for sale, at the lower of cost or fair value	13,777		2,937
Loans, net	$ 4,165,381		$ 4,445,244