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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of other-than-temporary impairment (OTTI) applied to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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FAIR VALUE - Additional Information (Details) - USD ($)	12 Months Ended
FAIR VALUE - Additional Information (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	3.40%
Mortgage servicing rights	$ 3,100,000
Mortgage servicing rights, impairment	715,000
Amortized cost	2,400,000
Valuation reserve	$ 0	$ 715,000	$ 0
Weighted average maturity of residential mortgages	20 years
Prepayment Speed used in unobservable assumptions	249	204
Discount rate used to estimate fair value	9.50%	9.40%
Gross loans	$ 4,291,105,000	$ 4,657,183,000
Valuation allowance after adoption of ASC 326	67,773,000	61,408,000	50,652,000	$ 48,453,000
Recoveries	2,221,000	$ 1,239,000	$ 874,000
Minimum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Amount of variance	$ 100,000
Minimum \| Commercial Real Estates \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	0.00%
Minimum \| Inventory Finished Goods \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	35.00%
Minimum \| Finished Goods \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	30.00%
Minimum \| Inventory Work In Process \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	50.00%
Minimum \| Equipment \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	30.00%
Minimum \| Marketable Securities \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	10.00%
Maximum \| Commercial Real Estates \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	50.00%
Maximum \| Inventory Finished Goods \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	65.00%
Maximum \| Finished Goods \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	60.00%
Maximum \| Inventory Work In Process \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	100.00%
Maximum \| Equipment \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	70.00%
Maximum \| Marketable Securities \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	30.00%
Municipal Notes \| Minimum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of variance	5.00%
Municipal Notes \| Maximum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of variance	5.00%
US Government Agencies Short-term Debt Securities \| Minimum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of variance	(3.00%)
U.S. Treasury securities \| Minimum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of variance	(1.00%)
U.S. Treasury securities \| Maximum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of variance	(1.00%)