v3.21.2

FAIR VALUE MEASUREMENTS - Valuation assumptions (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Reserves related to impaired loans	$ 1,200		$ 1,200		$ 1,100
Provision for credit losses - loans	(417)	$ 1,548	(13)	$ 6,979
Fair Value Measurement Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Provision for credit losses - loans			2,900
Impaired loans	$ 10,200		$ 10,200		$ 3,100
Fair Value Measurement Level 3 | Prepayment Rate | Minimum | Available for Sale
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Alternative investment measurement input	0.30		0.30		0.30
Fair Value Measurement Level 3 | Prepayment Rate | Minimum | Mortgage Servicing Rights
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Alternative investment measurement input	0.20		0.20
Fair Value Measurement Level 3 | Prepayment Rate | Maximum | Available for Sale
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Alternative investment measurement input	0.35		0.35		0.35
Fair Value Measurement Level 3 | Prepayment Rate | Maximum | Mortgage Servicing Rights
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Alternative investment measurement input	0.30		0.30
Fair Value Measurement Level 3 | Discount Rate | Minimum | Available for Sale
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Alternative investment measurement input	0.0670		0.0670		0.0670
Fair Value Measurement Level 3 | Discount Rate | Minimum | Mortgage Servicing Rights
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Alternative investment measurement input	0.0021		0.0021
Fair Value Measurement Level 3 | Discount Rate | Maximum | Available for Sale
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Alternative investment measurement input	0.10		0.10		0.10
Fair Value Measurement Level 3 | Discount Rate | Maximum | Mortgage Servicing Rights
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Alternative investment measurement input	0.10		0.10

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