Loans, net and allowance for loan losses - Changes in Allowance for Loan Losses Account by Major Classification of Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Allowance for loan losses:
Beginning Balance	$ 26,739	$ 26,957	$ 27,344	$ 22,677
Charge-offs	(466)	(1,542)	(851)	(2,957)
Recoveries	20	119	200	514
Provisions (credits)	400	1,050		6,350
Ending balance	26,693	26,584	26,693	26,584
Increase (decrease) in charge offs due to a partial write down of a non-accrual commercial relationship			1,500
Commercial
Allowance for loan losses:
Beginning Balance	8,520	8,487	8,734	6,888
Charge-offs	(446)	(1,354)	(461)	(2,339)
Recoveries	4	51	83	349
Provisions (credits)	(164)	1,271	(442)	3,557
Ending balance	7,914	8,455	7,914	8,455
Real estate Commercial
Allowance for loan losses:
Beginning Balance	14,281	13,855	14,559	11,496
Charge-offs	(12)	(66)	(252)	(113)
Recoveries	1	14	67	14
Provisions (credits)	519	(5)	415	2,401
Ending balance	14,789	13,798	14,789	13,798
Real estate Residential
Allowance for loan losses:
Beginning Balance	3,069	3,567	3,129	3,226
Charge-offs		(71)	(24)	(206)
Recoveries		9	2	22
Provisions (credits)	92	(159)	54	304
Ending balance	3,161	3,346	3,161	3,346
Consumer
Allowance for loan losses:
Beginning Balance	869	1,048	922	1,067
Charge-offs	(8)	(51)	(114)	(299)
Recoveries	15	45	48	129
Provisions (credits)	(47)	(57)	(27)	88
Ending balance	$ 829	$ 985	$ 829	$ 985

The amount of increase (decrease) in charge offs due to a partial write down of a non-accrual commercial relationship.

No definition available.

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of expense related to estimated loss from loan and lease transactions.

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