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Loans and Allowance for Credit Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 22,874
Provision (reversal) - CECL	(2,929)
Charge-offs	0
Recoveries	13
Ending balance	19,958
Beginning balance		$ 16,677
Provision (reversal) - CECL	(2,929)	2,200
Charge-offs		0
Recoveries		7
Ending balance		18,884
Commercial loans | Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,530
Provision (reversal) - CECL	(880)
Charge-offs	0
Recoveries	4
Ending balance	1,654
Beginning balance		2,334
Provision (reversal) - CECL		446
Charge-offs		0
Recoveries		4
Ending balance		2,784
Commercial real estate loans | Commercial owner-occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,778
Provision (reversal) - CECL	(474)
Charge-offs	0
Recoveries	0
Ending balance	2,304
Beginning balance		2,462
Provision (reversal) - CECL		335
Charge-offs		0
Recoveries		0
Ending balance		2,797
Commercial real estate loans | Commercial investor-owned
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	12,682
Provision (reversal) - CECL	(1,826)
Charge-offs	0
Recoveries	0
Ending balance	10,856
Beginning balance		8,483
Provision (reversal) - CECL		742
Charge-offs		0
Recoveries		0
Ending balance		9,225
Commercial real estate loans | Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,557
Provision (reversal) - CECL	(254)
Charge-offs	0
Recoveries	9
Ending balance	1,312
Beginning balance		638
Provision (reversal) - CECL		86
Charge-offs		0
Recoveries		3
Ending balance		727
Residential loans | Home equity
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	738
Provision (reversal) - CECL	(218)
Charge-offs	0
Recoveries	0
Ending balance	520
Beginning balance		850
Provision (reversal) - CECL		132
Charge-offs		0
Recoveries		0
Ending balance		982
Residential loans | Other residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	998
Provision (reversal) - CECL	(241)
Charge-offs	0
Recoveries	0
Ending balance	757
Beginning balance		973
Provision (reversal) - CECL		125
Charge-offs		0
Recoveries		0
Ending balance		1,098
Consumer loans | Installment and other consumer loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	291
Provision (reversal) - CECL	(36)
Charge-offs	0
Recoveries	0
Ending balance	255
Beginning balance		284
Provision (reversal) - CECL		79
Charge-offs		0
Recoveries		0
Ending balance		363
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,300
Provision (reversal) - CECL	1,000
Charge-offs	0
Recoveries	0
Ending balance	$ 2,300
Beginning balance		653
Provision (reversal) - CECL		255
Charge-offs		0
Recoveries		0
Ending balance		$ 908

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- Definition

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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