Loans and Allowance for Loan Losses - Changes in allowance (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Changes in the allowance
Beginning Balance	$ 34,246	$ 23,924
Provision for loan losses		2,500
Loan charge-offs	(784)	(99)
Loan recoveries	296	694
Ending Balance	33,758	27,019
Unallocated
Changes in the allowance
Beginning Balance	1,378	2,192
Provision for loan losses	(555)	(359)
Ending Balance	823	1,833
Commercial
Changes in the allowance
Beginning Balance	24,968	19,261
Provision for loan losses	533	1,689
Loan charge-offs	(740)	(32)
Loan recoveries	173	593
Ending Balance	24,934	21,511
Commercial \| Commercial and industrial
Changes in the allowance
Beginning Balance	10,205	12,270
Provision for loan losses	316	70
Loan charge-offs	(204)	(32)
Loan recoveries	170	593
Ending Balance	10,487	12,901
Commercial \| Real estate construction
Changes in the allowance
Beginning Balance	658	303
Provision for loan losses	(60)	31
Ending Balance	598	334
Commercial \| Commercial real estate
Changes in the allowance
Beginning Balance	14,105	6,688
Provision for loan losses	277	1,588
Loan charge-offs	(536)
Loan recoveries	3
Ending Balance	13,849	8,276
Consumer
Changes in the allowance
Beginning Balance	7,900	2,471
Provision for loan losses	22	1,170
Loan charge-offs	(44)	(67)
Loan recoveries	123	101
Ending Balance	8,001	3,675
Consumer \| Residential \| Real estate first mortgage
Changes in the allowance
Beginning Balance	5,774	1,448
Provision for loan losses	273	761
Ending Balance	6,047	2,209
Consumer \| Residential \| Real estate junior lien
Changes in the allowance
Beginning Balance	1,373	671
Provision for loan losses	(168)	317
Loan recoveries	83	37
Ending Balance	1,288	1,025
Consumer \| Other revolving and installment
Changes in the allowance
Beginning Balance	753	352
Provision for loan losses	(83)	92
Loan charge-offs	(44)	(67)
Loan recoveries	40	64
Ending Balance	$ 666	$ 441

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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- Definition

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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No definition available.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 310
-SubTopic 10
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