Loans and allowance for credit losses - Amortized Cost and Related Allowance of Non-accrual Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
Non-accrual with no related allowance	$ 24,386	$ 32,661
Non-accrual with related allowance	11,182	18,099
Related allowance	555	2,550
Year to date Interest Income	3,400	816
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Non-accrual with no related allowance	1,085	13,960
Non-accrual with related allowance	435	2,045
Related allowance	6	383
Year to date Interest Income	1,371	325
Construction
Financing Receivable, Past Due [Line Items]
Non-accrual with no related allowance	2,882	3,061
Non-accrual with related allowance	740	992
Related allowance	99	131
Year to date Interest Income	156	69
Residential real estate \| 1-to-4 family mortgage
Financing Receivable, Past Due [Line Items]
Non-accrual with no related allowance	378	3,048
Non-accrual with related allowance	4,215	2,875
Related allowance	60	84
Year to date Interest Income	314	22
Residential real estate \| Residential line of credit
Financing Receivable, Past Due [Line Items]
Non-accrual with no related allowance	797	854
Non-accrual with related allowance	939	903
Related allowance	11	31
Year to date Interest Income	289	72
Residential real estate \| Multi-family mortgage
Financing Receivable, Past Due [Line Items]
Non-accrual with no related allowance	0
Non-accrual with related allowance	49
Related allowance	2
Year to date Interest Income	3
Commercial real estate \| Owner occupied
Financing Receivable, Past Due [Line Items]
Non-accrual with no related allowance	5,346	7,172
Non-accrual with related allowance	1,364	776
Related allowance	206	63
Year to date Interest Income	536	89
Commercial real estate \| Non-owner occupied
Financing Receivable, Past Due [Line Items]
Non-accrual with no related allowance	13,898	4,566
Non-accrual with related allowance	186	7,905
Related allowance	7	1,711
Year to date Interest Income	486	215
Consumer and other
Financing Receivable, Past Due [Line Items]
Non-accrual with no related allowance	0	0
Non-accrual with related allowance	3,254	2,603
Related allowance	164	147
Year to date Interest Income	$ 245	$ 24

Financing Receivable, Allowance For Credit Losses, Nonaccrual

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- Definition

Financing Receivable, Nonaccrual, Related Allowance

+ References

No definition available.

+ Details

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- Definition

Amount of interest income on financing receivable on nonaccrual status.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

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- Definition

Amount of financing receivable on nonaccrual status with no allowance for credit loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

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- Definition

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+ References

No definition available.

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