Loans and Allowance for Credit Losses - Loans modified in troubled debt restructurings (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021 loan	Jun. 30, 2020 loan	Jun. 30, 2021 USD ($) contract	Jun. 30, 2020 USD ($) contract
Loans and Leases Receivable Disclosure [Line Items]
Number of loans - restructured accruing	1	1	5	10
Number of loans - restructured nonaccruing \| contract			2	3
Number of TDR loans \| contract			7	13
Restructured accruing			$ 10,245	$ 12,272
Restructured nonaccruing			6,342	8,050
Troubled debt restructured			16,587	20,322
Specific allowance			3,072	1,552
Restructured and subsequently defaulted			6,342	8,050
Commercial
Loans and Leases Receivable Disclosure [Line Items]
Restructured accruing			1,096	1,420
Restructured nonaccruing			0	138
Troubled debt restructured			1,096	1,558
Specific allowance			364	257
Restructured and subsequently defaulted			0	138
Income producing - commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Restructured accruing			9,149	10,016
Restructured nonaccruing			6,342	5,542
Troubled debt restructured			15,491	15,558
Specific allowance			2,708	1,295
Restructured and subsequently defaulted			6,342	5,542
Owner occupied - commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Restructured accruing			0	836
Restructured nonaccruing			0	2,370
Troubled debt restructured			0	3,206
Specific allowance			0	0
Restructured and subsequently defaulted			0	2,370
Construction Commercial Real Estate
Loans and Leases Receivable Disclosure [Line Items]
Restructured accruing			0	0
Restructured nonaccruing			0	0
Troubled debt restructured			0	0
Specific allowance			0	0
Restructured and subsequently defaulted			$ 0	$ 0

Number of financing receivables outstanding that have been modified by troubled debt restructurings.

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings accruing.

+ References

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings nonaccruing.

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Number of accruing financing receivables that have been modified by troubled debt restructurings.

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Number of nonaccruing financing receivables that have been modified by troubled debt restructurings.

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Amount of credit loss expense (reversal of expense) for financing receivable from change in methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 11
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919244-210447

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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- Definition

Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953682-111524

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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