Loans, Loans Modified in a Troubled Debt Restructuring (Details) $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) loan	Mar. 31, 2020 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	25	30
Recorded Investment(a)	$ 5,999	$ 4,899
Unpaid Principal Balance(b)	$ 6,025	$ 6,175
Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	1
Recorded Investment(a)	$ 0	$ 48
Unpaid Principal Balance(b)	$ 0	$ 48
Commercial real estate — owner occupied
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	1
Recorded Investment(a)	$ 0	$ 290
Unpaid Principal Balance(b)	$ 0	$ 321
Commercial real estate — investor
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	4	1
Recorded Investment(a)	$ 1,693	$ 570
Unpaid Principal Balance(b)	$ 1,693	$ 1,740
Real estate construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	1
Recorded Investment(a)	$ 0	$ 122
Unpaid Principal Balance(b)	$ 0	$ 122
Residential mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	20	18
Recorded Investment(a)	$ 3,876	$ 3,592
Unpaid Principal Balance(b)	$ 3,902	$ 3,668
Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	1	8
Recorded Investment(a)	$ 430	$ 277
Unpaid Principal Balance(b)	$ 430	$ 277

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

+ 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=123577603&loc=SL6953676-111524

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

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

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