Allowance for Loan and Lease Losses and Reserve for Unfunded Commitments - Summary of TDR's by Loan Category (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021 USD ($) Loan	Dec. 31, 2020 USD ($) Loan
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	28	30
Pre-Modification Outstanding Recorded Investment	$ 8,830	$ 8,524
Post-Modification Outstanding Recorded Investment	8,304	8,145
Charge-offs	526	379
Specific Reserves	$ 2,443	$ 3,441
Accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	13	12
Pre-Modification Outstanding Recorded Investment	$ 2,719	$ 2,495
Post-Modification Outstanding Recorded Investment	2,719	2,495
Specific Reserves	$ 279	$ 182
Non-accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	15	18
Pre-Modification Outstanding Recorded Investment	$ 6,111	$ 6,029
Post-Modification Outstanding Recorded Investment	5,585	5,650
Charge-offs	526	379
Specific Reserves	$ 2,164	$ 3,259
Commercial Real Estate \| Accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	9	8
Pre-Modification Outstanding Recorded Investment	$ 2,425	$ 2,187
Post-Modification Outstanding Recorded Investment	2,425	2,187
Specific Reserves	$ 205	$ 104
Commercial Real Estate \| Non-accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	5	4
Pre-Modification Outstanding Recorded Investment	$ 2,274	$ 1,609
Post-Modification Outstanding Recorded Investment	1,911	1,362
Charge-offs	363	247
Specific Reserves	$ 414	$ 102
Commercial and Industrial \| Accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	1	1
Pre-Modification Outstanding Recorded Investment	$ 74	$ 78
Post-Modification Outstanding Recorded Investment	74	78
Specific Reserves	$ 74	$ 78
Commercial and Industrial \| Non-accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	10	14
Pre-Modification Outstanding Recorded Investment	$ 3,837	$ 4,420
Post-Modification Outstanding Recorded Investment	3,674	4,288
Charge-offs	163	132
Specific Reserves	$ 1,750	$ 3,157
Residential Real Estate \| Accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	3	3
Pre-Modification Outstanding Recorded Investment	$ 220	$ 230
Post-Modification Outstanding Recorded Investment	$ 220	$ 230

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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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No definition available.

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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=121611835&loc=SL6953676-111524

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

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

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Reflects the amount of the write-down related to a troubled debt restructuring.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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