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, 2022 USD ($) Loan	Dec. 31, 2021 USD ($) Loan
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	14	15
Pre-Modification Outstanding Recorded Investment	$ 4,072	$ 4,706
Post-Modification Outstanding Recorded Investment	2,799	3,433
Charge-offs	1,273	1,273
Specific Reserves	$ 371	$ 457
Accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	7	8
Pre-Modification Outstanding Recorded Investment	$ 1,456	$ 1,927
Post-Modification Outstanding Recorded Investment	1,456	1,927
Specific Reserves	$ 208	$ 346
Non-accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	7	7
Pre-Modification Outstanding Recorded Investment	$ 2,616	$ 2,779
Post-Modification Outstanding Recorded Investment	1,343	1,506
Charge-offs	1,273	1,273
Specific Reserves	$ 163	$ 111
Commercial Real Estate \| Accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	4	5
Pre-Modification Outstanding Recorded Investment	$ 1,244	$ 1,703
Post-Modification Outstanding Recorded Investment	1,244	1,703
Specific Reserves	$ 158	$ 215
Commercial Real Estate \| Non-accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	4	4
Pre-Modification Outstanding Recorded Investment	$ 899	$ 1,034
Post-Modification Outstanding Recorded Investment	783	918
Charge-offs	116	116
Specific Reserves	$ 163	$ 111
Commercial and Industrial \| Accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	1	1
Pre-Modification Outstanding Recorded Investment	$ 50	$ 56
Post-Modification Outstanding Recorded Investment	50	56
Specific Reserves	$ 50	$ 131
Commercial and Industrial \| Non-accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	3	3
Pre-Modification Outstanding Recorded Investment	$ 1,717	$ 1,745
Post-Modification Outstanding Recorded Investment	560	588
Charge-offs	1,157	1,157
Specific Reserves	$ 0	$ 0
Residential Real Estate \| Accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	2	2
Pre-Modification Outstanding Recorded Investment	$ 162	$ 168
Post-Modification Outstanding Recorded Investment	162	168
Specific Reserves	$ 0	$ 0

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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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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
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
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