Allowance for Loan and Lease Losses and Reserve for Unfunded Commitments - Summary of TDR's by Loan Category (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) Loan	Dec. 31, 2018 USD ($) Loan	Dec. 31, 2017 USD ($) Loan
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	27	22	10
Pre-Modification Outstanding Recorded Investment	$ 12,700	$ 11,039	$ 3,117
Post-Modification Outstanding Recorded Investment	10,571	9,127	2,630
Charge-offs	2,129	1,912	487
Specific Reserves	$ 2,166	$ 2,246	$ 357
Accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	9	7	4
Pre-Modification Outstanding Recorded Investment	$ 1,771	$ 1,813	$ 1,061
Post-Modification Outstanding Recorded Investment	1,771	1,813	$ 1,061
Specific Reserves	$ 341	$ 213
Non-accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	18	15	6
Pre-Modification Outstanding Recorded Investment	$ 10,929	$ 9,226	$ 2,056
Post-Modification Outstanding Recorded Investment	8,800	7,314	1,569
Charge-offs	2,129	1,912	487
Specific Reserves	$ 1,825	$ 2,033	$ 357
Commercial Real Estate \| Accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	5	4	3
Pre-Modification Outstanding Recorded Investment	$ 1,451	$ 1,508	$ 912
Post-Modification Outstanding Recorded Investment	1,451	1,508	$ 912
Specific Reserves	$ 223	$ 113
Commercial Real Estate \| Non-accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	6	9	2
Pre-Modification Outstanding Recorded Investment	$ 2,777	$ 2,512	$ 743
Post-Modification Outstanding Recorded Investment	2,600	2,471	743
Charge-offs	177	41
Specific Reserves	$ 513	$ 743	$ 111
Commercial and Industrial \| Accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	2	2
Pre-Modification Outstanding Recorded Investment	$ 129	$ 191
Post-Modification Outstanding Recorded Investment	129	191
Specific Reserves	$ 118	$ 100
Commercial and Industrial \| Non-accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	11	6	3
Pre-Modification Outstanding Recorded Investment	$ 8,048	$ 6,714	$ 1,246
Post-Modification Outstanding Recorded Investment	6,096	4,843	759
Charge-offs	1,952	1,871	487
Specific Reserves	$ 1,312	$ 1,290	$ 246
Residential Real Estate \| Accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	2	1	1
Pre-Modification Outstanding Recorded Investment	$ 191	$ 114	$ 149
Post-Modification Outstanding Recorded Investment	$ 191	$ 114	$ 149
Residential Real Estate \| Non-accruing
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	1		1
Pre-Modification Outstanding Recorded Investment	$ 104		$ 67
Post-Modification Outstanding Recorded Investment	$ 104		$ 67

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

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
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