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Loans (Interest written off on nonaccrual loans) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Financing Receivable, Credit Quality Indicator - narrative [Line Items] |  |  |
Interest written off on nonaccrual loans | $ 2,000 | $ 1,671 | $ 1,564
Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, Credit Quality Indicator - narrative [Line Items] |  |  |
Interest written off on nonaccrual loans | 1,972 | 1,475 | 1,296
Consumer [Member] |  |  |
Financing Receivable, Credit Quality Indicator - narrative [Line Items] |  |  |
Interest written off on nonaccrual loans | $ 28 | $ 196 | $ 268

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Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- Definition 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. + References No definition available. + Details
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- Details
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Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |