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Loans (Narrative) (Details) | 12 Months Ended
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Dec. 31, 2019 USD ($) contract | Dec. 31, 2018 USD ($) contract | Dec. 31, 2017 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, related parties | $ 18,600,000 | $ 10,300,000 |
Loans, related parties, new borrowings | 9,800,000 |  |
Loans, related parties, repayments and other reductions | 1,600,000 |  |
Past due greater than 90 days and still accruing interest | 0 | 0 |
Interest income recognized on nonaccrual loans | 0 | 0 | $ 0
Estimated interest income | $ 508,000 | $ 294,000 | $ 481,000
Number of loans modified as TDR | contract | 0 | 0 |
Number of loans modified as TDR that defaulted | contract | 0 | 0 |
Days past due when loans are generally placed on nonaccrual status, in days | 90 days | 90 days |
Consumer Overdrafts [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Past due greater than 90 days and still accruing interest | $ 6,000 | $ 8,000 |

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- Definition 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=118936363&loc=SL6953676-111524 + Details
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- Definition Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524 + Details
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- Definition Amount of financing receivable 90 days or more past due and still accruing. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 16 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919258-210447 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5111-111524 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 80 -URI http://asc.fasb.org/extlink&oid=118955255&loc=SL82922355-210448 + Details
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- Definition Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524 + Details
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