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Off-Balance-Sheet Financial Instruments and Concentrations of Credit Risk (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) derivative | Dec. 31, 2019 USD ($)
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Off-balance-sheet financial instruments | $ 231,756,000 | $ 195,577,000
Designated as Hedging Instrument | Interest Rate Swap | Cash Flow Hedging |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Number of derivative instruments (derivative) | derivative | 11 |
Notional principal amounts | $ 260,000,000 | 150,000,000
Unrealized loss on derivative | $ 4,932,000 |
Designated as Hedging Instrument | Customer Loan Interest Swap | Cash Flow Hedging |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Number of derivative instruments (derivative) | derivative | 5 |
Notional principal amounts | $ 65,974,000 |
Unused lines, collateralized by residential real estate |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Off-balance-sheet financial instruments | 89,852,000 | 81,193,000
Other unused commitments |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Off-balance-sheet financial instruments | 102,963,000 | 90,186,000
Standby letters of credit |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Off-balance-sheet financial instruments | 4,415,000 | 4,496,000
Commitments to extend credit |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Off-balance-sheet financial instruments | $ 34,526,000 | $ 19,702,000

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- Definition Nominal or face amount used to calculate payments on the derivative liability. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959 + Details
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