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Derivative Instruments and Hedging Activities (Narrative) (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) InterestRateDerivative | Dec. 31, 2019 USD ($)
Derivative [Line Items] |  |
Estimated to be reclassified as an increase to interest expense during next twelve months | $ 114,000 |
Derivatives Designated as Hedging Instruments [Member] |  |
Derivative [Line Items] |  |
Notional amount | $ 50,000,000 | $ 100,000,000
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedge of Interest Rate Risk [Member] |  |
Derivative [Line Items] |  |
Number of months hedging exposure to variability in future cash flows for forecasted transactions | 60 months |
Number of outstanding forward starting interest rate Derivative | InterestRateDerivative | 1 |
Notional amount | $ 50,000,000.0 |
Derivative effective date | 2022-04 |

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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: 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 2: 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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