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Derivatives And Risk Management (Interest Rate Swap Agreements) (Details) - Interest Rate Swap [Member] $ in Thousands | 9 Months Ended | 12 Months Ended
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Sep. 30, 2019 USD ($) Caontracts | Dec. 31, 2018 USD ($) Caontracts
2019 |  |
Derivatives, Fair Value [Line Items] |  |
Number of Interest Rate Derivatives Held | Caontracts |  | 6
Derivative, Notional Amount | $ |  | $ 70,000
Mandatory Cash Settlement Date |  | 2019
2020 |  |
Derivatives, Fair Value [Line Items] |  |
Number of Interest Rate Derivatives Held | Caontracts | 7 | 6
Derivative, Notional Amount | $ | $ 70,000 | $ 60,000
Mandatory Cash Settlement Date | 2020 | 2020
2021 |  |
Derivatives, Fair Value [Line Items] |  |
Number of Interest Rate Derivatives Held | Caontracts | 3 | 2
Derivative, Notional Amount | $ | $ 35,000 | $ 25,000
Mandatory Cash Settlement Date | 2021 | 2021
2022 |  |
Derivatives, Fair Value [Line Items] |  |
Number of Interest Rate Derivatives Held | Caontracts | 10 | 7
Derivative, Notional Amount | $ | $ 110,000 | $ 80,000
Mandatory Cash Settlement Date | 2022 | 2022

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Description of the relevant terms of the derivative. Includes the type of instrument, risk being hedged, notional amount, counterparty, inception date, maturity date, relevant interest rates, strike price, cap price, and floor price. + References No definition available. + Details
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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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- Definition Number of interest rate derivative instruments held by the entity at the reporting date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959 + Details
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- Details
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