|**Long-Term Debt And Loans Payable (Tables)**                               | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
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|**Long Term Debt And Loans Payable [Abstract]**                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Schedule Of Long-Term Debt Future Sinking Fund Payments And Debt Maturities | Interest Rate Range20202021202220232024Thereafter0.00% to0.99%$670$460$461$461$252$1,1701.00% to1.99%1,0169789578357646,1832.00% to2.99%1,8631,9131,9642,0171,6196,2983.00% to3.99%91,52441,28724,6222,0651,7671,133,7764.00% to4.99%29216894991031,554,0355.00% to5.99%6,1916,21578710,81110,61176,9956.00% to6.99%-----31,0007.00% to7.99%574666374--29,1378.00% to8.99%5211,6657217848524839.00% to9.99%2,4004,900---12,000Total$105,051$58,252$29,980$17,072$15,968$2,851,077
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|Interest Rate Range                                                         |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|0.00% to0.99%                                                               | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
|1.00% to1.99%                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|2.00% to2.99%                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|3.00% to3.99%                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|4.00% to4.99%                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|5.00% to5.99%                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|6.00% to6.99%                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|7.00% to7.99%                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|8.00% to8.99%                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|9.00% to9.99%                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Total                                                                       | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
|Summary Of Amounts Recognized In Earnings                                   | Amount of Gain (Loss) Recognized in Income on DerivativesYears Ended December 31,Location of Gain (Loss) Recognized20192018Derivatives not designated as hedging instrument:Interest rate swapsOther (expense) income$(23,742)$(59,779)                                                                                                                                                                                                                                          
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|                                                                            | Location of Gain (Loss) Recognized                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Derivatives not designated as hedging instrument:                           |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Interest rate swaps                                                         | Other (expense) income                                                                                                                                                                                                                                                                                                                                                                                                                                                           

X- DefinitionTabular disclosure of the location and amount of derivative instruments and nonderivative instruments designated as hedging instruments reported before netting adjustments, and the amount of gain (loss) on derivative instruments and nonderivative instruments designated and qualified as hedging instruments.
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