Debt (Schedule Of Debt Issuance Costs Associated With Long-Term Obligations) (Details) - USD ($)	Jun. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Long-term Obligations	$ 447,201,998	$ 448,908,517
Unamortized Debt Issuance Costs	2,801,913	2,680,897
Term Loan Facility [Member] | 2011 Series A Bonds [Member]
Debt Instrument [Line Items]
Long-term Obligations	210,999,998	221,666,665
Unamortized Debt Issuance Costs	1,414,754	1,482,791
Term Loan Facility [Member] | 2012 Series A Bonds [Member]
Debt Instrument [Line Items]
Long-term Obligations	194,250,000	205,000,000
Unamortized Debt Issuance Costs	1,151,655	1,198,106
Term Loan Facility [Member] | 2011 CoBank Note [Member]
Debt Instrument [Line Items]
Long-term Obligations		22,241,852
Unamortized Debt Issuance Costs		$ 0
Term Loan Facility [Member] | 2016 CoBank Note [Member]
Debt Instrument [Line Items]
Long-term Obligations	41,952,000
Unamortized Debt Issuance Costs	$ 235,504