Interest Rate Derivative Agreements (Details) (USD $)		9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2010 Bank of New York Mellon [Member]	Dec. 31, 2012 Bank of New York Mellon [Member]	Sep. 30, 2010 Barclays Bank PLC [Member]	Dec. 31, 2012 Barclays Bank PLC [Member]	Sep. 30, 2010 Royal Bank of Canada [Member]	Dec. 31, 2012 Royal Bank of Canada [Member]
Derivative [Line Items]
Derivative, Purchase Date		Sep. 02, 2010		Sep. 02, 2010		Sep. 02, 2010
Notional Amount of Interest Rate Derivatives	$ 31,900,000		$ 31,936,667		$ 31,936,667		$ 31,936,667
Derivative, Fixed Interest Rate	3.00%		3.00%		3.00%		3.00%
Derivative, Maturity Date at a point in time			Sep. 01, 2017		Sep. 01, 2017		Sep. 01, 2017
Deriviative at purchase price			$ 921,000		$ 845,600		$ 928,000