Interest Rate Swaps (Narrative) (Details) (USD $)												9 Months Ended
	Sep. 30, 2012	Mar. 31, 2011	Jun. 23, 2008	Mar. 19, 2008	Mar. 31, 2011 RX0583-T1 [Member]	Jun. 30, 2011 RX0583-T2 [Member]	Mar. 31, 2011 RX0584-T1 [Member]	Mar. 31, 2011 $6.0 Million Of Variable-Rate Debt Through March 2011 [Member]	Mar. 31, 2013 $33.0 Million Of Variable-Rate Debt Through March 2013 [Member]	Jun. 30, 2011 $3.0 Million Of Variable-Rate Debt Through June 2011 [Member]	Jun. 30, 2013 $3.0 Million Of Variable-Rate Debt Through June 2013 [Member]	Sep. 30, 2012 Maximum [Member]	Sep. 30, 2012 Minimum [Member]
Derivative [Line Items]
Aggregate indebtedness	$ 36,000,000		$ 6,000,000	$ 39,000,000
Debt, variable-rate								6,000,000	33,000,000	3,000,000	3,000,000
Swaps matured		5,000,000				3,000,000
Swap amount matured					$ 1,000,000		$ 4,000,000
Libor margin rate												2.25%	2.00%