Interest Rate Swaps (Narrative) (Details) (USD $)	3 Months Ended				1 Months Ended
	Dec. 31, 2011	Oct. 31, 2011	Sep. 30, 2011	Dec. 31, 2011 Interest Rate Swap [Member]	Oct. 31, 2011 3.4% Interest Rate Swaps Due 2014 [Member]
Summary of Derivative Instruments by Risk Exposure [Line Items]
Number of interest rate swap agreements		5	4
Notional amount of interest rate swap agreements			$ 50,000,000	$ 50,000,000
Interest rate fixed as result of interest rate swap hedges	3.40%				3.40%
Unrealized loss recognized in OCI	200,000
Outstanding credit facility	$ 250,000,000		$ 200,000,000