Derivatives And Risk Management (Interest Rate Swap Agreements) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013 Caontracts	Dec. 31, 2012 Caontracts
Derivatives, Fair Value [Line Items]
Secured Debt	$ 1,376,700,000	$ 1,336,700,000
Derivative, Fair Value, Amount Offset Against Collateral, Net	8,732,000	9,707,000
2013 | Interest Rate Swap Agreements [Member]
Derivatives, Fair Value [Line Items]
Number of contracts		2
Derivative, Notional Amount		85,000,000
Derivative, Maturity Date		Dec. 31, 2013
2014 | Interest Rate Swap Agreements [Member]
Derivatives, Fair Value [Line Items]
Number of contracts	2	2
Derivative, Notional Amount	50,000,000	50,000,000
Derivative, Maturity Date	Dec. 31, 2014	Dec. 31, 2014
2015 | Interest Rate Swap Agreements [Member]
Derivatives, Fair Value [Line Items]
Number of contracts	2	1
Derivative, Notional Amount	45,000,000	25,000,000
Derivative, Maturity Date	Dec. 31, 2015	Dec. 31, 2015
2016 | Interest Rate Swap Agreements [Member]
Derivatives, Fair Value [Line Items]
Number of contracts	2
Derivative, Notional Amount	40,000,000
Derivative, Maturity Date	Dec. 31, 2016
2017 | Interest Rate Swap Agreements [Member]
Derivatives, Fair Value [Line Items]
Number of contracts	1
Derivative, Notional Amount	15,000,000
Derivative, Maturity Date	Dec. 31, 2017
2018 | Interest Rate Swap Agreements [Member]
Derivatives, Fair Value [Line Items]
Number of contracts	4
Derivative, Notional Amount	95,000,000
Derivative, Maturity Date	Dec. 31, 2018
2016 | First Mortgage [Member]
Derivatives, Fair Value [Line Items]
Secured Debt	$ 90,000,000	$ 0