Summary Of Significant Accounting Policies (Oil Entitlement Assets and Liabilities) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013 Mcf	Dec. 31, 2012 Mcf
Oil Entitlement Assets and Liabilities [Line Items]
Gas Entitlement Assets Amount	$ 7.4	$ 6.8
Gas Entitlement Assets Volumes In Mmcf	2,990	2,870
Gas Entitlement Liabilities Amount	$ 2.5	$ 1.9
Gas Entitlement Liabilities Volumes In Mmcf	715	582