Accrued And Other Liabilities (Schedule Of Accrued And Other Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Accrued And Other Liabilities [Line Items]
Accrued operating expenses	$ 21,072	$ 11,173
Accrued capital spending	15,561	6,109
Accrued production and other taxes	10,090	7,401
Senior notes accrued interest	4,625	11,563
Gas imbalance liability	4,775	5,351
Hedge settlement payable	2,410
Other	2,552	1,187
Total accrued and other liabilities	64,585	46,284
Class C Preferred Convertible Unitholder [Member]
Accrued And Other Liabilities [Line Items]
Distributions payable	$ 3,500	$ 3,500