Commitments And Contingencies (Narrative) (Details) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended	9 Months Ended
	Jul. 31, 2011 USD ($)	Sep. 30, 2011 USD ($)	Sep. 30, 2011 USD ($) years MMcf MBbls Mcf	Sep. 30, 2011 CAD	Apr. 30, 2011 CAD
Commitments And Contingencies [Abstract]
Estimated construction costs					257.4
Taxes on estimated construction costs					27.6
Liabilities subject to compromise, early contract termination fees				26.4
Minimum volume for contract extension, Mcf			1,000,000,000
Minimum volume delivery in the event of contract extension, cf		106,000,000	106,000,000
Drilling rig contract commitments	12.0
Surety bonds		10.0	10.0
Outstanding letters of credit		34.1	34.1
Senior secured credit facility		42.9	42.9
Issued in support of surety bonds			31.1
Letter of credit terminated			28.9
Loss contingency, loss in period		$ 8.5