Significant Accounting Policies Significant Accounting Policies (Equity Method Investment and Joint Venture) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Schedule of Equity Method Investments [Line Items]
Investment Commitment in Joint Venture	$ 76.0
E2 [Member]
Schedule of Equity Method Investments [Line Items]
Payments to Acquire Interest in Joint Venture	$ 60.7
Noncontrolling Interest, Ownership Percentage by Parent	93.70%
E2 Appalachian Compression, LLC [Member] [Member]
Schedule of Equity Method Investments [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	92.50%