Investment in Unconsolidated Affiliate (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013	Dec. 31, 2013
Schedule of Equity Method Investments [Line Items]
Undistributed Earnings, Basic	$ (9.2)			$ (24.5)
Equity Method Investments	276.1			276.1			61.1
Distribution of earnings from equity investment				6.3		10.9
Income from equity investments	5.6		5.8	14.3		10.2
Gulf Coast Fractionators
Schedule of Equity Method Investments [Line Items]
Undistributed Earnings, Basic				13.1
Equity Method Investments	56.0	[1]		56.0	[1]		61.1	[1]
Distribution of earnings from equity investment	5.2		12.0	5.2	[2]	12.0
Equity Method Investment, Ownership Percentage	38.75%			38.75%
Income from equity investments	5.2		5.8	13.2	[2]	10.2
Howard Energy Partners
Schedule of Equity Method Investments [Line Items]
Equity Method Investments	220.1			220.1			0
Distribution of earnings from equity investment	3.0		0	8.7	[2]	0
Equity Method Investment, Ownership Percentage	30.60%			30.60%
Income from equity investments	0.4		0	1.1	[2]	0
Total
Schedule of Equity Method Investments [Line Items]
Distribution of earnings from equity investment	8.2		12.0	13.9	[2]	12.0
Income from equity investments	$ 5.6		$ 5.8	$ 14.3	[2]	$ 10.2

[1] Devon retained $13.1 million of the undistributed earnings due from GCF, as of March 7, 2014 when the GCF contractual right allocating the benefits and burdens of the 38.75% ownership interest in GCF to the Partnership became effective. The $13.1 million of the undistributed earnings was reflected as a reduction in the GCF investment on March 7, 2014.

[2] Includes income and distributions for the period March 7, 2014 through September 30, 2014 for Howard Energy Partners.