Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Statement of Cash Flows [Abstract]
Net income from continuing operations	$ 179.4	$ 87.6
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	195.8	138.6
Accretion expense	0.4	0.3
Gain on Extinguishment of Debt	(3.2)	0
Deferred tax expense (benefit)	53.7	10.8
Non-cash stock-based compensation	12.8	0
Loss on derivatives recognized in net income	1.9	0
Cash Paid On Derivatives	(1.7)	0
Amortization of debt issue costs	0.8	0
Amortization Of Premium On Notes	(1.7)	0
Distribution of earnings from equity investment	6.3	10.9
Income from equity investments	(14.3)	(10.2)
Changes in assets and liabilities:
Accounts receivable, accrued revenue and other	26.2	0
Natural gas and natural gas liquids, prepaid expenses and other	(27.0)	(1.1)
Accounts payable, accrued gas and crude oil purchases and other accrued liabilities	(67.4)	8.1
Net cash provided by operating activities	362.0	245.0
Cash flows from investing activities:
Additions to property and equipment	(511.8)	(201.3)
Acquisition of business	(51.9)	0
Deposit for acquisition	(23.5)	0
Investment in equity investment company	(5.7)	0
Distribution from equity investment company in excess of earnings	7.6	1.1
Net cash used in investing activities	(585.3)	(200.2)
Cash flows from financing activities:
Proceeds from borrowings	2,170.3	0
Payments on borrowings	(1,765.2)	0
Payments on capital lease obligations	(1.8)	0
Increase in drafts payable	(2.6)	0
Debt refinancing costs	(7.5)	0
Proceeds from issuance of Partnership units	71.9	0
Proceeds from exercise of Partnership unit options	0.4	0
Conversion of restricted stock for common, net of shares withheld for taxes	(1.0)	0
Conversion of Partnerships restricted units for common, net of shares withheld for taxes	(0.5)	0
Distribution to members	(51.0)	0
Distributions to predecessor	(27.2)	(117.7)
Distributions to Non-controlling Interests	(124.2)	0
Contributions by non-controlling Interests	1.2	0
Net cash provided by financing activities	262.8	(117.7)
Net cash provided by operating activities	5.0	11.2
Net cash used in investing activities	(0.6)	143.7
Net cash used in financing activities – net distributions to Devon and non-controlling interests	(4.4)	(97.6)
Net cash provided by discontinued operations	0	57.3
Net increase (decrease) in cash and cash equivalents	39.5	(15.6)
Cash and cash equivalents, beginning of period	0	15.6
Cash and cash equivalents, end of period	39.5
Cash paid for interest	19.9	0
Cash paid for income taxes	$ 7.4	$ 0