Schedule I - Parent Only - Condensed Statement of Cash Flows (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net income (loss) from continuing operations				$ (888.2)	$ (1,409.7)	$ 250.7
Adjustments to reconcile net income (loss) to net cash provided by operating activities, net of assets acquired or liabilities assumed:
Income from unconsolidated affiliates				19.9	(20.4)	(18.9)
Deferred tax expense				2.1	22.6	67.4
Non-cash unit-based compensation				30.3	36.1	19.6
Amortization of debt issue cost				3.9	3.3	1.9
Impairments	$ 873.3	$ 764.2	$ 799.2	873.3	1,563.4
Changes in assets and liabilities:
Accounts payable, and other accrued liabilities				132.3	(171.4)	(16.9)
Net cash provided by operating activities				666.4	628.4	458.9
Cash flows from investing activities:
Acquisition of business				(791.5)	(524.2)	(357.9)
Distribution from unconsolidated affiliates				54.6	21.1	10.9
Investment in unconsolidated affiliates				(73.8)	(25.8)	(5.7)
Net cash used in investing activities				(1,380.3)	(1,097.3)	(1,148.6)
Cash flows from financing activities:
Proceeds from borrowings				2,150.4	3,204.4	3,367.8
Payments on borrowings				(1,917.5)	(2,134.3)	(2,792.7)
Debt refinancing cost				(4.7)	(9.6)	(19.7)
Conversion of restricted units, net of units withheld for taxes				(1.2)	(2.9)	(1.1)
Proceeds from issuance of common units				167.5	24.4	412.0
Distribution to members				(185.4)	(162.8)	(89.0)
Net cash provided by financing activities				707.6	418.5	758.1
Net increase (decrease) in cash and cash equivalents				(6.3)	(50.4)	68.4
Cash and cash equivalents, beginning of period	18.0			18.0	68.4
Cash and cash equivalents, end of period		18.0		11.7	18.0	68.4
Parent Company
Cash flows from operating activities:
Net income (loss) from continuing operations				(460.0)	(357.0)	126.0
Adjustments to reconcile net income (loss) to net cash provided by operating activities, net of assets acquired or liabilities assumed:
Income from unconsolidated affiliates				145.1	325.5	(185.7)
Deferred tax expense				2.8	23.9
Non-cash unit-based compensation				0.4	0.4
Amortization of debt issue cost				0.1	0.3
Impairments				307.0
Changes in assets and liabilities:
Accounts receivable, prepaid expenses and other				10.7	(8.5)
Accounts payable, and other accrued liabilities				0.1	(1.8)
Net cash provided by operating activities				6.2	(17.2)
Cash flows from investing activities:
Acquisition of business				(237.1)
Distribution from unconsolidated affiliates				202.3	186.3
Investment in unconsolidated affiliates				(39.5)	(50.0)
Net cash used in investing activities				(74.3)	136.3
Cash flows from financing activities:
Proceeds from borrowings				92.7
Payments on borrowings				(64.9)
Debt refinancing cost					(0.1)
Conversion of restricted units, net of units withheld for taxes				(1.2)	(2.9)
Proceeds from issuance of common units				214.9
Distribution to members				(185.4)	(162.8)
Net cash provided by financing activities				56.1	(165.8)
Net increase (decrease) in cash and cash equivalents				(12.0)	(46.7)
Cash and cash equivalents, beginning of period	$ 12.1			12.1	58.8
Cash and cash equivalents, end of period		$ 12.1		0.1	12.1	$ 58.8
Loss from issuance of Partnership units				$ 18.9	$ 13.7