Equity-Based Awards, Unit Option Awards (Details) - Unit Option Awards [Member] - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Summary of awards activity, options [Roll Forward]
Beginning of period (in units)	1,270,000	[1]	4,050,000		5,522,280
Exercised (in units)	(1,270,000)		(2,720,000)		(1,472,280)
Forfeited (in units)			(60,000)
End of period (in units)	0		1,270,000	[1]	4,050,000
Options outstanding, weighted-average strike price [Roll Forward]
Weighted average strike price, beginning of period (in dollars per unit)	$ 16.14		$ 13.24		$ 13.71
Weighted average strike price, exercised (in dollars per unit)	16.14		11.83		14.98
Weighted average strike price, forfeited (in dollars per unit)			16.14
Weighted average strike price, end of period (in dollars per unit)	$ 0		$ 16.14		$ 13.24
Total intrinsic value of unit option awards exercised during period	$ 21.7		$ 57.5		$ 19.8
Cash received from EPCO in connection with the exercise of unit option awards	13.1		33.4		11.5
Unit option award-related cash reimbursements to EPCO	$ 21.7		$ 57.5		$ 19.8

[1] All of the unit option awards outstanding at December 31, 2014 vested during 2014 and were exercised during 2015.