Equity-based Awards, Unit Option Awards (Details) (Unit Option Awards [Member], USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Unit Option Awards [Member]
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)	4,050,000	[1],[2]	5,522,280		7,506,840
Exercised (in units)	(2,720,000)		(1,472,280)		(1,484,560)
Forfeited (in units)	(60,000)				(500,000)
End of period (in units)	1,270,000	[1],[2]	4,050,000	[1],[2]	5,522,280
Options outstanding, weighted-average strike price [Roll Forward]
Weighted average strike price, beginning of period (in dollars per unit)	$ 13.24	[1],[2]	$ 13.71		$ 14.04
Weighted average strike price, exercised (in dollars per unit)	$ 11.83		$ 14.98		$ 15.39
Weighted average strike price, forfeited (in dollars per unit)	$ 16.14				$ 13.73
Weighted average strike price, end of period (in dollars per unit)	$ 16.14	[1],[2]	$ 13.24	[1],[2]	$ 13.71
Weighted average remaining contractual term	1 year	[1],[2]
Aggregate intrinsic value	$ 25.4	[1],[2],[3]
Total intrinsic value of unit option awards exercised during period	57.5		19.8		14.6
Cash received from EPCO in connection with the exercise of unit option awards	33.4		11.5		10.2
Unit option-related cash reimbursements to EPCO	$ 57.5		$ 19.8		$ 14.0

[1] At December 31, 2014 and 2013, we were committed to issue 1,270,000 and 4,050,000, respectively, of our common units if all outstanding unit option awards were exercised. All of the unit option awards outstanding at December 31, 2014 vested during 2014 and became exercisable beginning in February 2015.

[2] None of the unit option awards outstanding at December 31, 2014, 2013 and 2012 were exercisable as of such dates, respectively.

[3] Aggregate intrinsic value reflects fully vested unit option awards at the date indicated.