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, 2012		Dec. 31, 2011		Dec. 31, 2010
Summary of awards activity, options [Roll Forward]
Beginning of period (in units)	3,753,420		3,753,420		3,825,920
Granted (in units)					785,000	[1]
Exercised (in units)	(742,280)				(857,500)
Forfeited (in units)	(250,000)
End of period (in units)	2,761,140	[2],[3]	3,753,420		3,753,420
Options outstanding, weighted-average strike price [Roll Forward]
Weighted average strike price, beginning of period (in dollars per unit)	$ 28.08		$ 28.08		$ 26.52
Weighted average strike price, granted (in dollars per unit)					$ 32.26	[1]
Weighted average strike price, exercised (in dollars per unit)	$ 30.77				$ 24.98
Weighted average strike price, forfeited (in dollars per unit)	$ 27.45
Weighted average strike price, end of period (in dollars per unit)	$ 27.41	[2],[3]	$ 28.08		$ 28.08
Weighted average remaining contractual term	2 years	[2],[3]
Aggregate intrinsic value	$ 13.0	[2],[3],[4]
Option awards vested during period (in units)	676,000
Awards exercisable in 2013 (in units)	676,000
Awards exercisable in 2014 (in units)	1,390,140
Awards exercisable in 2015 (in units)	695,000
Aggregate grant date fair value					2.3
Weighted-average grant date market price of option awards issued					$ 32.26
Expected life (in years)					4 years 11 months
Weighted-average risk-free interest rate (in hundredths)					2.50%
Weighted-average expected distribution yield (in hundredths)					6.90%
Weighted-average expected unit price volatility (in hundredths)					23.30%
Grant Date Estimated Forfeiture Rate Equity Awards					4.60%
Total intrinsic value of unit option awards exercised during period	14.6		0		10.6
Cash received from EPCO in connection with the exercise of unit option awards	10.2	[5]	0	[5]	7.2	[5]
Unit option-related cash reimbursements to EPCO	14.0	[5]	0	[5]	10.6	[5]
Unrecognized Compensation Expense [Abstract]
Unrecognized compensation cost	1.0
Recognition period for total unrecognized compensation cost	0 years 10 months
Enterprise [Member]
Unrecognized Compensation Expense [Abstract]
Unrecognized compensation cost	$ 0.8

[1] Aggregate grant date fair value of these unit option awards issued during 2010 was $2.3 million based on the following assumptions: (i) a weighted-average grant date market price of our common units of $32.26 per unit; (ii) weighted-average expected life of options of 4.9 years; (iii) weighted-average risk-free interest rate of 2.5%; (iv) weighted-average expected distribution yield on our common units of 6.9%; and (v) weighted-average expected unit price volatility on our common units of 23.3%. An estimated annual forfeiture rate of 4.6% was applied to awards granted during 2010.

[2] None of the unit option awards outstanding at December 31, 2012, 2011 and 2010 were exercisable.

[3] At December 31, 2012 and 2011, we were committed to issue 2,761,140 and 3,753,420, respectively, of our common units if all outstanding unit option awards were exercised. Option awards outstanding at December 31, 2012 include 676,000 awards that vested during 2012 and became exercisable beginning in February 2013. Of the remaining outstanding option awards at December 31, 2012, 1,390,140 and 695,000 will vest in 2013 and 2014, respectively. These unit option awards become exercisable in the calendar year following the year in which they vest.

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

[5] For the year ended December 31, 2012, we classified cash receipts from EPCO and reimbursements to EPCO related to the exercise of unit options as a component of other financing activities on our Statement of Consolidated Cash Flows. For comparative purposes, amounts for 2010 have been reclassified to conform to the current year presentation. The reclassification of 2010 amounts had no effect on previously reported cash provided by financing activities for that year.