Equity-based Awards, Restricted Unit Awards (Details) (Restricted Common Unit Awards [Member], USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Summary of awards activity, equity instruments other than options [Roll Forward]
Beginning of period (in units)	3,893,486
Granted (in units)	1,723,576	[1],[2]
Vested (in units)	(939,226)	[2]
Forfeited (in units)	(59,460)
End of period (in units)	4,618,376
Restricted units outstanding, weighted-average grant date fair value [Roll Forward]
Weighted-average grant date fair value per unit, at beginning of period (in dollars per unit)	$ 40.87	[3]
Granted weighted-average grant date fair value per unit (in dollars per unit)	$ 57.11	[1],[2],[3]
Vested weighted-average grant date fair value per unit (in dollars per unit)	$ 43.42	[2],[3]
Forfeited weighted-average grant date fair value per unit (in dollars per unit)	$ 43.13	[3]
Weighted-average grant date fair value per unit, at end of period (in dollars per unit)	$ 46.38	[3]
Summary of awards activity, equity instruments other than options, additional disclosures [Abstract]
Aggregate grant date fair value	$ 98.4
Grant date market price of common units (in dollars per unit)	$ 57.11
Estimated forfeiture rate (in hundredths)	3.90%
Equity based awards issued to independent directors of the entities' general partner (in units)	9,296
Cash distributions paid to restricted common unitholders	2.6		2.4
Total intrinsic value of restricted common unit awards that vested during period	52.4		32.6
Unrecognized Compensation Expense [Abstract]
Unrecognized compensation cost	128.7
Recognition period for total unrecognized compensation cost	2 years 2 months
Enterprise [Member]
Unrecognized Compensation Expense [Abstract]
Unrecognized compensation cost	$ 118.4

[1] The aggregate grant date fair value of restricted common unit awards issued during 2013 was $98.4 million based on a grant date market price of our common units of $57.11 per unit. An estimated annual forfeiture rate of 3.9% was applied to these awards.

[2] Includes awards granted to the independent directors of the board of directors of Enterprise GP as part of their annual compensation for 2013. A total of 9,296 restricted common unit awards were issued to the independent directors of Enterprise GP, which immediately vested upon issuance.

[3] Determined by dividing the aggregate grant date fair value of awards (before an allowance for forfeitures) by the number of awards issued.