Commitments and Contingencies, Liquidity Option Agreement (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Oct. 02, 2014
Liquidity Option Agreement [Abstract]
Purchase price adjustment to goodwill	$ 1,454.1
Change in fair value of Liquidity Option Agreement	$ 25.4	$ 0.0	$ 0.0
Liquidity Option Agreement [Member]
Liquidity Option Agreement [Abstract]
Other Commitments, Description	In connection with Step 1 of the Oiltanking acquisition, we entered into the Liquidity Option Agreement (“Liquidity Option”) with OTA and M&B, whereby we granted M&B the option to sell to us 100% of the issued and outstanding capital stock of OTA at any time within a 90-day period commencing on February 1, 2020. The aggregate consideration to be paid by us for OTA’s capital stock would equal 100% of the then-current fair market value of the Enterprise common units owned by OTA at the exercise date. If a Trigger Event occurs (as defined in the underlying agreements), the Liquidity Option may be exercised earlier within a 135-day period following notice of such event.
Level 3 [Member] | Liquidity Option Agreement [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair value inputs, assumed long-term debt	$ 2,200.0
Fair value inputs, Interest rate on assumed debt of OTA following option exercise	6.4% over 30 years
Fair value inputs, federal and state tax rate (in hundredths)	38.00%
Cash flow projections discount rate (in hundredths)	7.50%
Fair value inputs, weighted-average expected ownership percentage of contributed units at beginning of option period (in hundredths)	0.789
Liquidity Option Agreement [Abstract]
Liquidity Option Agreement	$ 245.1	$ 219.7
Level 3 [Member] | Liquidity Option Agreement [Member] | Minimum [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair value inputs, Expected life of OTA following option exercise (in years)	1
Fair value inputs, Estimated growth rates in Enterprise earnings before interest, taxes, depreciation and amortization (in hundredths)	2.00%
Fair value inputs, OTA ownership interest in Enterprise common units (in hundredths)	1.90%
Fair value inputs, Forecasted yield on Enterprise common units (in hundredths)	5.80%
Level 3 [Member] | Liquidity Option Agreement [Member] | Maximum [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair value inputs, Expected life of OTA following option exercise (in years)	30
Fair value inputs, Estimated growth rates in Enterprise earnings before interest, taxes, depreciation and amortization (in hundredths)	15.00%
Fair value inputs, OTA ownership interest in Enterprise common units (in hundredths)	2.70%
Fair value inputs, Forecasted yield on Enterprise common units (in hundredths)	6.60%
Oiltanking Partners L.P. - Step 1 [Member]
Business Acquisition [Line Items]
Common units issued in connection with acquisition (in units)		54,807,352
Liquidity Option Agreement [Abstract]
Liquidity Option Agreement				$ 219.7
Liquidity Option Agreement valuation adjustment		$ 100.3
Purchase price adjustment to goodwill		$ 100.3