Derivative Instruments, Hedging Activities and Fair Value Measurements, Level 3 Recurring Valuation Techniques (Details) (Level 3 [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Liability - Liquidity Option Agreement [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value Measurements, Valuation Techniques	Discounted cash flow
Input description	Expected life of OTA following option exercise, Estimated growth rates in Enterprise’s earnings before interest, taxes, depreciation and amortization, OTA ownership interest in Enterprise common units, Interest rate on assumed debt of OTA following option exercise, Forecasted yield on Enterprise common units, Federal and state tax rate
Fair value inputs, Expected life of OTA following option exercise (in years)	30
Fair value inputs, Interest rate on assumed debt of OTA following option exercise	4.9% over 30 years
Fair value inputs, federal and state tax rate (in hundredths)	38.00%
Liability - Liquidity Option Agreement [Member] | Minimum [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair value inputs, Estimated growth rates in Enterprise earnings before interest, taxes, depreciation and amortization (in hundredths)	3.00%
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)	4.00%
Liability - Liquidity Option Agreement [Member] | Maximum [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair value inputs, Estimated growth rates in Enterprise earnings before interest, taxes, depreciation and amortization (in hundredths)	14.00%
Fair value inputs, OTA ownership interest in Enterprise common units (in hundredths)	2.80%
Fair value inputs, Forecasted yield on Enterprise common units (in hundredths)	5.50%
Asset commodity derivatives - Crude oil [Member] | Liability commodity derivatives - Crude oil [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value Measurements, Valuation Techniques	Discounted cash flow
Input description	Forward commodity prices
Asset commodity derivatives - Crude oil [Member] | Liability commodity derivatives - Crude oil [Member] | Minimum [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair value inputs, forward commodity price (in dollars per unit)	49.26	89.55
Asset commodity derivatives - Crude oil [Member] | Liability commodity derivatives - Crude oil [Member] | Maximum [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair value inputs, forward commodity price (in dollars per unit)	53.27	98.54
Assets commodity derivatives - Natural gas [Member] | Liability commodity derivatives - Natural gas [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value Measurements, Valuation Techniques	Discounted cash flow
Input description	Forward commodity prices
Assets commodity derivatives - Natural gas [Member] | Liability commodity derivatives - Natural gas [Member] | Minimum [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair value inputs, forward commodity price (in dollars per unit)	3.05
Assets commodity derivatives - Natural gas [Member] | Liability commodity derivatives - Natural gas [Member] | Maximum [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair value inputs, forward commodity price (in dollars per unit)	4.09
Fair Value, Measurements, Recurring [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Financial assets	$ 1.0
Financial liabilities	120.0
Fair Value, Measurements, Recurring [Member] | Liability commodity derivatives - Crude oil [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Financial liabilities	0.4	0.7
Fair Value, Measurements, Recurring [Member] | Liability commodity derivatives - Natural gas [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Financial liabilities	0.2
Fair Value, Measurements, Recurring [Member] | Liability - Liquidity Option Agreement [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Financial liabilities	119.4
Fair Value, Measurements, Recurring [Member] | Asset commodity derivatives - Crude oil [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Financial assets	1.0	3.9
Fair Value, Measurements, Recurring [Member] | Assets commodity derivatives - Natural gas [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Financial assets	$ 0