Fair Value Measurement (Textual) (Details) (USD $)	Mar. 31, 2014
Debt Instrument [Line Items]
Long-term Debt	$ 1,732,500,000
ENLC Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Debt	103,500,000
Other Debt Obligations [Member]
Debt Instrument [Line Items]
Long-term Debt	15,000,000
Line of Credit Facility, Amount Outstanding	14,500,000
Unsecured Debt [Member] | 2022 [Member]
Debt Instrument [Line Items]
Senior Notes	226,000,000
8.875% [Member] | Unsecured Debt [Member] | 2018 [Member]
Debt Instrument [Line Items]
Senior Notes	198,200,000
Debt Instrument, Interest Rate, Stated Percentage	8.875%
5.6% [Member] | Unsecured Debt [Member] | 2044 [Member]
Debt Instrument [Line Items]
Senior Notes	346,700,000
Debt Instrument, Interest Rate, Stated Percentage	5.60%
4.4% [Member] | Unsecured Debt [Member] | 2024 [Member]
Debt Instrument [Line Items]
Senior Notes	446,300,000
Debt Instrument, Interest Rate, Stated Percentage	4.40%
2.7% [Member] | Unsecured Debt [Member] | 2019 [Member]
Debt Instrument [Line Items]
Senior Notes	397,000,000
Debt Instrument, Interest Rate, Stated Percentage	2.70%
7.125% [Member] | Unsecured Debt [Member] | 2022 [Member]
Debt Instrument [Line Items]
Senior Notes	$ 225,800,000
Debt Instrument, Interest Rate, Stated Percentage	7.125%