Long-Term Debt (Indebtedness Table) (Details) (USD $)			3 Months Ended						0 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014 Line of Credit [Member] 2019 [Member]	Mar. 31, 2014 ENLC Credit Facility [Member]	Mar. 07, 2014 Unsecured Debt [Member] 2018 [Member]	Mar. 31, 2014 Unsecured Debt [Member] 2022 [Member]	Mar. 31, 2014 Other Debt Obligations [Member]	Mar. 31, 2014 Debt classified as long-term [Member]	Apr. 19, 2014 Senior Unsecured Debt Due 2018 [Member]	Mar. 07, 2014 Senior Unsecured Debt Due 2018 [Member]	Mar. 31, 2014 8.875% [Member] Unsecured Debt [Member] 2018 [Member]	Mar. 31, 2014 2.7% [Member] Unsecured Debt [Member] 2019 [Member]	Mar. 31, 2014 7.125% [Member] Unsecured Debt [Member] 2022 [Member]	Mar. 31, 2014 4.4% [Member] Unsecured Debt [Member] 2024 [Member]	Mar. 31, 2014 5.6% [Member] Unsecured Debt [Member] 2044 [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 1,732,500,000		$ 0	$ 103,500,000			$ 15,000,000
Senior Notes						226,000,000					198,200,000	397,000,000	225,800,000	446,300,000	346,700,000
Current portion of long-term debt	(198,200,000)	0
Debt classified as long-term	1,534,300,000	0						1,534,300,000
EuroDollar Rate Letter of Credit			3.50%	4.00%
Debt Instrument, Remaining Redemption, Date									Apr. 18, 2014
Debt Instrument, Interest Rate, Stated Percentage										8.875%	8.875%	2.70%	7.125%	4.40%	5.60%
Debt Instrument, Unamortized Discount (Premium), Net	$ 3,300,000				$ (36,300,000)	$ (29,500,000)					$ (9,300,000)	$ 3,000,000	$ (29,200,000)	$ 3,700,000