Goodwill and Other Intangible Assets (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Acquired Finite-Lived Intangible Assets [Line Items]
Other intangible assets	$ 174,838	$ 7,585
Crude [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Other intangible assets	5,775	0
SemGas [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Other intangible assets	163,144	0
SemMexico [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Other intangible assets	5,888	7,549
Corporate and other [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Other intangible assets	$ 31	$ 36