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Equity-Based Compensation - WES LTIP Award Activity Table (details) (Western Gas Partners [Member], USD $)
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Western Gas Partners [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Units outstanding at beginning of year 25,619 23,978 17,503  
Vested (14,695) (14,260) (15,119)  
Granted 5,920 15,901 21,594  
Units outstanding at end of year 16,844 25,619 23,978  
Value per unit of phantom units outstanding $ 49.47 $ 41.77 $ 33.92 $ 20.19
Value per unit of phantom units vested during the period $ 41.28 $ 33.20 $ 20.51  
Value per unit of phantom units granted during the period $ 62.49 $ 45.91 $ 35.66