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Transactions with Affiliates - LTIP Award Activity Tables (Details) - $ / shares
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Related Party Transaction [Line Items]      
Value per unit of phantom units outstanding at beginning of year $ 43.10 $ 39.19 $ 0.00
Value per unit of phantom units vested during the period 44.44 37.32 0.00
Value per unit of phantom units granted during the period 62.21 51.19 39.19
Value per unit of phantom units outstanding at end of year $ 47.20 $ 43.10 $ 39.19
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]      
Phantom units outstanding at beginning of year 22,236 36,238 0
Phantom units vested (13,317) (18,400) 0
Phantom units granted 3,618 4,398 36,238
Phantom units outstanding at end of year 12,537 22,236 36,238
Western Gas Partners, LP [Member]      
Related Party Transaction [Line Items]      
Value per unit of phantom units outstanding at beginning of year $ 60.74 $ 49.47 $ 41.77
Value per unit of phantom units vested during the period 60.69 49.55 41.28
Value per unit of phantom units granted during the period 69.10 68.14 62.49
Value per unit of phantom units outstanding at end of year $ 68.78 $ 60.74 $ 49.47
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]      
Phantom units outstanding at beginning of year 9,522 16,844 25,619
Phantom units vested (9,257) (13,122) (14,695)
Phantom units granted 5,212 5,800 5,920
Phantom units outstanding at end of year 5,477 9,522 16,844