Equity and Partners' Capital - Additional Information (Details) $ / shares in Units, $ in Thousands		1 Months Ended			3 Months Ended			12 Months Ended
	Mar. 14, 2016 USD ($) $ / shares shares	Apr. 30, 2016 USD ($) shares	Jun. 30, 2015 $ / unit shares	Nov. 30, 2014 USD ($) $ / shares shares	Mar. 31, 2016 USD ($) $ / shares shares	Mar. 31, 2015 USD ($)	[1]	Dec. 31, 2015 USD ($) $ / shares shares	Aug. 31, 2014 USD ($)
Schedule of Investments [Line Items]
Limited partner units owned					218,919,380			218,919,380
Anadarko [Member]
Schedule of Investments [Line Items]
Limited partner units owned					191,087,365
Ownership interest					87.30%
Anadarko [Member] | 7.50% Tangible Equity Units [Member]
Schedule of Investments [Line Items]
Tangible equity units issued			9,200,000
Tangible equity unit rate			7.50%
Stated amount per tangible equity unit | $ / unit			50.00
Debt instrument, maturity date			Jun. 07, 2018
Anadarko [Member] | 7.50% Tangible Equity Units [Member] | Option on Securities [Member]
Schedule of Investments [Line Items]
Tangible equity units issued			1,200,000
Anadarko [Member] | Common Units [Member]
Schedule of Investments [Line Items]
Common units issued			2,300,000
Anadarko [Member] | Common Units [Member] | Option on Securities [Member]
Schedule of Investments [Line Items]
Common units issued			300,000
Public [Member]
Schedule of Investments [Line Items]
Limited partner units owned					27,832,015
Ownership interest					12.70%
Western Gas Partners, LP [Member]
Schedule of Investments [Line Items]
General partner units owned					2,583,068
General partner's interest					1.60%			1.80%
Units issued					323,584
Western Gas Partners, LP [Member] | 500 Million COP [Member]
Schedule of Investments [Line Items]
Maximum aggregate principal of common units | $									$ 500,000
Average price per unit | $ / shares								$ 66.61
Net proceeds to WES | $								$ 57,400
Underwriting discount and other offering expenses | $								800
Gross proceeds | $								58,200
Commissions paid | $								$ 600
Western Gas Partners, LP [Member] | Class C Units [Member]
Schedule of Investments [Line Items]
Units issued					323,584
Price per unit | $ / shares				$ 68.72
Proceeds from the issuance of WES units | $				$ 750,000
Western Gas Partners, LP [Member] | Class C Units [Member] | Maximum [Member]
Schedule of Investments [Line Items]
Redeemable option on units | $				$ 150,000
Western Gas Partners, LP [Member] | Series A Preferred Units [Member]
Schedule of Investments [Line Items]
Limited partner units owned					14,030,611
Price per unit | $ / shares	$ 32.00
Proceeds from the issuance of WES units | $	$ 440,000				$ 440,000	$ 0
Transaction fee	2.00%
Series A Preferred units, units issued upon conversion					1
Minimum common unit closing price for conversion | $ / shares					$ 48.00
Redemption price per unit | $ / shares					$ 32.32
Western Gas Partners, LP [Member] | Series A Preferred Units [Member] | Subsequent Event [Member]
Schedule of Investments [Line Items]
Proceeds from the issuance of WES units | $		$ 247,500
Western Gas Partners, LP [Member] | Common Units [Member]
Schedule of Investments [Line Items]
Limited partner units owned					50,132,046
Ownership interest					31.50%			34.60%
Western Gas Partners, LP [Member] | Common Units [Member] | 500 Million COP [Member]
Schedule of Investments [Line Items]
Common units issued					0			873,525
Western Gas Partners, LP [Member] | Incentive Distribution Rights [Member]
Schedule of Investments [Line Items]
General partner's interest					100.00%			100.00%
Western Gas Partners, LP [Member] | Private investor [Member] | Series A Preferred Units [Member]
Schedule of Investments [Line Items]
Limited partner units owned					14,030,611
Ownership interest					8.80%
Units issued	14,030,611
Western Gas Partners, LP [Member] | Private investor [Member] | Series A Preferred Units [Member] | Subsequent Event [Member] | Option on Securities [Member]
Schedule of Investments [Line Items]
Units issued		7,892,220
Western Gas Partners, LP [Member] | Public [Member] | Common Units [Member]
Schedule of Investments [Line Items]
Limited partner units owned					78,523,141
Ownership interest					49.40%			55.10%
Western Gas Partners, LP [Member] | Other Subsidiaries Of Anadarko [Member]
Schedule of Investments [Line Items]
Ownership interest								8.50%
Western Gas Partners, LP [Member] | Other Subsidiaries Of Anadarko [Member] | Class C Units [Member]
Schedule of Investments [Line Items]
Limited partner units owned					11,735,446
Units issued				10,913,853
Western Gas Partners, LP [Member] | Other Subsidiaries Of Anadarko [Member] | Common Units [Member]
Schedule of Investments [Line Items]
Limited partner units owned					2,011,380
Western Gas Partners, LP [Member] | Other Subsidiaries Of Anadarko [Member] | Common and Class C Units [Member]
Schedule of Investments [Line Items]
Ownership interest					8.70%

[1] Financial information has been recast to include the financial position and results attributable to the Springfield system. See Note 1 and Note 2.