Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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Balance Type:	debit
Period Type:	duration

- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

This element represents movements included in the statement of changes in partners' capital which are not separately disclosed or provided for elsewhere in the taxonomy.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Per share weighted average intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

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Equity-Based Compensation - Additional Information (details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Phantom units vesting period	3 years
Partners' capital adjustment	$ 792,000us-gaap_PartnersCapitalOther	$ 381,000us-gaap_PartnersCapitalOther	$ 2,528,000us-gaap_PartnersCapitalOther
Weighted-average intrinsic per-unit value	$ 43.10	$ 39.19	$ 0.00
Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense			68,800,000
Unit Value Right [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average intrinsic per-unit value			$ 65.24
Unit Appreciation Right [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average intrinsic per-unit value			$ 2,690.47
Unit Appreciation Right [Member] \| Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
UAR and DER valuation			$ 2,745.00
Distribution Equivalent Right [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average intrinsic per-unit value			$ 11.93
Distribution Equivalent Right [Member] \| Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
UAR and DER valuation			$ 12.00
Independent Director [Member] \| Western Gas Equity Partners Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Phantom units vesting period	1 year
Equity-based compensation expense	200,000	300,000
Unvested equity-based compensation expense	100,000
Weighted-average term of unvested awards	4 months 24 days
Western Gas Partners [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average intrinsic per-unit value	$ 60.74	$ 49.47	$ 41.77	$ 33.92
Western Gas Partners [Member] \| Western Gas Partners Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Phantom units vesting period	3 years
Equity-based compensation expense	600,000	600,000	400,000
Unvested equity-based compensation expense	200,000
Weighted-average term of unvested awards	8 months 12 days
Western Gas Partners [Member] \| Anadarko Incentive Plans [Member] \| Western Gas Equity Partners Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense	3,500,000	3,000,000	3,300,000
Unvested equity-based compensation expense	7,200,000
Weighted-average term of unvested awards	2 years 1 month 6 days
Partners' capital adjustment	3,200,000	2,900,000	3,200,000
Western Gas Partners [Member] \| Independent Director [Member] \| Western Gas Partners Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Phantom units vesting period	1 year
Western Gas Partners [Member] \| Anadarko [Member] \| Western Gas Partners Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested equity-based compensation expense	$ 300,000