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Equity-Based Compensation - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Mar. 22, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of units vested	$ 8.5	$ 0.5	$ 1.2
Unvested equity-based compensation expense	$ 27.4
Weighted-average term of unvested awards	1 year 1 month 6 days
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation - payout percentage	0.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation - payout percentage	200.00%
Western Gas Equity Partners 2012 Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units authorized under LTIP	3,000,000
Units available under LTIP	484,909
Western Gas Partners 2017 Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units authorized under LTIP	3,431,251
Units available under LTIP	2,308,578
Western Midstream Partners, LP 2021 Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units authorized under LTIP	9,500,000			9,500,000
Units available under LTIP	9,500,000
Executive Long-Term Incentive Plans [Member] \| Time-vested Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units vesting period	3 years
Executive Long-Term Incentive Plans [Member] \| TUR Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units vesting period	3 years
Executive Long-Term Incentive Plans [Member] \| ROA Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units vesting period	3 years
Long-Term Incentive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
In-kind distributions issued, number of units	21,681	48,070
Equity-based compensation expense	$ 17.6	$ 7.9	$ 1.0
Non-Executive Long-Term Incentive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units vesting period	3 years
Independent Director Long-Term Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units vesting period	1 year