Cover Page - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2020	Feb. 22, 2021	Jun. 30, 2020
Entity Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity Registrant Name	WESTERN MIDSTREAM PARTNERS, LP
Entity File Number	001-35753
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-0967367
Entity Address, Address Line One	9950 Woodloch Forest Drive, Suite 2800
Entity Address, City or Town	The Woodlands,
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77380
City Area Code	(832)
Local Phone Number	636-1009
Title of 12(b) Security	Common units
Trading Symbol	WES
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 2.0
Entity Common Units Outstanding		413,059,211
Documents Incorporated by Reference	None
Entity Central Index Key	0001423902
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
WES Operating [Member]
Entity Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity Registrant Name	WESTERN MIDSTREAM OPERATING, LP
Entity File Number	001-34046
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-1075808
Entity Address, Address Line One	9950 Woodloch Forest Drive, Suite 2800
Entity Address, City or Town	The Woodlands,
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77380
City Area Code	(832)
Local Phone Number	636-1009
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Documents Incorporated by Reference	None
Entity Central Index Key	0001414475
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31