Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2018	Jan. 31, 2019	Jun. 30, 2018
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Trading Symbol	ALTM
Entity Registrant Name	Altus Midstream Company
Entity Central Index Key	0001692787
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Non-accelerated Filer
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Small Business	false
Entity Shell Company	false
Entity Public Float			$ 392,413,965
Class A Common Stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		74,929,305
Class C Common Stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		250,000,000