FAIR VALUE MEASUREMENTS (Notes)	12 Months Ended
FAIR VALUE MEASUREMENTS (Notes)	Dec. 31, 2019
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS The Company’s financial assets and liabilities measured at fair value on a recurring basis consist of: cash and cash equivalents; revenue receivables; accounts receivable from/payable to Apache and an embedded derivative liability related to the issuance of Preferred Units (as further described above). This embedded derivative liability is recorded on the Company’s consolidated balance sheet at fair value. The carrying amount of Altus Midstream’s revolving credit facility approximates fair value because the interest rate is variable and reflective of market rates. The carrying amounts reported on the consolidated balance sheet for the Company’s remaining financial assets and liabilities approximate fair value due to their short-term nature. There were no transfers between Level 1, Level 2 or Level 3 of the fair value hierarchy during the year ended December 31, 2019 or December 31, 2018. The Company bifurcated and recognized the embedded derivative associated with the Preferred Units related to the exchange option provided to the Preferred Unit holders under the terms of the Amended LPA. The valuation of the embedded derivative (using an income approach) was based on a range of factors including expected future interest rates using the Black-Karasinski model, the Company’s imputed interest rate, the timing of periodic cash distributions, and dividend yields of the Preferred Units. The embedded derivative liability had an initial fair value of $94.5 million at Closing. For the year ended December 31, 2019, the Company recorded an unrealized loss related to this derivative liability totaling $8.5 million, which is recorded in “Unrealized derivative instrument loss” in the statement of consolidated operations. Increases or decreases in interest rates would result in a higher or lower fair value measurement. The Company has additional embedded derivatives in the Preferred Units related to the exchange option and redemption features that are accounted for separately from the Preferred Units. Level 3 valuation of the embedded derivatives are based on a range of factors including the likelihood of the event occurring, and these factors are assessed quarterly. There was no value associated with these additional identified embedded derivatives for any applicable period presented.

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.