v3.19.3.a.u2

SIGNIFICANT CONCENTRATIONS (Details) - USD ($) $ in Thousands	1 Months Ended	8 Months Ended	11 Months Ended	12 Months Ended
	Feb. 08, 2018	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2019
Concentration Risk [Line Items]
Revenue marketed by ARM on our behalf	$ 47,639		$ 467,977	$ 489,858
Customer Concentration Risk \| Sales Revenue, Net \| One Customer
Concentration Risk [Line Items]
Percent of operating revenue accounted for by customer				40.50%
AEM
Concentration Risk [Line Items]
Revenue marketed by ARM on our behalf	28,757	$ 336,248		$ 123,000
Amount paid for marketing fees	66	784		496
Total fees paid to ARM	66	784		2,211
Accounts receivable			$ 43,800	6,800
Marketing fees \| AEM
Concentration Risk [Line Items]
Amount paid for marketing fees	$ 0	$ 0		$ 1,715

For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Alta Mesa Resources, Inc. /DE 10-K