FAIR VALUE MEASUREMENTS - Nonrecurring Measurements (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
5.625% Senior Notes due 2025
Fair value of assets and liabilities measured on a recurring and nonrecurring basis
Interest rate	5.625%
Reported Value Measurement \| 5.625% Senior Notes due 2025 \| Nonrecurring
Fair value of assets and liabilities measured on a recurring and nonrecurring basis
Senior notes due	$ 490,454	$ 0
Reported Value Measurement \| Rattler Credit Facility \| Nonrecurring
Fair value of assets and liabilities measured on a recurring and nonrecurring basis
Revolving credit facility	85,000	424,000
Estimate of Fair Value Measurement \| 5.625% Senior Notes due 2025 \| Nonrecurring
Fair value of assets and liabilities measured on a recurring and nonrecurring basis
Senior notes due	504,605	0
Estimate of Fair Value Measurement \| Rattler Credit Facility \| Nonrecurring
Fair value of assets and liabilities measured on a recurring and nonrecurring basis
Revolving credit facility	$ 85,000	$ 424,000

Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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