INVESTMENTS - AllDale (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Changes in equity method investment
Beginning balance	$ 28,529
Equity method investment income (loss)	451	$ 324
Ending balance	28,114
All Dale Minerals III
Changes in equity method investment
Beginning balance	28,529	28,974
Equity method investment income (loss)	451	324
Distributions received	(593)	(528)
Other	(273)
Ending balance	$ 28,114	$ 28,770

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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