Net (Loss) Income Per Common Share - Reconciliation of Net Income (Loss) Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Share [Abstract]
Net (loss) income attributable to Earthstone Energy, Inc.	$ (8,871)	$ (16,339)	$ (14,704)	$ 369
Net (loss) income per common share attributable to Earthstone Energy, Inc.:
Basic (in dollars per share)	$ (0.20)	$ (0.55)	$ (0.34)	$ 0.01
Diluted (in dollars per share)	$ (0.20)	$ (0.55)	$ (0.34)	$ 0.01
Weighted average common shares outstanding
Basic (in shares)	44,127,718	29,858,162	43,457,043	29,677,795
Add potentially dilutive securities:
Unvested restricted stock units (in shares)	0	0	0	0
Unvested performance units (in shares)	0	0	0	0
Diluted weighted average common shares outstanding (in shares)	44,127,718	29,858,162	43,457,043	29,677,795