Net Income (Loss) 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, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
Net income (loss) attributable to Earthstone Energy, Inc.	$ 650	$ (17,123)	$ 5,971	$ (16,394)
Net income (loss) per common share attributable to Earthstone Energy, Inc.:
Basic (in dollars per share)	$ 0.02	$ (0.75)	$ 0.21	$ (0.73)
Diluted (in dollars per share)	$ 0.02	$ (0.75)	$ 0.21	$ (0.73)
Weighted average common shares outstanding
Basic (in shares)	27,987,509	22,728,011	27,886,220	22,503,750
Add potentially dilutive securities:
Unvested restricted stock units (in shares)	48,543	0	81,201	0
Diluted weighted average common shares outstanding (in shares)	28,036,052	22,728,011	27,967,421	22,503,750