Net (Loss) Income per Share - Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net income attributable to Liberty Oilfield Services Inc. Stockholders	$ (34,205)	$ 1,720
Denominator, Basic [Abstract]
Basic weighted average shares outstanding (in shares)	163,207	81,651
Basic net income per share attributable to Liberty Oilfield Services Inc. Stockholders (in dollars per share)	$ (0.21)	$ 0.02
Numerator, Diluted [Abstract]
Net income attributable to Liberty Oilfield Services Inc. Stockholders	$ (34,205)	$ 1,720
Effect of exchange of the shares of Class B Common Stock for shares of Class A Common Stock	0	632
Net Income (Loss) Available to Common Stockholders, Diluted	$ (34,205)	$ 2,352
Denominator, Diluted [Abstract]
Basic weighted average shares outstanding (in shares)	163,207	81,651
Effect of dilutive securities:
Restricted stock (in shares)	0	268
Restricted stock units (in shares)	0	2,394
Class B Common Stock (in shares)	0	30,639
Diluted weighted average shares outstanding (in shares)	163,207	114,952
Diluted net income per share attributable to Liberty Oilfield Services Inc. Stockholders (in dollars per share)	$ (0.21)	$ 0.02