Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Numerator:
Net income attributable to Cactus Inc.	$ 12,617	$ 6,233	$ 34,569	$ 31,244
Net income attributable to non-controlling interest	3,400	3,522	9,491	17,271
Net income attributable to Cactus Inc. - diluted	$ 16,017	$ 9,755	$ 44,060	$ 48,515
Denominator:
Effect of dilutive shares (in shares)	17,834	28,112	21,857	28,021
Corporate effective income tax rate, if-converted method	28.00%	25.50%	28.00%	25.50%
Class A Common Stock
Denominator:
Weighted average Class A Shares Outstanding - basic (in shares)	58,248	47,510	54,188	47,406
Weighted average Class A shares outstanding - diluted (in shares)	76,082	75,622	76,045	75,427
Earnings per Class A share - basic (in dollars per share)	$ 0.22	$ 0.13	$ 0.64	$ 0.66
Earnings per Class A share - diluted (in dollars per share)	$ 0.21	$ 0.13	$ 0.58	$ 0.64
Class B Common Stock
Denominator:
Effect of dilutive shares (in shares)	17,800	28,100	21,900	28,000