Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Numerator:
Net income attributable to Cactus Inc.	$ 18,983	$ 26,807
Net income attributable to non-controlling interest (1)	11,166	17,505
Net income attributable to Cactus Inc. - diluted (1)	$ 30,149	$ 44,312
Denominator:
Effect of dilutive shares (2)	28,125	36,527
After-tax income attributable to non-controlling interest	$ 11,200	$ 17,500
Corporate effective interest rate, if-converted method	26.00%	24.00%
Class A Common Stock
Denominator:
Weighted average Class A Shares Outstanding - basic	47,270	38,719
Weighted average Class A Shares Outstanding - diluted (2)	75,395	75,246
Earnings per Class A share - basic	$ 0.40	$ 0.69
Earnings per Class A Share - diluted (1) (2)	$ 0.40	$ 0.59
Class B Common Stock
Denominator:
Effect of dilutive shares (2)	28,000	36,300

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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