Income Taxes - Deferred tax (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Components of deferred tax assets and liabilities
Investment in Cactus LLC	$ 234,629	$ 181,390
Net operating loss carryforwards		619
Imputed interest	10,323	7,445
Tax credits	1,479	1,988
Other	155	144
Deferred tax assets	246,586	191,586
Valuation allowance	(24,041)	(32,533)
Deferred tax asset, net	222,545	159,053
Foreign withholding taxes	1,054	1,036
Other	294
Deferred tax liability, net	$ 1,348	$ 1,036

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