Preparation of Interim Financial Statements and Other Items - Provision for Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Other Ownership Interests [Line Items]
Non-controlling interest owned (as a percentage)	64.70%
Current:
Federal	$ 211
State	240
Foreign	238
Total current income taxes	689
Deferred:
Federal	762
State	128
Foreign	73
Total deferred income taxes	963	$ 29
Total provision for income taxes	$ 1,652	$ 154
Cactus LLC
Other Ownership Interests [Line Items]
Ownership interest (as a percent)	35.30%