Organization and Nature of Operations (Details) $ / shares in Units, $ in Thousands				6 Months Ended	12 Months Ended
	Jul. 16, 2018 $ / shares shares	Feb. 14, 2018 USD ($) shares	Feb. 12, 2018 USD ($) Vote item $ / shares shares	Jun. 30, 2018 USD ($) Center $ / shares shares	Dec. 31, 2017 USD ($)	Feb. 11, 2018 shares
Organization and Nature of Operations
Number of U.S. service centers | Center				15
Number of service centers in Australia | Center				1
Net proceeds from IPO | $				$ 469,621
Offering costs | $			$ 2,800		$ 2,200
Number of shares canceled | shares		3,450,000
Write off of stock issuance costs against equity | $			$ 2,200
Restricted stock unit awards issued (in shares) | shares			737,493
Deferred tax asset, net | $			$ 74,100	70,307
Liability related to tax receivable agreement | $			63,000	62,989
Additional paid-in capital related to tax receivable agreement | $			11,100	11,116
Retained earnings | $				$ 16,087
Non-controlling interest | $			130,900
Cactus LLC
Organization and Nature of Operations
Net proceeds from IPO | $			469,600
Retained earnings | $			0
Cactus LLC | Term loan facility
Organization and Nature of Operations
Repayments of debt | $			$ 251,000
Cactus LLC
Organization and Nature of Operations
Ownership interest	50.30%			35.30%
Members' Equity (Deficit) | Cactus LLC
Organization and Nature of Operations
Redeem CW Units from certain direct and indirect owners (in units) | shares			8,667,841
Redeem CW Units from certain direct and indirect owners | $			$ 216,400
Class A Common Stock
Organization and Nature of Operations
Common stock, par value | $ / shares				$ 0.01
Common stock, shares issued | shares	37,646,562			26,450,000
Common stock, shares outstanding | shares	37,646,562			26,450,000		0
Class B Common Stock
Organization and Nature of Operations
Number of shares issued | shares			51,889,772
Common stock, par value | $ / shares			$ 0.01	$ 0.01
Number of votes per holder | Vote			1
Common stock, shares issued | shares	37,243,210			48,439,772
Common stock, shares outstanding | shares	37,243,210			48,439,772		0
Class B Common Stock | Cactus LLC
Organization and Nature of Operations
Redeem CW Units from certain direct and indirect owners (in units) | shares		3,450,000
Class B Common Stock | Members' Equity (Deficit) | Cactus LLC
Organization and Nature of Operations
Number of common stock for each unit | item			1
IPO | Members' Equity (Deficit)
Organization and Nature of Operations
Number of CW Units acquired with the proceeds from the sale of common stock | shares			23,000,000
IPO | Class A Common Stock
Organization and Nature of Operations
Number of shares issued | shares			23,000,000
Common stock, par value | $ / shares			$ 0.01
Price per share | $ / shares			$ 19.00
Net proceeds from IPO | $			$ 408,000
Underwriter's option | Members' Equity (Deficit)
Organization and Nature of Operations
Number of CW Units acquired with the proceeds from the sale of common stock | shares		3,450,000
Underwriter's option | Class A Common Stock
Organization and Nature of Operations
Number of shares issued | shares		3,450,000
Net proceeds from IPO | $		$ 61,600
Follow On Offering | Class A Common Stock
Organization and Nature of Operations
Number of shares issued | shares	11,196,562
Price per share | $ / shares	$ 33.25