Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fixed charge coverage ratio to be maintained under the debt instrument agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	whd_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

The contingent increase above the maximum borrowing capacity under the credit facility, if any one or more of the existing banks or new banks agree to provide such increased commitment amount.

+ References

No definition available.

+ Details

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Namespace Prefix:	whd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The aggregate borrowing capacity under the credit facility, consisting of the maximum borrowing capacity plus the contingent increase, if any one or more of the existing banks or new banks agree to provide such increased commitment amount.

+ References

No definition available.

+ Details

Name:	whd_LineOfCreditFacilityContingentIncreaseAggregateMaximumBorrowingCapacity
Namespace Prefix:	whd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=whd_PriorRevolvingCreditFacilityMember
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- Details

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- Details

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Long-term Debt - Credit agreement (Details) - USD ($) $ in Millions			9 Months Ended
	Aug. 21, 2018	Feb. 12, 2018	Sep. 30, 2018	Dec. 31, 2017	Jul. 31, 2014
Long-term Debt
Applicable margin rate (as a percent)		1.50%
Eurodollar
Long-term Debt
Applicable margin rate (as a percent)			1.50%
Prior Credit Agreement
Long-term Debt
Amount outstanding				$ 248.5	$ 0.0
Weighted average interest rate				7.30%
Prior Revolving Credit Facility
Long-term Debt
Amount outstanding			$ 0.0
Revolving Loans \| Prior Revolving Credit Facility
Long-term Debt
Maximum borrowing capacity					50.0
Letters of credit
Long-term Debt
Letters of credit outstanding			0.0
Letters of credit \| Prior Revolving Credit Facility
Long-term Debt
Maximum borrowing capacity					10.0
ABL Credit Facility
Long-term Debt
Amount outstanding			$ 0.0
Cactus LLC \| Prior Credit Agreement
Long-term Debt
Face amount					$ 275.0
Cactus LLC \| Letters of credit
Long-term Debt
Maximum borrowing capacity	$ 15.0
Cactus LLC \| ABL Credit Facility
Long-term Debt
Debt term	5 years
Maximum borrowing capacity	$ 75.0
Amount not exceed for additional revolving commitments	50.0
Total of revolving commitments	$ 125.0
Fixed charge coverage ratio			1.0
Cactus LLC \| ABL Credit Facility \| Minimum
Long-term Debt
Commitment fee (as a percent)			0.25%
Cactus LLC \| ABL Credit Facility \| Minimum \| Base Rate
Long-term Debt
Applicable margin rate (as a percent)			0.50%
Cactus LLC \| ABL Credit Facility \| Minimum \| Eurodollar
Long-term Debt
Applicable margin rate (as a percent)			1.50%
Cactus LLC \| ABL Credit Facility \| Maximum
Long-term Debt
Commitment fee (as a percent)			0.375%
Cactus LLC \| ABL Credit Facility \| Maximum \| Base Rate
Long-term Debt
Applicable margin rate (as a percent)			1.00%
Cactus LLC \| ABL Credit Facility \| Maximum \| Eurodollar
Long-term Debt
Applicable margin rate (as a percent)			2.00%