Number of equal vesting installments.

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- Definition

Performance share awards percentage.

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

+ References

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- Definition

Description of service or performance condition required to be met for earning right to award under share-based payment arrangement. Includes, but is not limited to, combination of market, performance or service condition.

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-SubTopic 10
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-Subparagraph (a)(1)
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- Definition

Description of terms of share-based payment arrangement. Includes, but is not limited to, type of award or grantee and reason for issuance.

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-Publisher FASB
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- 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.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Subparagraph (a)(3)
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Period Type:	instant

- Definition

Gross number of share options (or share units) granted during the period.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
-Subparagraph (d)(1)
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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Stock-Based Compensation - Additional Information (Detail)		3 Months Ended
	Feb. 23, 2023 $ / shares shares	Mar. 31, 2023 USD ($) Installment shares	Mar. 31, 2022 USD ($)
2018 Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense \| $		$ 15,000,000	$ 16,000,000
2018 Plan [Member] \| Stock Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock options granted	1,014,002
Weighted average grant-date fair value of options \| $ / shares	$ 9.75
Weighted average exercise price per share of options \| $ / shares	$ 21.76
2018 Plan [Member] \| Restricted Stock and Restricted Stock Units [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares granted	2,228,226
Restricted stock granted fair value \| $ / shares	$ 21.76
Duration of performance-based restricted stock awards, vested		The restricted stock units vest in three equal annual installments commencing on the first anniversary of the grant date.
Number of equal annual vesting installments \| Installment		3
2018 Plan [Member] \| Performance-base restricted stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Description of performance goal		The 2023 PSAs can be earned based on performance against two established goals over a three-year period
2018 Plan [Member] \| Performance-base restricted stock [Member] \| Minimum [Member] \| Senior Management Employees [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares granted	0
2018 Plan [Member] \| Performance-base restricted stock [Member] \| Maximum [Member] \| Senior Management Employees [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares granted	960,478
2018 Plan [Member] \| TSR Award [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Description of performance goal		85% with a TSR (total shareholder return) goal and 15% with an internal NVA (“NOV Value Added”, a return on capital metric) goal. TSR performance is determined by comparing the Company’s TSR with the TSR of the members of the Philadelphia Stock Exchange’s Oil Services Sector Index (OSX) for the three-year performance period. The TSR portion of the performance share awards is subject to a vesting cap equal to 100% of Target Level if the Company’s absolute TSR is negative, regardless of relative TSR results. Conversely, if the Company’s absolute TSR is greater than 15% annualized over the three-year performance period the payout amount shall not be less than 50% of Target Level, regardless of relative TSR results. The NVA goal is based on the Company’s improvement in NVA from the beginning of the performance period until the end of the performance period. NVA is calculated as an amount equal to the Company’s (a) gross cash earnings less (b) average gross operating assets times an amount equal to a required return on assets, with certain adjustments.
2018 Plan [Member] \| TSR [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Percentage of performance shares awarded		85.00%
2018 Plan [Member] \| NVA [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Percentage of performance shares awarded		15.00%
NOV Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Authorized shares under stock based compensation		55,700,000
Remaining shares available for future grants under the Plan		12,800,000
Income tax benefit recognized \| $		$ 0	$ 0