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.

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-Name Accounting Standards Codification
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- Definition

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

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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- Definition

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

+ References

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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).

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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).

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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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- 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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- Definition

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

+ References

No definition available.

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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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Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Stock-Based Compensation - Additional Information (Detail)		3 Months Ended
	Feb. 15, 2022 Installment $ / shares shares	Mar. 31, 2022 USD ($) shares	Mar. 31, 2021 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted	1,492,020
Stock options fair value \| $ / shares	$ 6.28
Stock options exercise price \| $ / shares	$ 16.73
Restricted Stock and Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	2,877,894
Restricted stock granted fair value \| $ / shares	$ 16.73
Number of equal annual vesting installments \| Installment	3
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.
Performance-base restricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Description of performance goal		The 2022 PSAs can be earned based on performance against two established goals over a three-year period:
Performance-base restricted stock [Member] \| Senior Management Employees [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	0
Performance-base restricted stock [Member] \| Senior Management Employees [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	1,188,884
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
TSR [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of Performance Shares Awarded		85.00%
NVA [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of Performance Shares Awarded		15.00%
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.
2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized shares under stock based compensation		42,700,000
Remaining shares available for future grants under the Plan		4,100,000
Stock-based compensation expense \| $		$ 16,000,000	$ 20,000,000
Income tax benefit recognized \| $		$ 0	$ 0