v3.25.4

Common Stock and Stock Compensation - Additional Information (Detail)							12 Months Ended
	May 20, 2025 $ / shares shares	Apr. 28, 2025 $ / shares shares	Mar. 20, 2025 $ / shares shares	Mar. 06, 2025 $ / shares shares	Feb. 19, 2025 $ / shares shares	Dec. 20, 2017 USD ($) $ / shares shares	Dec. 31, 2025 USD ($) $ / shares shares	Dec. 31, 2024 USD ($) Installment $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock, authorized							1,000,000,000	1,000,000,000
Number of preferred stock, authorized							10,000,000
Common stock, par value | $ / shares							$ 0.01	$ 0.01
Preferred stock, par value | $ / shares							$ 0.01
Preferred stock, shares issued							0
Preferred stock, shares outstanding							0
Aggregated cash dividends paid | $							$ 190,000,000	$ 108,000,000	$ 79,000,000
Stock-based compensation expense | $							67,000,000	70,000,000	66,000,000
Income tax benefit (expense) recognized | $							$ (1,000,000)	$ 2,000,000	$ 7,000,000
Earlier authorized shares under stock based compensation | shares							69,400,000
Duration of performance-based restricted stock awards, vested							Options granted under our stock-based compensation plans generally vest over a three-year period starting one year from the date of grant and expire ten years from the date of grant.
Weighted average grant-date fair value of options | $ / shares							$ 6.67	$ 7.9	$ 9.75
Total intrinsic value of options exercised | $							$ 0	$ 1,000,000
Stock option, Minimum Range | $ / shares							$ 15.00
Stock option, Maximum Range | $ / shares							$ 38.86
Weighted-average remaining contractual term for outstanding stock options							3 years 4 months 9 days
Weighted-average remaining contractual term for exercisable stock options							2 years 9 months 14 days
Aggregate intrinsic value of outstanding options | $							$ 0
Total unrecognized compensation cost related to nonvested stock options | $							$ 6,000,000
Compensation cost not yet recognized, period for recognition							3 years
Total fair value of stock options vested | $							$ 9,000,000	9,000,000	$ 9,000,000
Cash received from option exercises | $							0	3,000,000	4,000,000
Actual tax benefit (expense) from share based compensation | $							0	0	$ 0
Cash payment of stock appreciation rights | $							$ 315,000,000	$ 229,000,000
Stock options granted							526,425	1,110,478	1,014,002
Weighted average exercise price per share of options | $ / shares							$ 15.28	$ 17.52	$ 21.76
Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock appreciation rights exchange percentage						94.75%
Cash payment of stock appreciation rights | $						$ 14,000,000
Cash paid to settle SARs | $							$ 0
Compensation cost recognized | $							$ 0	$ 0	$ 0
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant-date fair value of options | $ / shares						$ 8.47
Stock options granted						3,613,707
Weighted average exercise price per share of options | $ / shares						$ 34.32
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration of performance-based restricted stock awards, vested							The RSUs vest in three equal annual installments commencing on the first anniversary of the grant date.
Shares granted			82,781	750	3,214,507
Restricted stock granted fair value | $ / shares			$ 15.1	$ 14.35	$ 15.28
Number of equal annual vesting installments | Installment								3
Restricted Stock Units and Performance Share Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to nonvested stock options | $							$ 68,000,000
Compensation cost not yet recognized, period for recognition							2 years
Shares granted							4,112,266	3,204,434	2,792,465
Restricted stock granted fair value | $ / shares							$ 16.02	$ 17.96	$ 22.70
Performance-base restricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Description of performance goal							The 2025 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		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			152,316		1,217,278
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.On April 28, 2025, the Company granted 1,839 restricted stock units with a fair value of $12.24 per share. The awards were granted to employees and vest in three equal annual installments commencing on the first anniversary of grant date.
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%
2018 Plan [Member] | Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant-date fair value of options | $ / shares					$ 6.67
Stock options granted					526,425
Weighted average exercise price per share of options | $ / shares					$ 15.28
2018 Plan [Member] | Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	127,592	1,839
Restricted stock granted fair value | $ / shares	$ 12.54	$ 12.24
NOV Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized shares under stock based compensation							70,900,000
Remaining shares available for future grants under the Plan							17,200,000

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