Consolidated Statements of Stockholders' Equity (USD $) In Millions, except Share data	Total	Common Stock [Member]	Retained Earnings [Member]	NOV Net Investment [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning balance at Dec. 31, 2011	$ 669			$ 660	$ 9
Net income	108us-gaap_NetIncomeLoss			108
Contributions/transfers from (distributions to) NOV	1,185dnow_NetTransfersFromRelatedParty			1,185
Other comprehensive income (loss)	9				9
Ending balance at Dec. 31, 2012	1,971			1,953	18
Net income	147us-gaap_NetIncomeLoss			147
Contributions/transfers from (distributions to) NOV	(298)dnow_NetTransfersFromRelatedParty			(298)
Other comprehensive income (loss)	(18)				(18)
Ending balance at Dec. 31, 2013	1,802			1,802
Net income	116us-gaap_NetIncomeLoss		58	58
Contributions/transfers from (distributions to) NOV	75dnow_NetTransfersFromRelatedParty			75
Stock-based compensation	18	13		5
Reclassification of NOV net investment to additional paid-in capital		1,940		(1,940)
Issuance of common stock at Separation, value		(1)
Issuance of common stock at the Separation, par value		1
Other comprehensive income (loss)	(45)				(45)
Issuance of common stock at Separation, share		107,053,000
Issuance of common stock for exercise of options		14,000
Ending balance, Common stock value at Dec. 31, 2014	1us-gaap_CommonStockValue	1
Ending balance at Dec. 31, 2014	$ 1,966	$ 1,952	$ 58		$ (45)
Ending balance, shares at Dec. 31, 2014		107,067,000

Issuance Of Common Stock At Spin Off

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Issuance Of Common Stock At The Separation Par Value

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Issuance Of Common Stock Shares In Connection With Acquisition

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Net transfers from related party.

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Reclassification of net parent company investment to additional paid in capital.

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This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Number of shares issued which are neither cancelled nor held in the treasury.

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Number of share options (or share units) exercised during the current period.

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