Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Business Segments and Geographic Areas - Business Segments (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Revenues	$ 5,709us-gaap_SalesRevenueNet	$ 5,587us-gaap_SalesRevenueNet	$ 5,255us-gaap_SalesRevenueNet	$ 4,889us-gaap_SalesRevenueNet	$ 5,302us-gaap_SalesRevenueNet	$ 4,863us-gaap_SalesRevenueNet	$ 4,680us-gaap_SalesRevenueNet	$ 4,376us-gaap_SalesRevenueNet	$ 21,440us-gaap_SalesRevenueNet	$ 19,221us-gaap_SalesRevenueNet	$ 17,194us-gaap_SalesRevenueNet
Operating profit									3,613us-gaap_OperatingIncomeLoss	3,199us-gaap_OperatingIncomeLoss	3,389us-gaap_OperatingIncomeLoss
Capital expenditures									699	614	569
Depreciation and amortization									778us-gaap_DepreciationAndAmortization	738us-gaap_DepreciationAndAmortization	616us-gaap_DepreciationAndAmortization
Goodwill	8,539us-gaap_Goodwill				9,049us-gaap_Goodwill				8,539us-gaap_Goodwill	9,049us-gaap_Goodwill	7,172us-gaap_Goodwill
Total assets	33,562us-gaap_Assets				34,812us-gaap_Assets				33,562us-gaap_Assets	34,812us-gaap_Assets	31,484us-gaap_Assets
Rig Systems [Member]
Segment Reporting Information [Line Items]
Goodwill	1,236				1,279				1,236	1,279	1,097
Rig Aftermarket [Member]
Segment Reporting Information [Line Items]
Goodwill	877				906				877	906	649
Wellbore Technologies [Member]
Segment Reporting Information [Line Items]
Goodwill	4,357				4,425				4,357	4,425	3,769
Completion & Production Solutions [Member]
Segment Reporting Information [Line Items]
Goodwill	2,069				2,106				2,069	2,106	1,314
Operating Segments [Member] \| Rig Systems [Member]
Segment Reporting Information [Line Items]
Revenues									9,848	8,450	7,077
Operating profit									1,996	1,594	1,685
Capital expenditures									133	61	81
Depreciation and amortization									88	82	64
Goodwill	1,237				1,279				1,237	1,279	1,097
Total assets	8,052				7,654				8,052	7,654	6,563
Operating Segments [Member] \| Rig Aftermarket [Member]
Segment Reporting Information [Line Items]
Revenues									3,222	2,692	2,138
Operating profit									882	729	594
Capital expenditures									12	24	13
Depreciation and amortization									27	26	18
Goodwill	878				906				878	906	649
Total assets	2,789				2,475				2,789	2,475	1,930
Operating Segments [Member] \| Wellbore Technologies [Member]
Segment Reporting Information [Line Items]
Revenues									5,722	5,211	5,184
Operating profit									937	915	983
Capital expenditures									262	226	247
Depreciation and amortization									439	420	389
Goodwill	4,357				4,425				4,357	4,425	3,769
Total assets	11,687				11,862				11,687	11,862	11,032
Operating Segments [Member] \| Completion & Production Solutions [Member]
Segment Reporting Information [Line Items]
Revenues									4,645	4,309	3,994
Operating profit									690	613	684
Capital expenditures									184	212	169
Depreciation and amortization									224	210	145
Goodwill	2,067				2,106				2,067	2,106	1,314
Total assets	7,072				7,287				7,072	7,287	6,192
Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues									(1,997)	(1,441)	(1,199)
Operating profit									(892)	(652)	(557)
Capital expenditures									108	91	59
Total assets	3,962				3,351				3,962	3,351	3,394
Discontinued Operations [Member]
Segment Reporting Information [Line Items]
Goodwill					333					333	343
Total assets					$ 2,183					$ 2,183	$ 2,373