Charges.

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Impairment charges.

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Repurchase senior notes.

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Restructuring charges pretax.

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Restructuring charges tax.

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Summary of charges and credit.

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The charge against earnings resulting from the aggregate write down of all assets from their carrying value to their fair value.

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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-Name Accounting Principles Board Opinion (APB)

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Interest rate stated in the contractual debt agreement.

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-Name Regulation S-X (SX)

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-Section 02

-Paragraph 22

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest).

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Charges and Credits (Details 1) (USD $) In Millions, unless otherwise specified	9 Months Ended			3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended		3 Months Ended	9 Months Ended	3 Months Ended				9 Months Ended		3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010	Sep. 30, 2010 Acquisition [Member]	Sep. 30, 2010 Acquisition [Member]	Sep. 30, 2010 Employee Severance [Member]	Sep. 30, 2010 Employee Severance [Member]	Sep. 30, 2010 WesternGeco First Generation Land Operation [Member]	Mar. 31, 2010 Medicare Part D Subsidy [Member]	Sep. 30, 2010 Medicare Part D Subsidy [Member]	Sep. 30, 2011 Merger and integration-related transaction costs	Jun. 30, 2011 Merger and integration-related transaction costs	Mar. 31, 2011 Merger and integration-related transaction costs	Mar. 31, 2010 Merger and integration-related transaction costs	Sep. 30, 2011 Merger and integration-related transaction costs	Sep. 30, 2010 Merger and integration-related transaction costs	Jun. 30, 2011 General and Administrative [Member]	Sep. 30, 2010 Westerngeco Electromagnetic Service [Member]	Sep. 30, 2010 Other Charges on Restructuring [Member]	Sep. 30, 2010 Other Charges on Restructuring [Member]	Sep. 30, 2010 Mexico Restructuring Charges [Member]	Sep. 30, 2010 Mexico Restructuring Charges [Member]	Sep. 30, 2010 Repurchase of Bonds [Member]	Sep. 30, 2010 Repurchase of Bonds [Member]	Sep. 30, 2010 Impairment in Value of Asset [Member]	Sep. 30, 2010 Impairment in Value of Asset [Member]	Sep. 30, 2010 Merger Related Employee Benefits [Member]	Sep. 30, 2010 Merger Related Employee Benefits [Member]	Sep. 30, 2010 Inventory Fair Value Adjustments [Member]	Sep. 30, 2010 Inventory Fair Value Adjustments [Member]	Sep. 30, 2010 Professional Fees [Member]	Sep. 30, 2010 Professional Fees [Member]	Sep. 30, 2010 Restructuring Charges [Member]	Sep. 30, 2010 Restructuring Charges [Member]	Sep. 30, 2010 Gain on Purchase of Business [Member]	Sep. 30, 2010 Gain on Purchase of Business [Member]	Sep. 30, 2010 Notes 6.50 % Due 2012 [Member]	Sep. 30, 2010 M-I SWACO [Member]
Restructuring Charges [Abstract]
Charges Pretax	$ 143			$ (836)	$ (801)	$ 90	$ 90				$ 27	$ 32	$ 34	$ 35	$ 93	$ 56	$ 50		$ 63	$ 63	$ 40	$ 40	$ 28	$ 28	$ 78	$ 78	$ 41	$ 76	$ 38	$ 38	$ 56	$ 56	$ 434	$ 469	$ (1,270)	$ (1,270)	$ 28	$ 1,270
Charges, tax	27			23	(17)	13	13			(40)					17						4	4	10	10	7	7	6	6	14	14	1	1	55	55	(32)	(32)		1,240
Charges	116			(859)	(784)	77	77		40	40	23	24	28		76	55	40	63	63	63	36	36	18	18	71	71	35	70	24	24	55	55	379	414	(1,238)	(1,238)	18
Summary Of Charges And Credit (Textual) [Abstract]
Charges Pretax	143			(836)	(801)	90	90				27	32	34	35	93	56	50		63	63	40	40	28	28	78	78	41	76	38	38	56	56	434	469	(1,270)	(1,270)	28	1,270
Charges	116			(859)	(784)	77	77		40	40	23	24	28		76	55	40	63	63	63	36	36	18	18	71	71	35	70	24	24	55	55	379	414	(1,238)	(1,238)	18
Impairment charges								71
Asset Impairment Charges								78
Equity Method Investment, Other than Temporary Impairment		30
Repurchase Senior Notes																																					352
Noncontrolling interests	123		218
Percentage of equity interest in joint venture																																						40.00%
Guaranteed notes face amount																																					$ 650
Debt instrument interest rate																																					6.50%