Significant Accounting Policies (Detail 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2010 years number	Dec. 31, 2009	Dec. 31, 2008
Significant Accounting Policies
Asset retirement obligation liability	$ 74	$ 64
Intangible assets useful life, low end of range (in years)	1
Intangible assets useful life, high end of range (in years)	20
Advertising and merchandising expense	512	414	468
Research, development and related expenses	1,434	1,293	1,404
Research and development expense	919	838	851
Deferred tax assets valuation allowance	$ 128	$ 23

The high end of the range of the useful life of finite-lived intangible assets.

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- Definition

The low end of the range of the useful life of finite-lived intangible assets.

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- Definition

The aggregate costs incurred during an accounting period to research and develop new products/technologies when the technological feasibility has not been reached, and related expenses, which primarily include technical support provided by 3M to customers who are using existing 3M products; internally developed patent costs, which include costs and fees incurred to prepare, file, secure and maintain patents; and amortization of acquired patents.

+ Details

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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 93-7

+ Details

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 143
-Paragraph 3, 10, 22

+ Details

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- Definition

The sum of the portions of deferred tax assets as of the balance sheet date for which, based on the weight of available evidence, it is more likely than not will not be realized through future reductions of tax-based income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 17
-Subparagraph e

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 43-49

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- Definition

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph g

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 2
-Paragraph 12, 13

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 86
-Paragraph 11, 12

+ Details

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