Decrease in noncontrolling interest related to purchase of subsidiary shares, including other transfers from noncontrolling interest.

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The ownership percent of the subsidiary held by the entity before the transaction.

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- Definition

This element represents the total net income attributable to the parent for the period and the effect of net changes during the period impacting the parent's ownership interest in a subsidiary as it relates to the total (consolidated) equity attributable to the parent. The changes to the parent's ownership interest in a subsidiary represented by this element did not result in a deconsolidation of the subsidiary from the consolidated financial statements.

+ References

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

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-Paragraph A7

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The increase (decrease) during the period impacting the parent's ownership interest in a subsidiary as it relates to the total (consolidated) equity attributable to the parent. The changes to the parent's ownership interest in a subsidiary represented by this element did not arise in a deconsolidation of the subsidiary from the consolidated financial statements.

+ References

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- Definition

Represents an increase in noncontrolling interest from issuance of additional equity interests to noncontrolling interest holders or the sale of a portion of the parent's controlling interest.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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- Definition

Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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The value of the noncash (or part noncash) consideration given (for example, liability, equity) in a transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of a transaction not resulting in cash receipts or cash payments in the period.

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The cash outflow associated with the purchase of noncontrolling interest during the period.

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Supplemental Equity and Comprehensive Income Information (Details 6) In Millions, unless otherwise specified	3 Months Ended					9 Months Ended		6 Months Ended
	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Jun. 30, 2010 USD ($)	Mar. 31, 2010 USD ($)	Mar. 31, 2010 JPY (¥)	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Dec. 31, 2009 Sumitomo 3M Limited USD ($)	Mar. 31, 2010 Sumitomo 3M Limited
Transactions with Sumitomo 3M
3M's effective ownership before transaction (as a percent)								75.00%	71.50%
3M's effective ownership after transaction (as a percent)								71.50%	75.00%
Increase in noncontrolling interest								$ 81
Cash paid to acquire additional shares				63	5,800
Note payable issued to Sumitomo Electric Industries				188	17,400
Purchase of subsidiary shares including other transfers from noncontrolling interest				278
Net income attributable to 3M	1,088	1,106				3,329	3,157
Transfer from noncontrolling interest			24	22			46
Change in 3M Company shareholders' equity from net income attributable to 3M and transfers from noncontrolling interest							$ 3,203