Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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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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Amount of cash outflow to a noncontrolling interest. Includes, but not limited to, reduction of noncontrolling interest ownership. Excludes dividends paid to the noncontrolling interest.

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Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

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Supplemental Equity and Comprehensive Income Information - NCI (Details) $ in Millions, ¥ in Billions	1 Months Ended		3 Months Ended	9 Months Ended
	Sep. 30, 2014 JPY (¥)	Sep. 30, 2014 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2014 USD ($)
Transactions with 3M subsidiaries that have non controlling interests
Amount recorded as a financing activity in the statement of cash flows				$ 699
Purchase of remaining noncontrolling interest portion			$ 865	870
Common Stock and Additional Paid-in Capital
Transactions with 3M subsidiaries that have non controlling interests
Purchase of remaining noncontrolling interest portion			433	434
Noncontrolling Interest
Transactions with 3M subsidiaries that have non controlling interests
Purchase of remaining noncontrolling interest portion			$ 457	$ 461
Sumitomo 3M Limited
Transactions with 3M subsidiaries that have non controlling interests
Percent acquired of remaining noncontrolling interest	25.00%	25.00%	25.00%	25.00%
3M's effective ownership after transaction	100.00%	100.00%
Amount recorded as a financing activity in the statement of cash flows		$ 694
Purchase of remaining noncontrolling interest portion	¥ 90	$ 865