Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Consolidated Statement of Comprehensive Income
Net income including noncontrolling interest	$ 4,869	$ 5,058	$ 4,841
Other comprehensive income (loss), net of tax:
Cumulative translation adjustment	373	(331)	(586)
Defined benefit pension and postretirement plans adjustment	52	(524)	489
Cash flow hedging instruments - unrealized gain (loss)	(203)	(33)	25
Total other comprehensive income (loss), net of tax	222	(888)	(72)
Comprehensive income (loss) including noncontrolling interest	5,091	4,170	4,769
Comprehensive (income) loss attributable to noncontrolling interest	(14)	(6)	(6)
Comprehensive income (loss) attributable to 3M	$ 5,077	$ 4,164	$ 4,763

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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