Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Consolidated Statement of Comprehensive Income
Net income including noncontrolling interest	$ 5,363	$ 4,869	$ 5,058
Other comprehensive income (loss), net of tax:
Cumulative translation adjustment	(467)	373	(331)
Defined benefit pension and postretirement plans adjustment	444	52	(524)
Cash flow hedging instruments - unrealized gain (loss)	176	(203)	(33)
Total other comprehensive income (loss), net of tax	153	222	(888)
Comprehensive income (loss) including noncontrolling interest	5,516	5,091	4,170
Comprehensive (income) loss attributable to noncontrolling interest	(8)	(14)	(6)
Comprehensive income (loss) attributable to 3M	$ 5,508	$ 5,077	$ 4,164

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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