Supplemental Equity and Comprehensive Income Information (Tables)

12 Months Ended

Dec. 31, 2017

Supplemental Equity and Comprehensive Income Information

Changes in Accumulated Other Comprehensive Income (Loss) Attributable to 3M

Changes in Accumulated Other Comprehensive Income (Loss) Attributable to 3M by Component

			Defined Benefit		Cash Flow		Total
			Pension and		Hedging		Accumulated
	Cumulative		Postretirement		Instruments,		Other
	Translation		Plans		Unrealized		Comprehensive
(Millions)	Adjustment		Adjustment		Gain (Loss)		Income (Loss)
Balance at December 31, 2014, net of tax:	$	(1,095)	$	(5,293)	$	99	$	(6,289)
Other comprehensive income (loss), before tax:
Amounts before reclassifications		(447)		367		212		132
Amounts reclassified out		—		537		(174)		363
Total other comprehensive income (loss), before tax		(447)		904		38		495
Tax effect		(137)		(415)		(13)		(565)
Total other comprehensive income (loss), net of tax		(584)		489		25		(70)
Balance at December 31, 2015, net of tax:	$	(1,679)	$	(4,804)	$	124	$	(6,359)
Other comprehensive income (loss), before tax:
Amounts before reclassifications		(244)		(1,122)		57		(1,309)
Amounts reclassified out		—		421		(109)		312
Total other comprehensive income (loss), before tax		(244)		(701)		(52)		(997)
Tax effect		(85)		177		19		111
Total other comprehensive income (loss), net of tax		(329)		(524)		(33)		(886)
Balance at December 31, 2016, net of tax:	$	(2,008)	$	(5,328)	$	91	$	(7,245)
Other comprehensive income (loss), before tax:
Amounts before reclassifications		91		(600)		(311)		(820)
Amounts reclassified out		—		483		(7)		476
Total other comprehensive income (loss), before tax		91		(117)		(318)		(344)
Tax effect		279		169		115		563
Total other comprehensive income (loss), net of tax		370		52		(203)		219
Balance at December 31, 2017, net of tax:	$	(1,638)	$	(5,276)	$	(112)	$	(7,026)

Reclassifications Out of Accumulated Other Comprehensive Income

Reclassifications out of Accumulated Other Comprehensive Income Attributable to 3M

	Amounts Reclassified from
Details about Accumulated Other	Accumulated Other Comprehensive Income
Comprehensive Income Components	Year ended December 31,						Location on Income
(Millions)	2017		2016		2015		Statement
Gains (losses) associated with defined benefit pension and postretirement plans amortization
Transition asset	$	—	$	1	$	1	See Note 12
Prior service benefit		89		92		79	See Note 12
Net actuarial loss		(570)		(506)		(626)	See Note 12
Curtailments/Settlements		(2)		(8)		9	See Note 12
Total before tax		(483)		(421)		(537)
Tax effect		116		148		176	Provision for income taxes
Net of tax	$	(367)	$	(273)	$	(361)
Cash flow hedging instruments gains (losses)
Foreign currency forward/option contracts	$	8	$	110	$	178	Cost of sales
Commodity price swap contracts		—		—		(2)	Cost of sales
Interest rate swap contracts		(1)		(1)		(2)	Interest expense
Total before tax		7		109		174
Tax effect		(3)		(39)		(63)	Provision for income taxes
Net of tax	$	4	$	70	$	111
Total reclassifications for the period, net of tax	$	(363)	$	(203)	$	(250)