Consolidated Statement of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Consolidated Statement of Comprehensive Income
Net income including noncontrolling interest	$ 1,141	$ 1,103
Other comprehensive income (loss), net of tax:
Cumulative translation adjustment	134	242
Defined benefit pension and postretirement plans adjustment	97	76
Debt and equity securities, unrealized gain (loss)	3	(1)
Cash flow hedging instruments, unrealized gain (loss)	(15)	(17)
Total other comprehensive income (loss), net of tax	219	300
Comprehensive income (loss) including noncontrolling interest	1,360	1,403
Comprehensive (income) loss attributable to noncontrolling interest	5	(16)
Comprehensive income (loss) attributable to 3M	$ 1,365	$ 1,387