Noncontrolling Interests (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Noncontrolling interests
Purchase of remaining shares owned by the noncontrolling interest of subsidiary									$ 0	$ 89.7	$ 15.9
Net income attributable to Bemis Company, Inc.	40.1	47.4	42.3	44.0	22.8	55.9	54.2	51.2	173.8	184.1	205.1
Decrease in Bemis Company Inc.'s capital in excess of par value due to purchase of noncontrolling interest									0	(48.4)
Change from net income attributable to Bemis Company, Inc. and transfers to noncontrolling interests									173.8	135.7
American Plast S.A.
Noncontrolling interests
Purchase of remaining shares owned by the noncontrolling interest of subsidiary								14.0
Decrease in Bemis Company Inc.'s capital in excess of par value due to purchase of noncontrolling interest									0	(0.2)
Dixie Toga [Member]
Noncontrolling interests
Purchase of remaining shares owned by the noncontrolling interest of subsidiary						90.0
Decrease in Bemis Company Inc.'s capital in excess of par value due to purchase of noncontrolling interest									$ 0	$ (48.2)