Earnings Per Share Computations (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Numerator
Net income attributable to Bemis Company, Inc. (in dollars)	$ 42.3	$ 54.3	$ 86.3	$ 105.5
Income allocated to participating securities (in dollars)	(0.5)	(0.8)	(1.0)	(1.6)
Net income available to common shareholders (in dollars)	$ 41.8	$ 53.5	$ 85.3	$ 103.9
Denominator
Basic weighted-average common shares outstanding	103.1	105.2	103.1	106.1
Dilutive shares	0.7	0.4	0.7	0.4
Weighted-average common and common equivalent shares outstanding - diluted	103.8	105.6	103.8	106.5
Per common share income
Basic (in dollars per share)	$ 0.41	$ 0.51	$ 0.83	$ 0.98
Diluted (in dollars per share)	$ 0.40	$ 0.51	$ 0.82	$ 0.98
Basic weighted-average common shares outstanding	103.1	105.2	103.1	106.1
Basic weighted-average common shares, outstanding and participating securities	104.3	106.7	104.3	107.7
Percentage allocated to common shareholders	98.80%	98.50%	98.80%	98.50%
Antidilutive stock options and stock awards			0.1