Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Goodwill
Balance at the beginning of the period	$ 2,254.5	$ 2,399.7
Business disposition		(1.2)
Business acquisition	35.5
Effects of currency exchange rates	(113.5)	(144.0)
Balance at the end of the period	$ 2,176.5	2,254.5
Percentage of fair value exceeding carrying value	25.00%
Contingent impairment of goodwill	$ 78.3
Metal beverage packaging, Americas and Asia
Goodwill
Balance at the beginning of the period	739.5	740.7
Business disposition		(1.2)
Balance at the end of the period	739.5	739.5
Metal beverage packaging, Europe
Goodwill
Balance at the beginning of the period	913.9	1,037.2
Effects of currency exchange rates	(97.3)	(123.3)
Balance at the end of the period	816.6	913.9
Metal food & household products packaging
Goodwill
Balance at the beginning of the period	592.5	613.2
Business acquisition	35.5
Effects of currency exchange rates	(16.2)	(20.7)
Balance at the end of the period	611.8	592.5
Aerospace & technologies
Goodwill
Balance at the beginning of the period	8.6	8.6
Balance at the end of the period	$ 8.6	$ 8.6