Business Segments and Related Information (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
	May 27, 2012	May 29, 2011
Allocation of net derivative gains (losses) from economic hedges of forecasted commodity consumption and the foreign currency risk
Net derivative gains (losses) incurred	$ (66.8)	$ 35.1
Net derivative gains allocated to Reporting Segments	24.4	0.6
Net derivative gains (losses) recognized in general corporate expenses	(91.2)	34.5
Consumer foods [Member]
Allocation of net derivative gains (losses) from economic hedges of forecasted commodity consumption and the foreign currency risk
Net derivative gains allocated to Reporting Segments	24.9	3.6
Commercial foods [Member]
Allocation of net derivative gains (losses) from economic hedges of forecasted commodity consumption and the foreign currency risk
Net derivative losses allocated to Reporting Segments	$ (0.5)	$ (3.0)