Stockholders' Equity (Schedule of accumulated other comprehensive loss balances, net of taxes) (Details) (USD $) In Millions, unless otherwise specified	May 26, 2013	May 27, 2012
Accumulated Other Comprehensive Income (Loss), Net of Tax:
Foreign currency translation adjustment	$ 263.1	$ 282.9
Unrealized gain (loss) from:
Securities	2.6	1.8
Hedge derivatives	(41.7)	(75.3)
Pension Other Postretirement And Postemployment Benefits [Abstract]
Net actuarial gain (loss)	(1,801.5)	(1,945.9)
Prior service costs (credits)	(7.8)	(7.2)
Accumulated other comprehensive loss	$ (1,585.3)	$ (1,743.7)