Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	May. 31, 2015	May. 25, 2014
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 4.6	$ 4.0
Common stock, par value (in dollars per share)	$ 5	$ 5
Common stock, authorized (in shares)	1,200,000,000	1,200,000,000
Common stock, issued (in shares)	567,907,172	567,907,172
Treasury stock, common shares (in shares)	139,702,605	145,992,121