Fair Value Measurements - Fair Value of Assets and Liabilities Measured on Recurring Basis (Detail) (USD $) In Millions, unless otherwise specified	Nov. 25, 2012	May 27, 2012
Assets:
Derivative assets	$ 72.2	$ 58.7
Available-for-sale securities	1.6	1.6
Deferred compensation assets	5.8	5.8
Total assets	79.6	66.1
Liabilities:
Derivative liabilities	192.7	215.4
Deferred compensation liabilities	31.9	27.1
Total liabilities	224.6	242.5
Level 1 [Member]
Assets:
Derivative assets	17.6	13.8
Available-for-sale securities	1.6	1.6
Deferred compensation assets	5.8	5.8
Total assets	25.0	21.2
Liabilities:
Deferred compensation liabilities	31.9	27.1
Total liabilities	31.9	27.1
Level 2 [Member]
Assets:
Derivative assets	54.6	44.9
Total assets	54.6	44.9
Liabilities:
Derivative liabilities	192.7	215.4
Total liabilities	192.7	215.4
Level 3 [Member]
Assets:
Derivative assets
Available-for-sale securities
Deferred compensation assets
Total assets
Liabilities:
Derivative liabilities
Deferred compensation liabilities
Total liabilities