Pre-Tax Income and Income Taxes (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
May 27, 2012	May 29, 2011	May 30, 2010
Income tax reconciliation
Computed U.S. Federal income taxes	$ 232.2	$ 438.3	$ 322.9
State income taxes, net of U.S. Federal tax impact	12.0	20.0	15.7
Tax credits and domestic manufacturing deduction	(20.5)	(27.5)	(27.3)
Foreign tax credits and related items, net	(0.6)	(0.2)	(4.3)
IRS audit adjustments and settlements	0.8	0.5	(17.4)
Non-taxable gain from investment in ATFL	(20.5)
Change in valuation allowance	(7.1)	2.1	(4.6)
Other	(0.5)	(11.6)	7.3
Income tax expense (benefit) continuing operations, total	$ 195.8	$ 421.6	$ 292.3

Income tax reconciliation tax credits and domestic manufacturing deduction.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to pretax Income or Loss from continuing operations; income tax expense or benefit may include interest and penalties on tax uncertainties based on the entity's accounting policy.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to changes in the valuation allowance for deferred tax assets in the period.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to foreign tax credits generated or utilized under enacted tax laws during the period.

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