Retirement Benefit Plans, Other Disclosures (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Apr. 27, 2012	Apr. 29, 2011	Apr. 30, 2010
Retirement Benefit Plans Disclosure
Cost of retirement benefit plans	$ 319	$ 368	$ 237
Underfunded status of the plan	(621)	(253)
Non-cash charge due to PPACA and Reconciliation Act			15
Plan funded percentage description	in excess of 80 percent
Expected decline in healthcare cost trend rates of 5 year period	the trend rates are expected to decline to 5.0 percent over a five-year period
Defined Contribution Savings Plan
Expense under defined contribution plans	106	147	110
PIA
Defined Contribution Savings Plan
Expense under defined contribution plans	48	46	41
U.S. Pension Benefits
Retirement Benefit Plans Disclosure
Cost of retirement benefit plans	102	103	39
Underfunded status of the plan	$ (407)	$ (124)

The amount of pension and other (such as medical, dental and life insurance) postretirement benefit costs recognized during the period for (1) defined benefit plans (periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss) on assets, prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments) and for (2) defined contribution plans (to the extent that a plan's defined contributions to an individual's account are to be made for periods in which that individual renders services, the net cost for a period is the contribution called for in that period; if a plan calls for contributions for periods after an individual retires or terminates, the estimated cost is accrued during the employee's service period).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Name Statement of Financial Accounting Standard (FAS)

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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