Segment and Geographic Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Jan. 27, 2012	Jan. 28, 2011	Jan. 27, 2012	Jan. 28, 2011	Apr. 29, 2011
Segment Reporting Information [Line Items]
Net Sales	$ 3,918	$ 3,857	$ 11,887	$ 11,341
Earnings before income taxes by reportable segment
Reportable segments' earnings before income taxes	1,175	1,169	3,497	3,569
Certain litigation charges, net	0	(13)	0	(292)
Acquisition-related items	(15)	39	1	0
Interest expense, net	(33)	(70)	(103)	(210)
Corporate	(74)	(128)	(281)	(301)
Earnings from continuing operations before income taxes	1,053	997	3,114	2,766
Net assets by reportable segment
Net assets of reportable segments	18,407		18,407		17,231
Short-term borrowings	(1,972)		(1,972)		(1,723)
Long-term debt	(8,248)		(8,248)		(8,112)
Corporate	8,821		8,821		8,402
Total net assets from continuing operations	17,008		17,008		15,798
Net assets and liabilities held for sale	161		161		170
Revenues from External Customers [Line Items]
Net sales to external customers	3,918	3,857	11,887	11,341
United States
Revenues from External Customers [Line Items]
Net sales to external customers	2,145	2,203	6,530	6,610
Europe and Central Asia
Revenues from External Customers [Line Items]
Net sales to external customers	1,046	994	3,135	2,822
Asia Pacific
Revenues from External Customers [Line Items]
Net sales to external customers	574	524	1,760	1,517
Other Foreign
Revenues from External Customers [Line Items]
Net sales to external customers	153	136	462	392
Cardiac and Vascular Group
Segment Reporting Information [Line Items]
Net Sales	2,029	1,995	6,230	5,925
Earnings before income taxes by reportable segment
Reportable segments' earnings before income taxes	657	669	2,008	2,081
Net assets by reportable segment
Net assets of reportable segments	7,073		7,073		6,681
Restorative Therapies Group
Segment Reporting Information [Line Items]
Net Sales	1,889	1,862	5,657	5,416
Earnings before income taxes by reportable segment
Reportable segments' earnings before income taxes	518	500	1,489	1,488
Net assets by reportable segment
Net assets of reportable segments	$ 11,334		$ 11,334		$ 10,550

Total assets pertaining to company's corporate operations.

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Amount related to material litigation reserves and gains recognized in the period in the statement of earnings. Excludes the amount of expense provided in the period for legal fees.

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Corporate overhead expenses

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Net amount of interest expense or income. Interest expense includes the expense associated with the interest paid on outstanding borrowings, including short- and long-term instruments, and the amortization of debt issuance costs and debt discounts. Interest income includes interest earned on cash and cash equivalents, short- and long-term investments, the net realized gains or losses on the sale of available-for-sale securities, and the net realized and unrealized gains or losses on trading securities.

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The amount of net assets (total assets less total liabilities).

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The net of assets or liabilities of a disposal group, including a component of the entity (discontinued operation), to be sold or that has been disposed of through sale, as of the financial statement date.

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The following items are included within acquisition-related items: For business combinations prior to FY09, the amount of the purchase price that is allocated to in-process research and development (IPR&D) was expensed in the period acquired. Similarly, for transactions other than a business combination, such as asset acquisitions, IPR&D is expensed in the period acquired. Additionally, the change in the fair value of the contingent milestone consideration for the reporting period and certain-related acquisition costs, such as banker fees, legal fees, severance, and other professional fees.

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Amount of total revenue from external customers for the reportable segments.

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Amount of income (loss) before income taxes for the reportable segments.

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year or the normal operating cycle, if longer plus capital lease obligations due to be paid more than one year after the balance sheet date.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Amount of net assets (total assets less total liabilities) attributed to the reportable segment.

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