Investments (Other Disclosures) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Jul. 29, 2011	Oct. 28, 2011	Apr. 29, 2011
Investments [Abstract]
Non-cash gain on previously held minority investments	$ 38
Aggregate carrying amount of equity and other securities without a quoted market price and accounted for using the cost or equity method		831	656
Investments with trading restrictions		$ 464

This item represents equity method investments in common stock and investments accounted for under the cost-method at cost with quoted market price.

No definition available.

Name:	mdt_CostAndEquityMethodInvestmentWithoutQuotedMarketPrice
Namespace Prefix:	mdt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant