Investments, Other Disclosures (Details) (USD $) In Millions, unless otherwise specified	Jan. 23, 2015	Apr. 25, 2014
Investments [Abstract]
Aggregate carrying amount of investments in equity and other securities that are accounted for using the cost or equity method	$ 458	$ 666

This item represents equity method investments in common stock and investments accounted for under the cost-method at cost without quoted market price.

No definition available.

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