Acquisitions and Acquisition-Related Items , Contingent Consideration (Details) - USD ($) $ in Millions	12 Months Ended
Apr. 28, 2017	Apr. 29, 2016
Fair Value Inputs
Contingent consideration	$ 377	$ 264
Reconciliation of Beginning and Ending Balances of Contingent Milestone Payments Associated with Acquisitions
Beginning Balance	377	264
Purchase price contingent consideration	28	149
Contingent consideration payments	(76)	(22)
Change in fair value of contingent consideration	(83)	(14)
Ending Balance	246	$ 377
Fair Value, Measurements, Recurring \| Level 3 \| Revenue-based payments
Fair Value Inputs
Contingent consideration	106
Reconciliation of Beginning and Ending Balances of Contingent Milestone Payments Associated with Acquisitions
Ending Balance	$ 106
Fair Value, Measurements, Recurring \| Level 3 \| Revenue-based payments \| Discounted cash flow \| Minimum
Fair Value Inputs
Discount rate	11.00%
Probability of payment	30.00%
Fair Value, Measurements, Recurring \| Level 3 \| Revenue-based payments \| Discounted cash flow \| Maximum
Fair Value Inputs
Discount rate	32.50%
Probability of payment	100.00%
Fair Value, Measurements, Recurring \| Level 3 \| Product development-based payments
Fair Value Inputs
Contingent consideration	$ 140
Reconciliation of Beginning and Ending Balances of Contingent Milestone Payments Associated with Acquisitions
Ending Balance	$ 140
Fair Value, Measurements, Recurring \| Level 3 \| Product development-based payments \| Discounted cash flow \| Minimum
Fair Value Inputs
Discount rate	0.30%
Probability of payment	75.00%
Fair Value, Measurements, Recurring \| Level 3 \| Product development-based payments \| Discounted cash flow \| Maximum
Fair Value Inputs
Discount rate	5.50%
Probability of payment	100.00%

-- None. No documentation exists for this element. --

No definition available.

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- Definition

Contingent milestone payments in business acquisition transactions.

+ References

No definition available.

+ Details

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- Definition

Amount of contingent consideration arrangement resulting from business combinations.

+ References

No definition available.

+ Details

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- Definition

Percentage of likelihood a loan will be repaid, used as an input to measure fair value.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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-Publisher FASB
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- References

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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