Restructuring Charges (Details) - USD ($)	12 Months Ended
Apr. 26, 2019	Apr. 27, 2018	Apr. 28, 2017
Changes in Restructuring Reserves
Accrual adjustments	$ (17,000,000)	$ (34,000,000)
Enterprise Excellence
Changes in Restructuring Reserves
Beginning balance	29,000,000	0
Charges	424,000,000	96,000,000
Cash payments	(314,000,000)	(67,000,000)
Settled non-cash	(17,000,000)
Ending balance	122,000,000	29,000,000	$ 0
Enterprise Excellence \| Employee Termination Benefits
Changes in Restructuring Reserves
Beginning balance	27,000,000	0
Charges	192,000,000	35,000,000
Cash payments	(118,000,000)	(8,000,000)
Settled non-cash	0
Ending balance	101,000,000	27,000,000	0
Enterprise Excellence \| Associated Costs
Changes in Restructuring Reserves
Beginning balance	2,000,000	0
Charges	193,000,000	61,000,000
Cash payments	(186,000,000)	(59,000,000)
Settled non-cash	0
Ending balance	9,000,000	2,000,000	0
Enterprise Excellence \| Asset Write-downs
Changes in Restructuring Reserves
Beginning balance	0	0
Charges	17,000,000	0
Cash payments	0	0
Settled non-cash	(17,000,000)
Ending balance	0	0	0
Enterprise Excellence \| Other Costs
Changes in Restructuring Reserves
Beginning balance	0	0
Charges	22,000,000	0
Cash payments	(10,000,000)	0
Settled non-cash	0
Ending balance	12,000,000	0	0
Cost Synergies
Changes in Restructuring Reserves
Beginning balance	138,000,000	291,000,000	250,000,000
Charges	0	45,000,000	368,000,000
Cash payments	(57,000,000)	(164,000,000)	(232,000,000)
Settled non-cash			(27,000,000)
Accrual adjustments	(17,000,000)	(34,000,000)	(68,000,000)
Ending balance	64,000,000	138,000,000	291,000,000
Cost Synergies \| Employee Termination Benefits
Changes in Restructuring Reserves
Beginning balance	116,000,000	261,000,000	213,000,000
Charges		25,000,000	287,000,000
Cash payments	(44,000,000)	(132,000,000)	(179,000,000)
Settled non-cash			0
Accrual adjustments	(13,000,000)	(38,000,000)	(60,000,000)
Ending balance	59,000,000	116,000,000	261,000,000
Cost Synergies \| Asset Write-downs
Changes in Restructuring Reserves
Beginning balance	0	0	0
Charges		0	27,000,000
Cash payments	0	0	0
Settled non-cash			(27,000,000)
Accrual adjustments	0	0	0
Ending balance	0	0	0
Cost Synergies \| Other Costs
Changes in Restructuring Reserves
Beginning balance	22,000,000	30,000,000	37,000,000
Charges		20,000,000	54,000,000
Cash payments	(13,000,000)	(32,000,000)	(53,000,000)
Settled non-cash			0
Accrual adjustments	(4,000,000)	4,000,000	(8,000,000)
Ending balance	$ 5,000,000	$ 22,000,000	$ 30,000,000

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

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