Debt - Long-Term Debt (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2016	Apr. 25, 2015
Debt Instrument [Line Items]
Less: Deferred debt issuance costs	$ (3,970)	$ (2,458)
Total	1,038,655	722,542
Less: current debt obligations	(16,500)	0
Long-term debt	$ 1,022,155	$ 722,542
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Interest floating rate	3.875%
Senior Notes 5.75% [Member]
Debt Instrument [Line Items]
Fixed rate	5.75%	5.75%
Fixed rate senior notes due fiscal 2018 to 2025	$ 150,000	$ 150,000
Senior Notes 2.95% [Member]
Debt Instrument [Line Items]
Fixed rate	2.95%	2.95%
Fixed rate senior notes due fiscal 2018 to 2025	$ 60,000	$ 60,000
Senior Notes 3.59% [Member]
Debt Instrument [Line Items]
Fixed rate	3.59%	3.59%
Fixed rate senior notes due fiscal 2018 to 2025	$ 165,000	$ 165,000
Senior Notes 3.74% [Member]
Debt Instrument [Line Items]
Fixed rate	3.74%	3.74%
Fixed rate senior notes due fiscal 2018 to 2025	$ 100,000	$ 100,000
Senior Notes 3.48% [Member]
Debt Instrument [Line Items]
Fixed rate	3.48%	3.48%
Fixed rate senior notes due fiscal 2018 to 2025	$ 250,000	$ 250,000
Senior Notes 1.81% [Member]
Debt Instrument [Line Items]
Fixed rate	1.81%	1.81%
Fixed rate senior notes due fiscal 2018 to 2025	$ 317,625	$ 0

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Section S99
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-Subparagraph (SX 210.7-03(a)(16))
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

No definition available.

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