Financing Arrangements - Amounts Due under Other Long-Term Financing Arrangements (Detail) (USD $) In Millions, unless otherwise specified	Apr. 24, 2015	Apr. 25, 2014
Debt Disclosure [Abstract]
Other long-term financing arrangements	$ 15.9us-gaap_OtherLongTermDebt	$ 13.1us-gaap_OtherLongTermDebt
Less: current portion	(9.5)us-gaap_OtherLongTermDebtCurrent	(6.6)us-gaap_OtherLongTermDebtCurrent
Non-current portion of other long-term financing arrangements	$ 6.4us-gaap_OtherLongTermDebtNoncurrent	$ 6.5us-gaap_OtherLongTermDebtNoncurrent

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Including both current and noncurrent portions, carrying amount as of the balance sheet date of other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

+ Details

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Period Type:	instant

- Definition

Carrying value as of the balance sheet date of the portion of long-term debt not otherwise specified in the taxonomy that is scheduled to be repaid within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Carrying value as of the balance sheet date of debt not otherwise defined (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

+ Details

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Period Type:	instant