Summary of Significant Accounting Policies - Dividends (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Apr. 24, 2015	Apr. 25, 2014	Apr. 26, 2013
Accounting Policies [Abstract]
Cash dividends paid to common stock holders	$ 29,056us-gaap_DividendsCommonStockCash	$ 31,694us-gaap_DividendsCommonStockCash
Dividend equivalent rights earned on deferred restricted stock units	370	575
Total dividends	$ 29,426us-gaap_Dividends	$ 32,269us-gaap_Dividends	$ 30,214us-gaap_Dividends

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Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 405

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

+ Details

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- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

+ References

+ Details

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- Definition

Amount of paid and unpaid cash dividends declared and applicable to holders of share-based compensation, for example, but not limited to, non-vested shares, stock options, or restricted stock units.

+ References

No definition available.

+ Details

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