Fair Value Measurements (Details) - USD ($) $ in Thousands	Jan. 23, 2016	Apr. 25, 2015
Assets
Transfers from Level 1 to Level 2	$ 0	$ 0
Transfers from Level 2 to Level 1	0	0
Level 1 \| Recurring basis
Assets
Available-for-sale securities	1,231	1,552
Total		1,552
Level 2 \| Recurring basis
Assets
Available-for-sale securities	$ 42,983	58,516
Trading securities		1,127
Total		$ 59,643

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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-Name Accounting Standards Codification
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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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