Debt - Schedule of Convertible Debt (Details) (USD $) In Thousands, unless otherwise specified	May 03, 2015	Apr. 27, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Convertible debt, net of current portion	221,406us-gaap_ConvertibleDebtNoncurrent	$ 212,253us-gaap_ConvertibleDebtNoncurrent
Current portion of convertible debt	0us-gaap_ConvertibleDebtCurrent	40,015us-gaap_ConvertibleDebtCurrent
Convertible Debt	221,406us-gaap_ConvertibleDebt	252,268us-gaap_ConvertibleDebt
0.5% Convertible Senior Notes Due 2033
Debt Instrument [Line Items]
Convertible debt, net of current portion		212,253
Interest rate	0.50%	0.50%	0.50%
5.0% Convertible Senior Notes Due 2029
Debt Instrument [Line Items]
Current portion of convertible debt		$ 40,015
Interest rate	5.00%	5.00%

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16(a)(2))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: 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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Balance Type:	credit
Period Type:	instant

- Definition

The portion of the carrying value of long-term convertible debt as of the balance sheet date that is scheduled to be repaid within one year or in the normal operating cycle if longer. Convertible debt is a financial instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

+ 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 210.5-02.20)

-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

-Article 5

+ Details

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- Definition

Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

+ References

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Details

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