Debt (Narrative) (Details) - USD ($)	6 Months Ended
Sep. 28, 2018	Mar. 30, 2018
Debt Instrument [Line Items]
Stock closing price (in dollars per share)	$ 21.28
Convertible Debt \| 2.0% Convertible Senior Notes due August 15, 2021
Debt Instrument [Line Items]
Stated interest rate (as a percent)	2.00%
Convertible Debt \| 2.5% Convertible Senior Notes Due April 1, 2021
Debt Instrument [Line Items]
Stated interest rate (as a percent)	2.50%
If-converted value in excess of principal	$ 134,000,000
Convertible Debt \| 2.0% Convertible Senior Notes Due August 15, 2021
Debt Instrument [Line Items]
Stated interest rate (as a percent)	2.00%
If-converted value in excess of principal	$ 53,000,000
Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity, revolving line of credit	1,000,000,000
Amount outstanding, revolving line of credit	$ 0	$ 0

The amount by which the convertible debt's if-converted value exceeds its principle amount at the balance sheet date, regardless of whether the instrument is currently convertible. This element applies to public companies only.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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- Definition

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

+ 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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

Fair value of the amount outstanding under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13476-108611

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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