Debt - Convertible Senior Notes (Details) $ / shares in Units, $ in Thousands, shares in Millions	Mar. 06, 2017 USD ($) item $ / shares shares	Dec. 30, 2017 USD ($)
Amended Credit Agreement
Debt
Repayment of debt	$ 72,500
1.375% Convertible Senior Notes
Debt
Principal amount of convertible senior notes sold in private placement	$ 400,000	$ 400,000
Stated interest rate	1.375%
Conversion rate	10.7744
Principal amount of notes	$ 1,000,000
Number of shares of common stock \| shares	4.3
Initial conversion price \| $ / shares	$ 92.81
Number of trading days within 30 trading day period \| item	20
Number of consecutive trading days \| item	30
Minimum amount the sales price of the Company's stock exceeds the conversion price (as a percent)	130.00%
Number of consecutive business days after the 10 consecutive trading day period	5 days
Number of consecutive trading days before the five consecutive business days	10 days
Maximum amount the sales price of the Company's stock exceeds the conversion price (as a percent)	98.00%

Amount of principal considered for converting convertible debt into equity securities.

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- Definition

The number of equity shares issued by the holder of the debt instrument would receive if the debt was converted to equity.

+ References

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- Definition

Threshold number of specified consecutive business days that common stock price per $1,000 of convertible debt instruments must not exceed the threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

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Threshold number of specified consecutive trading days that common stock price per $1,000 of convertible debt instruments must not exceed the threshold percentage, and which occurs before the specified consecutive business period to trigger conversion feature.

+ References

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Maximum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

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No definition available.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

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

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21506-112644

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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

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Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

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Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

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

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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.

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The cash outflow for the settlement of obligation drawn from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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