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v3.8.0.1

Debt - Additional Information (Detail) $ / shares in Units, shares in Millions |  | 9 Months Ended |  |
--- | --- | --- | --- | ---
Apr. 27, 2015 USD ($) | Oct. 01, 2017 USD ($) d $ / shares shares | Dec. 31, 2016 USD ($) | Dec. 12, 2016 USD ($)
Debt Instrument |  |  |  |
Term of loan, years | 5 years |  |  |
Pledge percentage of capital stock | 65.00% |  |  |
1.25% Convertible Senior Unsecured Notes Due December 15, 2023 |  |  |  |
Debt Instrument |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  | 1.25%
Aggregate principal amount |  | $ 460,000,000 | $ 460,000,000 | $ 460,000,000
Senior notes maturity date |  | Dec. 15, 2023 |  |
Trading days measurement period | d |  | 20 |  |
Consecutive trading days measurement period | d |  | 30 |  |
Percentage of conversion price |  | 130.00% |  |
Debt instrument conversion ratio |  | 0.314102 |  |
Initial debt conversion price | $ / shares |  | $ 31.84 |  |
Shares that would be issued upon conversion | shares |  | 14.4 |  |
Strike price per share of warrant | $ / shares |  | $ 39.95 |  |
Debt instrument, effective annual interest rate |  | 5.00% |  |
Financing cost |  | $ 6,500,000 |  | $ 7,200,000
Debt issuance costs, amortization period |  | 7 years |  |
Unamortized discount |  | $ 97,400,000 |  |
Debt Instrument, convertible, remaining discount amortization period |  | 6 years 3 months 19 days |  |
Debt instrument, convertible, carrying amount of equity component |  | $ 100,800,000 |  |
Value of notes converted |  | $ 538,700,000 |  |
Conversion option two |  |  |  |
Debt Instrument |  |  |  |
Trading days measurement period | d |  | 5 |  |
Consecutive trading days measurement period | d |  | 5 |  |
Percentage of closing sale price of common stock and conversion rate product |  | 98.00% |  |
Maximum |  |  |  |
Debt Instrument |  |  |  |
Aggregate principal amount | $ 150,000,000 |  |  |
Commitment fee percentage of unused portion of credit facility | 0.35% |  |  |
Minimum |  |  |  |
Debt Instrument |  |  |  |
Commitment fee percentage of unused portion of credit facility | 0.125% |  |  |
Base Rate | Maximum |  |  |  |
Debt Instrument |  |  |  |
Debt instrument, basis spread on variable rate | 1.00% |  |  |
Base Rate | Minimum |  |  |  |
Debt Instrument |  |  |  |
Debt instrument, basis spread on variable rate | 0.00% |  |  |
London Interbank Offered Rate (LIBOR) | Maximum |  |  |  |
Debt Instrument |  |  |  |
Debt instrument, basis spread on variable rate | 2.00% |  |  |
London Interbank Offered Rate (LIBOR) | Minimum |  |  |  |
Debt Instrument |  |  |  |
Debt instrument, basis spread on variable rate | 1.00% |  |  |
Revolving Credit Facility |  |  |  |
Debt Instrument |  |  |  |
Financing cost |  | $ 2,300,000 |  |
Financing cost, amortization term |  | 5 years |  |
Revolving Credit Facility | Maximum |  |  |  |
Debt Instrument |  |  |  |
Credit facility, borrowing capacity | $ 350,000,000 |  |  |

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- Definition Amount of a favorable spread to a debt holder between the amount of debt being converted and the value of the securities received upon conversion. This is an embedded conversion feature of convertible debt issued that is in-the-money at the commitment date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21538-112644 + Details
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- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any 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 + Details
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