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Payments for Convertible Note Hedge, Net, Financing Activities

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

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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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.

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Amount, after accumulated amortization, of debt discount.

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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.

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Debt - Additional Information (Detail) $ / shares in Units, shares in Millions			6 Months Ended
	Dec. 12, 2016 USD ($) d $ / shares	Apr. 27, 2015 USD ($)	Jul. 01, 2018 USD ($) $ / shares shares	Dec. 31, 2017 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
Aggregate principal amount	$ 460,000,000		$ 460,000,000	$ 460,000,000
Debt instrument, interest rate, stated percentage	1.25%
Senior notes maturity date	Dec. 15, 2023
Debt instrument, frequency of periodic payment	Payable semi-annually in arrears on June 15 and December 15 of each year
Debt instrument, date of first required payment	Jun. 15, 2017
Debt instrument, conversion option expiration date	Sep. 15, 2023
Debt instrument conversion rate, shares	0.314463
Debt instrument conversion price \| $ / shares	$ 31.80		$ 31.80
Shares that would be issued upon conversion \| shares			14.5
Strike price per share of warrant \| $ / shares			$ 39.91
Payment for net cost of convertible note hedges net of warrant proceeds			$ 33,000,000
Debt instrument, effective annual interest rate			5.00%
Financing cost	$ 7,200,000		$ 5,800,000
Debt issuance costs, amortization period			7 years
Unamortized discount			$ 87,100,000
Debt Instrument, convertible, remaining discount amortization period			5 years 6 months
Debt instrument, convertible, carrying amount of equity component			$ 100,800,000
Value of notes converted			550,700,000
1.25% Convertible Senior Unsecured Notes Due December 15, 2023 \| Conversion option one
Debt Instrument
Trading days measurement period \| d	20
Consecutive trading days measurement period \| d	30
Percentage of conversion price	130.00%
1.25% Convertible Senior Unsecured Notes Due December 15, 2023 \| 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