Convertible Notes, Net - Summary of Outstanding Convertible Senior Notes (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2018 USD ($)
5.25% Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Convertible Note Issuance	2013-11
Face Value	$ 172,328
Coupon Rate	5.25%
All-in Cost	5.87%
Conversion Rate	36.5472
Maturity	Dec. 01, 2018
4.38% Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Convertible Note Issuance	2017-05
Face Value	$ 402,500
Coupon Rate	4.38%
All-in Cost	4.85%
Conversion Rate	28.0324
Maturity	May 05, 2022
4.75% Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Convertible Note Issuance	2018-03
Face Value	$ 220,000
Coupon Rate	4.75%
All-in Cost	5.33%
Conversion Rate	27.6052
Maturity	Mar. 15, 2023

Debt Instrument Interest Rate Stated Percentage Including Amortization Cost

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- Definition

Expiration, mandatory redemption, or due date, in CCYY-MM-DD format, of the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction.

+ References

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The month and year (YYYY-MM) the financial instrument was issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

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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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- 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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- 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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