Outstanding Convertible Note Balances (Detail) (Senior Notes, USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Jun. 17, 2014
Senior Notes
Convertible Debt [Line Items]
Principal	$ 200,000	$ 200,000
Less: debt discount, net	45,009
Net carrying amount	154,991
Equity component	$ 40,896

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Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

+ References

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- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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-Publisher FASB

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- Definition

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

+ References

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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