Carrying Value of Convertible Senior Notes (Detail) - 2.125% Convertible Senior Notes due 2021 $ in Thousands	Jun. 30, 2016 USD ($)
Debt Instrument [Line Items]
Principal amount	$ 115,000
Unamortized debt discount	(18,387)
Unamortized debt issuance costs	(3,233)
Total convertible senior notes	$ 93,380

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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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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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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