Notes Payable, Net (Detail) - USD ($) $ in Thousands	Aug. 31, 2017	Aug. 31, 2016
Debt Instrument [Line Items]
Term loans	$ 184,001	$ 184,906
Other notes payable	19,540
Notes payable, gross	597,604	303,969
Debt discount and issuance costs	(39,376)	(2,116)
Notes payable, net	558,228	301,853
2018 Senior Notes
Debt Instrument [Line Items]
Convertible senior notes	119,063	$ 119,063
2024 Convertible Senior Notes
Debt Instrument [Line Items]
Convertible senior notes	$ 275,000

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.

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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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Carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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