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v3.21.2

Notes Payable, Net - Additional Information (Detail) | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | ---
Apr. 30, 2021 USD ($) | May 31, 2021 USD ($) $ / shares | May 31, 2021 USD ($) $ / shares | Aug. 31, 2020 USD ($) | May 31, 2020
Debt Instrument [Line Items] |  |  |  |  |
Loss on extinguishment of debt | $ 4,800,000 | $ 4,763,000 | $ 4,763,000 |  |
2.875% Convertible senior notes, due 2028 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Proceeds from convertible senior notes | 373,800,000 |  | $ 373,800,000 |  |
Debt instrument, interest rate |  | 2.875% | 2.875% |  |
Principal amount outstanding |  | $ 373,750,000 | $ 373,750,000 |  |
Description of long term debt |  |  | The notes bear interest at an annual rate of 2.875% payable semiannually in arrears on April 15 and October 15 of each year, commencing October 15, 2021. |  |
Frequency of payments |  |  | semiannually |  |
Debt instrument, maturity date |  |  | Apr. 15, 2028 |  |
Convertible notes initial conversion rate, shares per $1,000 principal amount |  |  | 0.180317 |  |
Debt instrument, convertible, principal amount |  |  | $ 1,000 |  |
Convertible notes conversion rate, per share | $ / shares |  | $ 55.46 | $ 55.46 |  |
Convertible senior notes, due 2028 - equity component, net of tax |  |  | $ 73,600,000 |  |
Debt instrument amortized to interest expense, effective interest rate |  |  | 5.75% |  |
Convertible notes, liability and equity component |  |  | $ 12,000,000.0 |  |
2.875% Convertible senior notes, due 2028 | Redemption on or After April 15, 2025 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument, convertible, latest date |  |  | Jan. 15, 2028 |  |
Debt instrument redemption start date |  |  | Apr. 15, 2025 |  |
Debt instrument redemption end date |  |  | Apr. 15, 2028 |  |
Debt instrument, convertible, threshold percentage of stock price trigger |  |  | 130.00% |  |
Debt instrument redemption description |  |  | Additionally, the Company may elect to call the notes on or after April 15, 2025 and on or before the 40th trading day prior to April 15, 2028, at a cash redemption price described in the 2028 Notes Indenture if the stock price exceeds 130% of the conversion price during certain trading days as defined in the 2028 Notes Indenture. |  |
2.875% and 2.25% Convertible senior notes, due 2024 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Net proceeds used to repurchase convertible notes | 283,300,000 |  |  |  |
Principal amount of debt repurchased | $ 207,100,000 |  |  |  |
2.875% Convertible senior notes, due 2024 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument, interest rate | 2.875% | 2.875% | 2.875% |  | 2.875%
Fair value of the liability component | $ 198,100,000 |  |  |  |
Principal amount outstanding | $ 67,900,000 | $ 67,876,000 | $ 67,876,000 | $ 275,000,000 |
2.25% Convertible senior notes, due 2024 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument, interest rate | 2.25% | 2.25% | 2.25% |  | 2.25%
Fair value of the liability component | $ 46,500,000 |  |  |  |
Principal amount outstanding |  |  |  | $ 50,000,000 |

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