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v3.21.2

Notes Payable, Net - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Apr. 30, 2021 | Aug. 31, 2021 | Aug. 31, 2020 | Aug. 31, 2019
Debt Instrument [Line Items] |  |  |  |
Debt instrument amount outstanding |  | $ 915,525,000 | $ 833,993,000 |
Debt issuance costs |  | 8,597,000 | $ 3,623,000 |
Loss on extinguishment of debt |  | 5,800,000 |  |
Other Term Loan Due September 2022 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Senior term debt |  | 400,000 |  |
Other Term Loan Due January 2022 to April 2026 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Unsecured debt |  | 1,700,000 |  |
2026 Term Loan |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Senior term debt |  | $ 291,900,000 |  |
Debt instrument, maturity month and year |  | 2026-08 |  |
Periodic Principal Payment |  | $ 3,650,000 |  |
Balloon payment |  | $ 222,600,000 |  |
Swap agreement interest rate |  | 50.00% |  |
Fixed interest rate |  | 3.19% |  |
Debt instrument amount outstanding |  | $ 291,900,000 |  |
2026 Term Loan | LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt instrument, percentage points added to the reference rate |  | 1.50% |  |
2027 Term Loan |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Senior term debt |  | $ 200,000,000.0 |  |
Debt instrument, maturity month and year |  | 2027-08 |  |
Periodic Principal Payment |  | $ 1,750,000 |  |
Balloon payment |  | $ 158,000,000.0 |  |
Swap agreement interest rate |  | 50.00% |  |
Fixed interest rate |  | 4.62% |  |
Debt instrument amount outstanding |  | $ 200,000,000.0 |  |
2027 Term Loan | LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt instrument, percentage points added to the reference rate |  | 1.625% |  |
2.875% Convertible senior notes, due 2028 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Proceeds from convertible senior notes | $ 373,800,000 |  |  |
Debt instrument, interest rate | 2.875% | 2.875% |  |
Description of long term debt |  | These interest payments are payable semiannually in arrears on April 15 and October 15, 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 |  | $ 55.46 |  |
Initial debt discount |  | $ 73,600,000 |  |
Debt issuance costs |  | $ 12,000,000.0 |  |
Number of shares reserved for future issuance |  | 8.8 |  |
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% Convertible senior notes, due 2028 | ASC 470-20 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Proceeds from convertible senior notes |  | $ 373,800,000 |  |
Convertible notes, fair value |  | 300,200,000 |  |
Convertible notes, equity component |  | 73,600,000 |  |
2.875% Convertible senior notes, due 2028 | ASC 470-20 | Additional Paid-in Capital |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Convertible Senior Notes, equity component, net of tax |  | $ 17,300,000 |  |
2.875% Convertible senior notes, due 2028 | ASC 470-20 | Measurement Input, Risk Free Interest Rate |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Fair value assumed, interest rate |  | 0.0575 |  |
2.875% Convertible senior notes, due 2024 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt instrument, interest rate |  | 2.875% | 2.875% | 2.875%
Description of long term debt |  | Convertible senior notes, due 2024, bear interest at a fixed rate of 2.875%, paid semi-annually in arrears on February 1st and August 1st. |  |
Frequency of payments |  | semi-annually |  |
Debt instrument, maturity date |  | Feb. 01, 2024 |  |
Convertible notes initial conversion rate, shares per $1,000 principal amount |  | 0.166234 |  |
Debt instrument, convertible, principal amount |  | $ 1,000 |  |
Convertible notes conversion rate, per share |  | $ 60.16 |  |
Initial debt discount |  | $ 33,100,000 |  |
Debt issuance costs |  | $ 8,000,000.0 |  |
Number of shares reserved for future issuance |  | 1.0 |  |
Convertible debt retired |  | $ 227,300,000 |  |
2.875% Convertible senior notes, due 2024 | ASC 470-20 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Proceeds from convertible senior notes |  | 275,000,000 |  |
Convertible notes, fair value |  | 241,900,000 |  |
Convertible notes, equity component |  | $ 2,600,000 | $ 33,100,000 |
2.875% Convertible senior notes, due 2024 | ASC 470-20 | Measurement Input, Risk Free Interest Rate |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Fair value assumed, interest rate |  | 0.05 |  |
2.25% Convertible senior notes, due 2024 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt instrument, interest rate |  | 2.25% | 2.25% | 2.25%

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