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v3.24.3

Notes Payable, Net - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions | 1 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Nov. 30, 2023 | Feb. 28, 2022 | Aug. 31, 2024 | Feb. 01, 2024 | Aug. 31, 2023 | Aug. 31, 2022
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument amount outstanding |  |  | $ 1,420,900,000 |  | $ 1,329,900,000 |
2026 Term Loan |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument, maturity month and year |  |  | 2026-08 |  |  |
Periodic Principal Payment |  |  | $ 3,700,000 |  |  |
Balloon payment |  |  | $ 222,600,000 |  |  |
Swap agreement interest rate |  |  | 75.00% |  |  |
Debt instrument amount outstanding |  |  | $ 251,700,000 |  |  |
2026 Term Loan | SOFR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument, percentage points added to the reference rate |  |  | 1.50% |  |  |
2026 Term Loan | SOFR Adjustment |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument, percentage points added to the reference rate |  |  | 0.10% |  |  |
2027 Term Loan |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument, maturity month and year |  |  | 2027-08 |  |  |
Periodic Principal Payment |  |  | $ 3,100,000 |  |  |
Balloon payment |  |  | $ 283,700,000 |  |  |
Swap agreement interest rate |  |  | 100.00% |  |  |
Debt instrument amount outstanding |  |  | $ 320,500,000 |  |  |
2027 Term Loan | SOFR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument, percentage points added to the reference rate |  |  | 1.625% |  |  |
2027 Term Loan | SOFR Adjustment |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument, percentage points added to the reference rate |  |  | 0.10% |  |  |
2.875% Convertible senior notes, due 2028 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument, effective interest rate |  |  | 5.75% |  |  |
Debt instrument, interest rate |  |  | 2.875% |  | 2.875% | 2.875%
Description of long term debt |  |  | Convertible senior notes, due 2028 (2028 Convertible Notes), bear interest at a fixed rate of 2.875%, paid semiannually in arrears on April 15th and October 15th. |  |  |
Frequency of payments |  |  | semiannually |  |  |
Debt instrument, maturity date |  |  | Apr. 15, 2028 |  |  |
Convertible senior notes |  |  | $ 373,800,000 |  | $ 373,800,000 |
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 |  |  |
Number of shares reserved for future issuance |  |  | 8.2 |  |  |
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 2024 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument, interest rate |  |  | 2.875% |  | 2.875% | 2.875%
Debt instrument, maturity date |  |  | Feb. 01, 2024 |  |  |
Convertible senior notes |  |  | $ 0 | $ 47,700,000 | $ 47,700,000 |
Leasing Nonrecourse Term Loans | Asset-Backed Term Notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument amount outstanding |  |  | $ 471,600,000 |  |  |
GBX Leasing Warehouse Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Swap agreement interest rate |  |  | 74.00% |  |  |
GBX Leasing Warehouse Facility | SOFR Adjustment |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument, percentage points added to the reference rate |  |  | 0.11% |  |  |
GBX Leasing Warehouse Facility | GBXL I Series 2022-1 Notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt, Principal amount |  | $ 323,300,000 |  |  |  |
Debt instrument, maturity month and year |  | 2022-02 |  |  |  |
Frequency of payments |  |  | monthly |  |  |
Debt instrument, maturity date |  |  | Feb. 20, 2052 |  |  |
Debt instrument, repayment date |  |  | Jan. 20, 2029 |  |  |
Debt instrument, maturity year |  |  | 2052 |  |  |
Debt instruments additional interest rate per annum |  |  | 4.00% |  |  |
GBX Leasing Warehouse Facility | GBXL I Series 2022-1 Notes | GBXL I Series 2022-1 Class A Secured Railcar Equipment Notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt, Principal amount |  |  | $ 274,800,000 |  |  |
Debt instrument, interest rate |  |  | 2.87% |  |  |
GBX Leasing Warehouse Facility | GBXL I Series 2022-1 Notes | GBXL I Series 2022-1 Class B Secured Railcar Equipment Notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt, Principal amount |  |  | $ 20,700,000 |  |  |
Debt instrument, interest rate |  |  | 3.45% |  |  |
GBX Leasing Warehouse Facility | 2023 GBXL Notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt, Principal amount | $ 178,500,000 |  |  |  |  |
Debt instrument, maturity month and year | 2023-11 |  |  |  |  |
Frequency of payments |  |  | monthly |  |  |
Debt instrument, maturity date |  |  | Nov. 20, 2053 |  |  |
Debt instrument, repayment date |  |  | Nov. 20, 2030 |  |  |
Debt instrument, maturity year |  |  | 2053 |  |  |
Debt instruments additional interest rate per annum |  |  | 4.00% |  |  |
GBX Leasing Warehouse Facility | 2023 GBXL Notes | GBXL I Series 2023-1 Class A Secured Railcar Equipment Notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt, Principal amount |  |  | $ 156,700,000 |  |  |
Debt instrument, interest rate |  |  | 6.42% |  |  |
GBX Leasing Warehouse Facility | 2023 GBXL Notes | GBXL I Series 2023-1 Class B Secured Railcar Equipment Notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt, Principal amount |  |  | $ 19,400,000 |  |  |
Debt instrument, interest rate |  |  | 7.28% |  |  |

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