Debt instrument maturity month and year.

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Debt instrument, maturity year.

+ References

No definition available.

+ Details

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- Definition

Debt instrument repayment date.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Debt instruments additional interest rate per annum.

+ References

No definition available.

+ Details

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- Definition

Line of credit, guaranteed amount.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Maturity Month and Year

+ References

No definition available.

+ Details

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- Definition

Line of credit renewal month and year.

+ References

No definition available.

+ Details

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- Definition

Percentage Of Joint Venture Debt Guaranteed

+ References

No definition available.

+ Details

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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- Definition

The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

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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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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- Definition

Latest date when the debt instrument can be converted into equity, in YYYY-MM-DD format.

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- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

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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- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Amount of the required periodic payments applied to principal.

+ References

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Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

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No definition available.

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-Topic 942
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Debt, Net - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended		12 Months Ended
	Nov. 30, 2023	Feb. 28, 2022	Aug. 31, 2025	Aug. 31, 2024	Feb. 01, 2024	Aug. 31, 2023
Debt Instrument [Line Items]
Debt instrument amount outstanding			$ 1,764.5
European
Debt Instrument [Line Items]
Line of credit, guaranteed amount			$ 35.1
European \| Maximum
Debt Instrument [Line Items]
Line of credit maturity date			2026-09
European \| Minimum
Debt Instrument [Line Items]
Line of credit maturity date			2025-10
Mexico
Debt Instrument [Line Items]
Line of credit facility maximum capacity			$ 56.0
Mexico \| Maximum
Debt Instrument [Line Items]
Line of credit maturity date			2027-03
Mexico \| Minimum
Debt Instrument [Line Items]
Line of credit maturity date			2026-06
WIBOR \| European \| Maximum
Debt Instrument [Line Items]
Debt instrument, percentage points added to the reference rate			1.40%
WIBOR \| European \| Minimum
Debt Instrument [Line Items]
Debt instrument, percentage points added to the reference rate			1.10%
EURIBOR \| European
Debt Instrument [Line Items]
Debt instrument, percentage points added to the reference rate			1.90%
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			The 2028 Convertible Notes bear interest at a fixed rate of 2.875%, paid semiannually in arrears on April 15th and October 15th.
Debt instrument, maturity date			Apr. 15, 2028
Convertible notes initial conversion rate, shares per $1,000 principal amount			0.181496
Debt instrument, convertible, principal amount			$ 1,000.0
Convertible notes conversion rate, per share			$ 55.1
Number of shares reserved for future issuance			8.1
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%	2.875%
Corporate Senior Term Debt
Debt Instrument [Line Items]
Debt instrument, maturity month and year			2030-05
Periodic Principal Payment			$ 3.1
Balloon payment			$ 190.6
Swap agreement interest rate			75.00%
Corporate Senior Term Debt \| Minimum
Debt Instrument [Line Items]
Debt instrument, maturity month and year			2026-08
Corporate Senior Term Debt \| SOFR
Debt Instrument [Line Items]
Debt instrument, percentage points added to the reference rate			1.50%
Corporate Senior Term Debt \| SOFR Adjustment
Debt Instrument [Line Items]
Debt instrument, percentage points added to the reference rate			0.10%
Leasing Senior Term Debt
Debt Instrument [Line Items]
Debt instrument, maturity month and year			2027-08
Periodic Principal Payment			$ 3.1
Balloon payment			$ 283.7
Swap agreement interest rate			100.00%
Leasing Senior Term Debt \| SOFR
Debt Instrument [Line Items]
Debt instrument, percentage points added to the reference rate			1.625%
Leasing Senior Term Debt \| SOFR Adjustment
Debt Instrument [Line Items]
Debt instrument, percentage points added to the reference rate			0.10%
GBX Leasing Warehouse Facility \| GBXL I Series 2022-1 Notes
Debt Instrument [Line Items]
Debt, Principal amount		$ 323.3
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			$ 262.6
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			$ 20.7
Debt instrument, interest rate			3.45%
GBX Leasing Warehouse Facility \| 2023 GBXL Notes
Debt Instrument [Line Items]
Debt, Principal amount	$ 178.5
Debt instrument, maturity month and year	2023-11
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			$ 153.7
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			$ 19.2
Debt instrument, interest rate			7.28%
Revolving Credit Facility \| North American
Debt Instrument [Line Items]
Line of credit facility maximum capacity			$ 600.0
Aggregate amount available to draw down			389.5
Letters of Credit Outstanding, Amount			$ 5.4	$ 5.9
Line of credit renewal month and year			2025-05
Revolving Credit Facility \| North American \| Maximum
Debt Instrument [Line Items]
Line of credit maturity date			2030-05
Revolving Credit Facility \| North American \| Minimum
Debt Instrument [Line Items]
Line of credit maturity date			2026-08
Revolving Credit Facility \| European
Debt Instrument [Line Items]
Line of credit facility maximum capacity			$ 98.3
Aggregate amount available to draw down			20.7
Revolving Credit Facility \| Mexico
Debt Instrument [Line Items]
Line of credit facility maximum capacity			156.0
Aggregate amount available to draw down			$ 86.0
Joint venture partner each guaranteed percentage			50.00%
Revolving Credit Facility \| Prime Rate \| North American
Debt Instrument [Line Items]
Debt instrument, percentage points added to the reference rate			0.50%
Revolving Credit Facility \| SOFR \| North American
Debt Instrument [Line Items]
Debt instrument, percentage points added to the reference rate			1.50%
Revolving Credit Facility \| SOFR Adjustment \| North American
Debt Instrument [Line Items]
Debt instrument, percentage points added to the reference rate			0.10%
Mexican Railcar Manufacturing Operations Line of Credit 2, 3rd Component of Senior Secured Credit Facilities \| Mexico
Debt Instrument [Line Items]
Debt instrument, percentage points added to the reference rate			1.96%
Mexican Railcar Manufacturing Operations Line of Credit 1, 3rd Component of Senior Secured Credit Facilities \| Mexico
Debt Instrument [Line Items]
Debt instrument, percentage points added to the reference rate			4.25%
Leasing Warehouse Credit Facility
Debt Instrument [Line Items]
Line of credit maturity date			2029-09
Swap agreement interest rate			91.00%
Leasing Warehouse Credit Facility \| North American
Debt Instrument [Line Items]
Line of credit facility maximum capacity			$ 450.0
Leasing Warehouse Credit Facility \| SOFR
Debt Instrument [Line Items]
Debt instrument, percentage points added to the reference rate			1.70%