Debt instrument, maturity year.

No definition available.

Name:	gbx_DebtInstrumentMaturityYear
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Period Type:	duration

- Definition

Debt instruments additional interest rate per annum.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

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+ Details

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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.

+ References

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

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Balance Type:	na
Period Type:	instant

- 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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+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

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+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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- Details

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- Details

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- Details

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Notes Payable, Net - Additional Information (Detail) - USD ($) $ in Millions		6 Months Ended
	Nov. 20, 2023	Feb. 29, 2024	Feb. 01, 2024	Aug. 31, 2023	Feb. 28, 2023
Debt Instrument [Line Items]
Debt instrument amount outstanding		$ 1,440.4		$ 1,329.9
Debt issuance costs, net		6.4		6.3
Leasing Nonrecourse Term Loans \| Nonrecourse Senior Term Debt
Debt Instrument [Line Items]
Debt, Principal amount		343.0
Debt instrument amount outstanding		326.6
Leasing Nonrecourse Term Loans \| Asset-Backed Term Notes
Debt Instrument [Line Items]
Debt, Principal amount		501.8
Debt instrument amount outstanding		$ 479.4
2.875% Convertible senior notes, due 2024
Debt Instrument [Line Items]
Convertible senior notes			$ 47.7	$ 47.7
Debt instrument, interest rate		2.875%		2.875%	2.875%
Debt instrument, maturity date		Feb. 01, 2024
GBX Leasing
Debt Instrument [Line Items]
Debt issuance costs, net	$ 2.2
GBX Leasing \| 2023 GBXL Notes
Debt Instrument [Line Items]
Debt, Principal amount	$ 178.5
Debt instrument, maturity year	2053
Debt instruments additional interest rate per annum	4.00%
GBX Leasing \| 2023 GBXL Notes \| GBXL I Series 2023-1 Class A Secured Railcar Equipment Notes
Debt Instrument [Line Items]
Debt, Principal amount	$ 158.9
Debt instrument, interest rate	6.42%
Debt instrument, maturity date	Nov. 20, 2053
GBX Leasing \| 2023 GBXL Notes \| GBXL I Series 2023-1 Class B Secured Railcar Equipment Notes
Debt Instrument [Line Items]
Debt, Principal amount	$ 19.6
Debt instrument, interest rate	7.28%
Debt instrument, maturity date	Nov. 20, 2053
GBX Leasing \| GBXL I Series 2022-1 Notes
Debt Instrument [Line Items]
Debt, Principal amount		$ 323.3