XML 75 R54.htm IDEA: XBRL DOCUMENT
v3.21.2

Fair Value of Financial Instruments (Tables) | 12 Months Ended
--- | ---
Aug. 31, 2021
Fair Value Of Financial Instruments [Abstract] |
Estimated Fair Values of Financial Instruments and Methods and Assumptions Used | The estimated fair values of financial instruments and the methods and assumptions used to estimate such fair values are as follows:
(In thousands) |  | Carrying Amount 1 |  |  | Estimated Fair Value (Level 2) |
Notes payable as of August 31, 2021 |  | $ | 913,815 |  |  | $ | 935,917 |
Notes payable as of August 31, 2020 |  | $ | 832,126 |  |  | $ | 802,324 |
1 Carrying amount disclosed in this table excludes debt discount and debt issuance costs.

X
- Definition Fair Value of Financial Instruments [Abstract] + References No definition available. + Details
Name: | gbx_FairValueOfFinancialInstrumentsAbstract
Namespace Prefix: | gbx_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the fair value of financial instruments, including financial assets and financial liabilities, and the measurements of those instruments, assets, and liabilities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13467-108611 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueByBalanceSheetGroupingTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration