Interim Financial Statements	6 Months Ended
Feb. 29, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Interim Financial Statements	Note 1 – Interim Financial Statements The Condensed Consolidated Financial Statements of The Greenbrier Companies, Inc. and its subsidiaries (Greenbrier or the Company) as of February 29, 2020, for the three and six months ended February 29, 2020 and for the three and six months ended February 28, 2019 have been prepared to reflect all adjustments (consisting of normal recurring accruals) that, in the opinion of management, are necessary for a fair presentation of the financial position, operating results and cash flows for the periods indicated. The results of operations for the three and six months ended February 29, 2020 are not necessarily indicative of the results to be expected for the entire year ending August 31, 2020. Certain notes and other information have been condensed or omitted from the interim financial statements presented in this Quarterly Report on Form 10-Q. Therefore, these unaudited financial statements should be read in conjunction with the Consolidated Financial Statements contained in the Company’s 2019 Annual Report on Form 10-K. Management Estimates – The preparation of financial statements in conformity with accounting principles generally accepted in the U.S. requires judgment on the part of management to arrive at estimates and assumptions on matters that are inherently uncertain. These estimates may affect the amount of assets, liabilities, revenue and expenses reported in the financial statements and accompanying notes and disclosure of contingent assets and liabilities within the financial statements. Estimates and assumptions are periodically evaluated and may be adjusted in future periods. Actual results could differ from those estimates. Initial Adoption of Accounting Standards Lease accounting On September 1, 2019, the Company adopted Accounting Standards Update 2016-02, Leases (Topic 842). The new guidance supersedes existing guidance on accounting for leases in Topic 840 and is intended to increase the transparency and comparability of accounting for lease transactions. Topic 842 requires most leases to be recognized on the balance sheet by recording a right-of-use (ROU) asset and a lease liability. The liability will be equal to the present value of lease payments. The asset will be based on the liability, subject to adjustment, such as for initial direct costs. For income statement purposes, the FASB retained a dual model, requiring leases to be classified as either operating or finance. Lessor accounting remains similar to the prior model, but updated to align with certain changes to the lessee model and Topic 606: Contracts with Customers. The Company adopted the provisions of the new standard using the modified retrospective adoption method, utilizing the simplified transition option which allows entities to continue to apply the legacy guidance in Topic 840 in the comparative periods presented in the year of adoption. The Company elected the “package of practical expedients,” which allows it to not reassess under the new guidance prior conclusions about lease identification, lease classification, and initial direct costs. The Company did not elect the use-of-hindsight practical expedient. The Company elected to not separate lease and non-lease components. The Company elected the short-term lease recognition exemption for all leases that qualify, which means it will not recognize ROU assets or lease liabilities for leases with lease terms of less than twelve months. Following the adoption of Topic 842, the Company will utilize both Topic 842 and Topic 606: Contracts with Customers when evaluating retained risk of services and other performance obligations in conjunction with selling railcars with a lease attached as part of the syndication model. As a result of adoption, the Company recognized operating lease ROU assets and lease liabilities of $40.4 and $41.6 million, respectively, as of September 1, 2019. The Company also recognized an immaterial finance lease asset and corresponding lease liability. Additionally, the Company derecognized certain existing property, plant and equipment and deferred revenue for railcar transactions previously not qualifying as sales due to continuing involvement, that now qualify as sales under the new guidance. The gain associated with this change in accounting, was mostly offset by the recognition of a new guarantee liability. The adoption of this new standard also required the Company to eliminate deferred gains associated with certain sale-leaseback transactions. A cumulative-effect adjustment of $4.4 million was recorded as an increase to retained earnings as of September 1, 2019. Derivatives and Hedging In August 2017, the FASB issued Accounting Standards Update 2017-12, Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities (ASU 2017-12). This update improves the financial reporting of hedging relationships to better portray the economic results of an entity's risk management activities in its financial statements and make certain targeted improvements to simplify the application of the hedge accounting guidance. The guidance expands the ability to qualify for hedge accounting for non-financial and financial risk components, reduces complexity in fair value hedges of interest rate risk and eliminates the requirement to separately measure and report hedge ineffectiveness, as well as eases certain hedge effectiveness assessment requirements. The Company adopted this guidance effective September 1, 2019 and it did not have a material impact on our consolidated financial statements. Prospective Accounting Changes Measurement of Credit Losses on Financial Instruments In June 2016, the FASB issued Accounting Standard Update 2016-13, Financial Instruments – Credit Losses (ASU 2016-13). This update introduces a new model for recognizing credit losses on financial instruments based on an estimate of current expected credit losses. The new guidance will apply to loans, accounts receivable, trade receivables, other financial assets measured at amortized cost, loan commitments and other off-balance sheet credit exposures. The new guidance will also apply to debt securities and other financial assets measured at fair value through other comprehensive income. The new guidance is effective for annual reporting periods beginning after December 15, 2019, with early adoption permitted. The Company plans to adopt this guidance beginning September 1, 2020. The Company is currently evaluating the impact of this standard on its consolidated financial statements and disclosures.

Interim Financial Statements

6 Months Ended

Feb. 29, 2020

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Note 1 – Interim Financial Statements

The Condensed Consolidated Financial Statements of The Greenbrier Companies, Inc. and its subsidiaries (Greenbrier or the Company) as of February 29, 2020, for the three and six months ended February 29, 2020 and for the three and six months ended February 28, 2019 have been prepared to reflect all adjustments (consisting of normal recurring accruals) that, in the opinion of management, are necessary for a fair presentation of the financial position, operating results and cash flows for the periods indicated. The results of operations for the three and six months ended February 29, 2020 are not necessarily indicative of the results to be expected for the entire year ending August 31, 2020.

Certain notes and other information have been condensed or omitted from the interim financial statements presented in this Quarterly Report on Form 10-Q. Therefore, these unaudited financial statements should be read in conjunction with the Consolidated Financial Statements contained in the Company’s 2019 Annual Report on Form 10-K.

Management Estimates – The preparation of financial statements in conformity with accounting principles generally accepted in the U.S. requires judgment on the part of management to arrive at estimates and assumptions on matters that are inherently uncertain. These estimates may affect the amount of assets, liabilities, revenue and expenses reported in the financial statements and accompanying notes and disclosure of contingent assets and liabilities within the financial statements. Estimates and assumptions are periodically evaluated and may be adjusted in future periods. Actual results could differ from those estimates.

Initial Adoption of Accounting Standards

Lease accounting

On September 1, 2019, the Company adopted Accounting Standards Update 2016-02, Leases (Topic 842). The new guidance supersedes existing guidance on accounting for leases in Topic 840 and is intended to increase the transparency and comparability of accounting for lease transactions. Topic 842 requires most leases to be recognized on the balance sheet by recording a right-of-use (ROU) asset and a lease liability. The liability will be equal to the present value of lease payments. The asset will be based on the liability, subject to adjustment, such as for initial direct costs. For income statement purposes, the FASB retained a dual model, requiring leases to be classified as either operating or finance. Lessor accounting remains similar to the prior model, but updated to align with certain changes to the lessee model and Topic 606: Contracts with Customers.

The Company adopted the provisions of the new standard using the modified retrospective adoption method, utilizing the simplified transition option which allows entities to continue to apply the legacy guidance in Topic 840 in the comparative periods presented in the year of adoption. The Company elected the “package of practical expedients,” which allows it to not reassess under the new guidance prior conclusions about lease identification, lease classification, and initial direct costs. The Company did not elect the use-of-hindsight practical expedient. The Company elected to not separate lease and non-lease components. The Company elected the short-term lease recognition exemption for all leases that qualify, which means it will not recognize ROU assets or lease liabilities for leases with lease terms of less than twelve months. Following the adoption of Topic 842, the Company will utilize both Topic 842 and Topic 606: Contracts with Customers when evaluating retained risk of services and other performance obligations in conjunction with selling railcars with a lease attached as part of the syndication model.

As a result of adoption, the Company recognized operating lease ROU assets and lease liabilities of $40.4 and $41.6 million, respectively, as of September 1, 2019. The Company also recognized an immaterial finance lease asset and corresponding lease liability. Additionally, the Company derecognized certain existing property, plant and equipment and deferred revenue for railcar transactions previously not qualifying as sales due to continuing involvement, that now qualify as sales under the new guidance. The gain associated with this change in accounting, was mostly offset by the recognition of a new guarantee liability. The adoption of this new standard also required the Company to eliminate deferred gains associated with certain sale-leaseback transactions. A cumulative-effect adjustment of $4.4 million was recorded as an increase to retained earnings as of September 1, 2019.

Derivatives and Hedging

In August 2017, the FASB issued Accounting Standards Update 2017-12, Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities (ASU 2017-12). This update improves the financial reporting of hedging relationships to better portray the economic results of an entity's risk management activities in its financial statements and make certain targeted improvements to simplify the application of the hedge accounting guidance. The guidance expands the ability to qualify for hedge accounting for non-financial and financial risk components, reduces complexity in fair value hedges of interest rate risk and eliminates the requirement to separately measure and report hedge ineffectiveness, as well as eases certain hedge effectiveness assessment requirements. The Company adopted this guidance effective September 1, 2019 and it did not have a material impact on our consolidated financial statements.

Prospective Accounting Changes

Measurement of Credit Losses on Financial Instruments

In June 2016, the FASB issued Accounting Standard Update 2016-13, Financial Instruments – Credit Losses (ASU 2016-13). This update introduces a new model for recognizing credit losses on financial instruments based on an estimate of current expected credit losses. The new guidance will apply to loans, accounts receivable, trade receivables, other financial assets measured at amortized cost, loan commitments and other off-balance sheet credit exposures. The new guidance will also apply to debt securities and other financial assets measured at fair value through other comprehensive income. The new guidance is effective for annual reporting periods beginning after December 15, 2019, with early adoption permitted. The Company plans to adopt this guidance beginning September 1, 2020. The Company is currently evaluating the impact of this standard on its consolidated financial statements and disclosures.