Entity Central Index Key Interest and Foreign Exchange, Net Revenue and Cost of Revenue Lessee operating lease liability payments due after year four. Cover [Abstract] Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Entity Registrant Name Entity Registrant Name Trading Symbol Trading Symbol Security Exchange Name Security Exchange Name Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Current Reporting Status Entity Current Reporting Status Entity Interactive Data Current Entity Interactive Data Current Entity Filer Category Entity Filer Category Title of 12(b) Security Security12b Title Entity Common Stock, Shares Outstanding Entity Common Stock Shares Outstanding Document Quarterly Report Document Quarterly Report Document Transition Report Document Transition Report Entity File Number Entity File Number Entity Emerging Growth Company Entity Emerging Growth Company Entity Small Business Entity Small Business Entity Shell Company Entity Shell Company Entity Incorporation, State or Country Code Entity Incorporation State Country Code Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address Address Line1 Entity Address, Address Line Two Entity Address Address Line2 Entity Address, City or Town Entity Address City Or Town Entity Address, State or Province Entity Address State Or Province Entity Address, Postal Zip Code Entity Address Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Leased Railcars for Syndication, at Carrying Value Intangible Assets, Net And Other Assets (Excluding Goodwill) Statement Of Financial Position [Abstract] Assets Assets [Abstract] Cash and cash equivalents Cash And Cash Equivalents At Carrying Value Restricted cash Restricted Cash And Cash Equivalents Accounts receivable, net Accounts Receivable Net Income tax receivable Income Taxes Receivable Inventories Inventory Net Leased railcars for syndication Leased Railcars For Syndication At Carrying Value Equipment on operating leases, net Property Subject To Or Available For Operating Lease Net Property, plant and equipment, net Property Plant And Equipment Net Investment in unconsolidated affiliates Equity Method Investments Intangibles and other assets, net Intangible Assets Net And Other Assets Excluding Goodwill Goodwill Goodwill Total assets Assets Liabilities and Equity Liabilities And Stockholders Equity [Abstract] Revolving notes Line Of Credit Accounts payable and accrued liabilities Accounts Payable And Accrued Liabilities Current And Noncurrent Deferred income taxes Deferred Income Tax Liabilities Net Deferred revenue Deferred Revenue Notes payable, net Notes Payable Commitments and contingencies (Note 14) Commitments And Contingencies Contingently redeemable noncontrolling interest Redeemable Noncontrolling Interest Equity Carrying Amount Equity: Stockholders Equity Including Portion Attributable To Noncontrolling Interest [Abstract] Greenbrier Stockholders Equity [Abstract] Preferred stock - without par value; 25,000 shares authorized; none outstanding Preferred Stock Value Common stock - without par value; 50,000 shares authorized; 32,825 and 32,701 shares outstanding at February 28, 2021 and August 31, 2020 Common Stock Value Additional paid-in capital Additional Paid In Capital Common Stock Retained earnings Retained Earnings Accumulated Deficit Accumulated other comprehensive loss Accumulated Other Comprehensive Income Loss Net Of Tax Total equity – Greenbrier Stockholders Equity Noncontrolling interest Minority Interest Total equity Stockholders Equity Including Portion Attributable To Noncontrolling Interest Liabilities and Equity Liabilities And Stockholders Equity Preferred stock, without par value Preferred Stock No Par Value Preferred stock, shares authorized Preferred Stock Shares Authorized Preferred stock, outstanding Preferred Stock Shares Outstanding Common stock, without par value Common Stock No Par Value Common stock, shares authorized Common Stock Shares Authorized Common stock, shares outstanding Common Stock Shares Outstanding Income Loss From Continuing Operations After Income Taxes And Before Equity In Earnings Of Unconsolidated Affiliates Income Statement [Abstract] Statement [Table] Statement [Table] Segments Statement Business Segments [Axis] Segments Segment [Domain] Manufacturing. Manufacturing Manufacturing [Member] Wheels repair and parts. Wheels, Repair & Parts Wheels Repair And Parts [Member] Leasing and Services [Member] Leasing & Services Leasing And Services [Member] Statement [Line Items] Statement [Line Items] Revenue Revenues [Abstract] Revenue Revenue From Contract With Customer Excluding Assessed Tax Cost of revenue Cost Of Revenue [Abstract] Cost of revenue Cost Of Revenue Margin Gross Profit Selling and administrative expense Selling General And Administrative Expense Net gain on disposition of equipment Gain Loss On Sale Of Other Assets Earnings (loss) from operations Operating Income Loss Other costs Nonoperating Income Expense [Abstract] Interest and foreign exchange Interest And Foreign Exchange Net Earnings (loss) before income tax and earnings (loss) from unconsolidated affiliates Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments Income tax benefit (expense) Income Tax Expense Benefit Earnings (loss) before earnings (loss) from unconsolidated affiliates Income Loss From Continuing Operations After Income Taxes And Before Equity In Earnings Of Unconsolidated Affiliates Earnings (loss) from unconsolidated affiliates Income Loss From Equity Method Investments Net earnings (loss) Profit Loss Net (earnings) loss attributable to noncontrolling interest Net Income Loss Attributable To Noncontrolling Interest Net earnings (loss) attributable to Greenbrier Net Income Loss Basic earnings (loss) per common share Earnings Per Share Basic Diluted earnings (loss) per common share Earnings Per Share Diluted Weighted average common shares: Weighted Average Number Of Shares Outstanding [Abstract] Basic Weighted Average Number Of Shares Outstanding Basic Diluted Weighted Average Number Of Diluted Shares Outstanding Statement Of Income And Comprehensive Income [Abstract] Net earnings (loss) Other comprehensive income (loss) Other Comprehensive Income Loss Net Of Tax Period Increase Decrease [Abstract] Translation adjustment Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax Reclassification of derivative financial instruments recognized in net earnings (loss) Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax Unrealized loss on derivative financial instruments Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax Other (net of tax effect) Other Comprehensive Income Other Net Of Tax Other comprehensive income Other Comprehensive Income Loss Net Of Tax Comprehensive income (loss) Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest Comprehensive (income) loss attributable to noncontrolling interest Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest Comprehensive income (loss) attributable to Greenbrier Comprehensive Income Net Of Tax Reclassification of derivative financial instruments recognized in net earnings (loss), tax Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax Unrealized loss on derivative financial instruments, tax Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax Joint venture partner distribution declared Adjustments to Additional Paid in Capital, Unamortized Restricted Stock Statement Of Stockholders Equity [Abstract] Equity Components Statement Equity Components [Axis] Equity Component Equity Component [Domain] Common Stock Shares Common Stock [Member] Additional Paid-in Capital Additional Paid In Capital [Member] Retained Earnings Retained Earnings [Member] Accumulated Other Comprehensive (Loss) Accumulated Other Comprehensive Income [Member] Total Equity - Greenbrier Parent [Member] Noncontrolling Interest Noncontrolling Interest [Member] Equity Excluding Contingently Redeemable Noncontrolling Interest [Member] Equity Excluding Contingently Redeemable Noncontrolling Interest Equity Excluding Contingently Redeemable Noncontrolling Interest [Member] Redeemable Noncontrolling Interest [Member] Contingently Redeemable Noncontrolling Interest Redeemable Noncontrolling Interest [Member] Cumulative Effect, Period of Adoption Cumulative Effect Period Of Adoption [Axis] Cumulative Effect, Period of Adoption Cumulative Effect Period Of Adoption [Domain] Cumulative Effect Adjustment Due to Adoption Cumulative Effect Period Of Adoption Adjustment [Member] Beginning balance Beginning balance (in shares) Beginning balance Temporary Equity Carrying Amount Including Portion Attributable To Noncontrolling Interests Accounting Standards Update [Extensible List] Accounting Standards Update Extensible List Other comprehensive income (loss), net Noncontrolling interest adjustments Minority Interest Period Increase Decrease Joint venture partner distribution declared Joint Venture Partner Distribution Declared Noncontrolling interest acquired Noncontrolling Interest Increase From Business Combination Restricted stock awards (net of cancellations) Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures Restricted stock awards (net of cancellations) (in shares) Stock Issued During Period Shares Restricted Stock Award Net Of Forfeitures Unamortized restricted stock Adjustments To Additional Paid In Capital Unamortized Restricted Stock Restricted stock amortization Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value Cash dividends Dividends Cash Ending balance Ending Balance (in shares) Ending Balance Net earnings (loss) Temporary Equity Net Income Cash dividend per share Common Stock Dividends Per Share Declared Noncontrolling Interest Adjustments Increase Decrease in Leased Railcars for Syndication Payments for (proceeds from) interest in subsidiaries and affiliates. Proceeds From Unconsolidated affiliates and other. Transfer of leased railcars for syndication and inventories to equipment on operating leases. Dividends Declared And Accrued In Accounts Payable And Accrued Liabilities Debt Conversion of Unconsolidated Subsidiary Note Receivable To Investment In Unconsolidated Subsidiary. Accounts payable and accrued liabilities associated with cash distributions to joint venture partner Balance Sheet Reconciliation [Abstract] Statement Of Cash Flows [Abstract] Cash flows from operating activities Net Cash Provided By Used In Operating Activities Continuing Operations [Abstract] Adjustments to reconcile net earnings (loss) to net cash used in operating activities: Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities [Abstract] Deferred income taxes Deferred Income Tax Expense Benefit Depreciation and amortization Depreciation Depletion And Amortization Accretion of debt discount Accretion Expense Stock based compensation expense Share Based Compensation Noncontrolling interest adjustments Noncontrolling Interest Adjustments Other Other Operating Activities Cash Flow Statement Decrease (increase) in assets: Increase Decrease In Operating Assets [Abstract] Accounts receivable, net Increase Decrease In Accounts Receivable Income tax receivable Increase Decrease In Income Taxes Receivable Inventories Increase Decrease In Inventories Leased railcars for syndication Increase Decrease In Leased Railcars For Syndication Other assets Increase Decrease In Other Operating Assets Increase (decrease) in liabilities: Increase Decrease In Operating Liabilities [Abstract] Accounts payable and accrued liabilities Increase Decrease In Accounts Payable And Accrued Liabilities Deferred revenue Increase Decrease In Contract With Customer Liability Net cash used in operating activities Net Cash Provided By Used In Operating Activities Cash flows from investing activities Net Cash Provided By Used In Investing Activities Continuing Operations [Abstract] Proceeds from sales of assets Proceeds From Sale Of Property Plant And Equipment Capital expenditures Payments To Acquire Productive Assets Investments in and advances to / repayments from unconsolidated affiliates Payments For Proceeds From Interest In Subsidiaries And Affiliates Cash distribution from unconsolidated affiliates and other Proceeds From Unconsolidated Affiliates And Other Net cash provided by (used in) investing activities Net Cash Provided By Used In Investing Activities Cash flows from financing activities Net Cash Provided By Used In Financing Activities Continuing Operations [Abstract] Net change in revolving notes with maturities of 90 days or less Proceeds From Repayments Of Short Term Debt Maturing In Three Months Or Less Proceeds from revolving notes with maturities longer than 90 days Proceeds From Short Term Debt Maturing In More Than Three Months Repayments of revolving notes with maturities longer than 90 days Repayments Of Short Term Debt Maturing In More Than Three Months Repayments of notes payable Repayments Of Notes Payable Dividends Payments Of Dividends Cash distribution to joint venture partner Payments Of Distributions To Affiliates Tax payments for net share settlement of restricted stock Payments Related To Tax Withholding For Share Based Compensation Net cash used in financing activities Net Cash Provided By Used In Financing Activities Effect of exchange rate changes Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Decrease in cash and cash equivalents and restricted cash Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect Cash and cash equivalents and restricted cash Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents [Abstract] Cash and cash equivalents and restricted cash, Beginning balance Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Cash and cash equivalents and restricted cash, Ending balance Balance sheet reconciliation Balance Sheet Reconciliation [Abstract] Restricted cash Cash paid during the period for Supplemental Cash Flow Information [Abstract] Interest Interest Paid Net Income taxes, net Income Taxes Paid Net Non-cash activity Cash Flow Noncash Investing And Financing Activities Disclosure [Abstract] Transfer from Leased railcars for syndication and Inventories to Equipment on operating leases, net Transfer Of Leased Railcars For Syndication And Inventories To Equipment On Operating Leases Capital expenditures accrued in Accounts payable and accrued liabilities Capital Expenditures Incurred But Not Yet Paid Change in Accounts payable and accrued liabilities associated with dividends declared Dividends Declared And Accrued In Accounts Payable And Accrued Liabilities Conversion of unconsolidated affiliate note receivable to Investment in unconsolidated affiliates Debt Conversion Of Unconsolidated Subsidiary Note Receivable To Investment In Unconsolidated Subsidiary Change in Accounts payable and accrued liabilities associated with cash distributions to joint venture partner Accounts Payable And Accrued Liabilities Associated With Cash Distributions To Joint Venture Partner Organization Consolidation And Presentation Of Financial Statements [Abstract] Interim Financial Statements Organization Consolidation And Presentation Of Financial Statements Disclosure [Text Block] Revenue From Contract With Customer [Abstract] Revenue Recognition Revenue From Contract With Customer [Text Block] Inventory Disclosure [Abstract] Inventories Inventory Disclosure [Text Block] Goodwill And Intangible Assets Disclosure [Abstract]