Business Combination, Consideration Transferred, Capital Expenditures.

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Business Combination Description Of Voting Rights Acquired

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Number of railcar manufacturing facilities acquired.

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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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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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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.

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

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The net result for the period of deducting operating expenses from operating revenues.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Acquisitions - Additional Information (Detail) $ in Thousands		3 Months Ended		6 Months Ended
	Jul. 26, 2019 USD ($) Railcar	Feb. 29, 2020 USD ($)	Feb. 28, 2019 USD ($)	Feb. 29, 2020 USD ($)	Feb. 28, 2019 USD ($)
Business Acquisition [Line Items]
Revenue		$ 623,848	$ 658,671	$ 1,393,207	$ 1,263,194
Earnings (loss) from operations		38,436	18,054	80,220	54,508
Manufacturing
Business Acquisition [Line Items]
Revenue		489,943	476,019	1,147,310	947,808
Earnings (loss) from operations		46,105	$ 13,990	99,248	$ 50,845
American Railcar Industries
Business Acquisition [Line Items]
Business combination estimated gross purchase price	$ 417,200
Number of railcar manufacturing facilities acquired \| Railcar	2
Business combination consideration transferred for capital expenditures	$ 8,500
Senior term debt		300,000		300,000
Convertible senior notes		$ 50,000		$ 50,000
Business combination description of voting rights acquired				we did not acquire 100% of ARI
American Railcar Industries \| Manufacturing
Business Acquisition [Line Items]
Revenue				$ 210,700
Earnings (loss) from operations				$ (1,500)