Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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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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Segment Information - Segments Internal Financial Reports (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Feb. 28, 2018	Feb. 28, 2017	Feb. 28, 2018	Feb. 28, 2017	Aug. 31, 2017
Segment Reporting Information [Line Items]
Revenues	$ 629,336	$ 566,282	$ 1,188,871	$ 1,118,596
Earnings (loss) from operations	60,870	81,520	122,312	154,180
Assets	2,432,055		2,432,055		$ 2,397,705
Manufacturing
Segment Reporting Information [Line Items]
Revenues	511,827	445,504	963,312	899,537
Earnings (loss) from operations	63,185	85,369	116,154	168,710
Wheels & Parts
Segment Reporting Information [Line Items]
Revenues	88,710	82,714	166,721	152,349
Earnings (loss) from operations	5,119	5,569	7,537	8,463
Leasing & Services
Segment Reporting Information [Line Items]
Revenues	28,799	38,064	58,838	66,710
Earnings (loss) from operations	16,114	9,889	44,304	17,279
Operating Segments \| Manufacturing
Segment Reporting Information [Line Items]
Revenues	525,775	445,504	994,064	899,537
Earnings (loss) from operations	66,600	85,369	123,755	168,710
Assets	911,505		911,505		914,450
Operating Segments \| Wheels & Parts
Segment Reporting Information [Line Items]
Revenues	97,661	89,947	183,404	166,783
Earnings (loss) from operations	5,899	6,081	9,065	9,587
Assets	260,077		260,077		236,315
Operating Segments \| Leasing & Services
Segment Reporting Information [Line Items]
Revenues	33,164	40,176	64,808	74,156
Earnings (loss) from operations	19,908	11,813	49,470	24,453
Assets	565,626		565,626		535,323
Operating Segments \| Unallocated Amount to Segment
Segment Reporting Information [Line Items]
Assets	694,847		694,847		$ 711,617
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Earnings (loss) from operations	(23,548)	(19,307)	(45,683)	(40,272)
Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenues	(27,264)	(9,345)	(53,405)	(21,880)
Earnings (loss) from operations	(7,989)	(2,436)	(14,295)	(8,298)
Intersegment Eliminations \| Manufacturing
Segment Reporting Information [Line Items]
Revenues	(13,948)		(30,752)
Earnings (loss) from operations	(3,415)		(7,601)
Intersegment Eliminations \| Wheels & Parts
Segment Reporting Information [Line Items]
Revenues	(8,951)	(7,233)	(16,683)	(14,434)
Earnings (loss) from operations	(780)	(512)	(1,528)	(1,124)
Intersegment Eliminations \| Leasing & Services
Segment Reporting Information [Line Items]
Revenues	(4,365)	(2,112)	(5,970)	(7,446)
Earnings (loss) from operations	$ (3,794)	$ (1,924)	$ (5,166)	$ (7,174)