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))
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
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Segments Internal Financial Reports (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Feb. 28, 2017	Feb. 29, 2016	Feb. 28, 2017	Feb. 29, 2016	Aug. 31, 2016
Segment Reporting Information [Line Items]
Revenues	$ 566,282	$ 669,079	$ 1,118,596	$ 1,471,468
Earnings (loss) from operations	81,520	92,393	154,180	240,878
Assets	2,155,978		2,155,978		$ 1,835,774
Manufacturing
Segment Reporting Information [Line Items]
Revenues	445,504	454,531	899,537	1,153,192
Earnings (loss) from operations	85,369	78,798	168,710	232,502
Wheels & Parts
Segment Reporting Information [Line Items]
Revenues	82,714	90,458	152,349	169,187
Earnings (loss) from operations	5,569	6,506	8,463	9,909
Leasing & Services
Segment Reporting Information [Line Items]
Revenues	38,064	124,090	66,710	149,089
Earnings (loss) from operations	9,889	24,412	17,279	34,370
Operating Segments \| Manufacturing
Segment Reporting Information [Line Items]
Revenues	445,504	454,531	899,537	1,153,192
Earnings (loss) from operations	85,369	78,815	168,710	232,519
Assets	724,209		724,209		701,296
Operating Segments \| Wheels & Parts
Segment Reporting Information [Line Items]
Revenues	89,947	97,658	166,783	183,203
Earnings (loss) from operations	6,081	7,267	9,587	11,354
Assets	280,207		280,207		275,599
Operating Segments \| Leasing & Services
Segment Reporting Information [Line Items]
Revenues	40,176	127,223	74,156	158,932
Earnings (loss) from operations	11,813	27,545	24,453	44,213
Assets	505,897		505,897		516,147
Operating Segments \| Unallocated Amount to Segment
Segment Reporting Information [Line Items]
Assets	645,665		645,665		$ 342,732
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Earnings (loss) from operations	(19,307)	(17,323)	(40,272)	(35,903)
Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenues	(9,345)	(10,333)	(21,880)	(23,859)
Earnings (loss) from operations	(2,436)	(3,911)	(8,298)	(11,305)
Intersegment Eliminations \| Manufacturing
Segment Reporting Information [Line Items]
Earnings (loss) from operations		17		17
Intersegment Eliminations \| Wheels & Parts
Segment Reporting Information [Line Items]
Revenues	7,233	7,200	14,434	14,016
Earnings (loss) from operations	512	761	1,124	1,445
Intersegment Eliminations \| Leasing & Services
Segment Reporting Information [Line Items]
Revenues	2,112	3,133	7,446	9,843
Earnings (loss) from operations	$ 1,924	$ 3,133	$ 7,174	$ 9,843