Segments Internal Financial Reports (Detail) - USD ($) $ in Thousands	3 Months Ended
Nov. 30, 2016	Nov. 30, 2015	Aug. 31, 2016
Segment Reporting Information [Line Items]
Revenues	$ 552,314	$ 802,389
Earnings (loss) from operations	72,660	148,485
Assets	1,817,350		$ 1,835,774
Manufacturing
Segment Reporting Information [Line Items]
Revenues	454,033	698,661
Earnings (loss) from operations	83,341	153,704
Wheels & Parts
Segment Reporting Information [Line Items]
Revenues	69,635	78,729
Earnings (loss) from operations	2,894	3,403
Leasing & Services
Segment Reporting Information [Line Items]
Revenues	28,646	24,999
Earnings (loss) from operations	7,390	9,958
Operating Segments \| Manufacturing
Segment Reporting Information [Line Items]
Revenues	454,033	698,661
Earnings (loss) from operations	83,341	153,704
Assets	729,361		701,296
Operating Segments \| Wheels & Parts
Segment Reporting Information [Line Items]
Revenues	76,836	85,545
Earnings (loss) from operations	3,506	4,087
Assets	279,971		275,599
Operating Segments \| Leasing & Services
Segment Reporting Information [Line Items]
Revenues	33,980	31,708
Earnings (loss) from operations	12,640	16,667
Assets	471,957		516,147
Operating Segments \| Unallocated Amount to Segment
Segment Reporting Information [Line Items]
Assets	336,061		$ 342,732
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Earnings (loss) from operations	(20,965)	(18,580)
Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenues	(12,535)	(13,525)
Earnings (loss) from operations	(5,862)	(7,393)
Intersegment Eliminations \| Wheels & Parts
Segment Reporting Information [Line Items]
Revenues	7,201	6,816
Earnings (loss) from operations	612	684
Intersegment Eliminations \| Leasing & Services
Segment Reporting Information [Line Items]
Revenues	5,334	6,709
Earnings (loss) from operations	$ 5,250	$ 6,709

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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+ 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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