Condensed Consolidating Statement of Income (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
May 31, 2016	May 31, 2015	May 31, 2016	May 31, 2015
Revenue
Revenue	$ 612,866	$ 714,606	$ 2,084,334	$ 1,839,813
Cost of revenue
Cost of revenue	485,768	565,320	1,652,580	1,477,149
Margin	127,098	149,286	431,754	362,664
Selling and administrative expense	43,280	45,595	118,073	112,223
Net (gain) loss on disposition of equipment	(311)	(720)	(11,326)	(924)
Earnings from operations	84,129	104,411	325,007	251,365
Other costs
Interest and foreign exchange	3,712	4,285	10,565	9,355
Earnings (loss) before income taxes and earnings (loss) from unconsolidated affiliates	80,417	100,126	314,442	242,010
Income tax (expense) benefit	(22,449)	(30,783)	(92,902)	(76,209)
Earnings (loss) before earnings (loss) from unconsolidated affiliates	57,968	69,343	221,540	165,801
Earnings (loss) from unconsolidated affiliates	1,564	982	2,921	1,552
Net earnings (loss)	59,532	70,325	224,461	167,353
Net (earnings) loss attributable to noncontrolling interest	(24,180)	(27,514)	(74,808)	(41,405)
Net earnings (loss) attributable to Greenbrier	35,352	42,811	149,653	125,948
Manufacturing
Revenue
Revenue	458,494	593,376	1,611,686	1,478,566
Cost of revenue
Cost of revenue	352,775	465,658	1,247,635	1,184,922
Earnings from operations	92,713	115,675	325,215	258,602
Wheels & Parts
Revenue
Revenue	78,417	97,407	247,604	286,671
Cost of revenue
Cost of revenue	69,818	89,645	224,208	259,285
Earnings from operations	5,811	5,078	15,720	20,986
Leasing & Services
Revenue
Revenue	75,955	23,823	225,044	74,576
Cost of revenue
Cost of revenue	63,175	10,017	180,737	32,942
Earnings from operations	8,298	10,824	42,668	31,677
Parent
Revenue
Revenue	239	(90)	3,346	83
Cost of revenue
Margin	239	(90)	3,346	83
Selling and administrative expense	22,933	24,851	56,825	55,116
Earnings from operations	(22,694)	(24,941)	(53,479)	(55,033)
Other costs
Interest and foreign exchange	2,069	3,240	8,409	9,345
Earnings (loss) before income taxes and earnings (loss) from unconsolidated affiliates	(24,763)	(28,181)	(61,888)	(64,378)
Income tax (expense) benefit	1,460	4,215	(2,063)	(4,476)
Earnings (loss) before earnings (loss) from unconsolidated affiliates	(23,303)	(23,966)	(63,951)	(68,854)
Earnings (loss) from unconsolidated affiliates	58,655	66,777	213,604	194,802
Net earnings (loss)	35,352	42,811	149,653	125,948
Net earnings (loss) attributable to Greenbrier	35,352	42,811	149,653	125,948
Parent \| Manufacturing
Revenue
Revenue	(1,055)		1,992
Parent \| Leasing & Services
Revenue
Revenue	1,294	(90)	1,354	83
Combined Guarantor Subsidiaries
Revenue
Revenue	392,573	403,436	1,339,283	1,242,386
Cost of revenue
Cost of revenue	353,505	331,315	1,155,202	1,032,183
Margin	39,068	72,121	184,081	210,203
Selling and administrative expense	10,672	10,688	30,517	26,905
Net (gain) loss on disposition of equipment	(308)	(724)	(10,950)	(927)
Earnings from operations	28,704	62,157	164,514	184,225
Other costs
Interest and foreign exchange	1,910	1,649	5,182	4,998
Earnings (loss) before income taxes and earnings (loss) from unconsolidated affiliates	26,794	60,508	159,332	179,227
Income tax (expense) benefit	(7,556)	(26,025)	(52,706)	(62,438)
Earnings (loss) before earnings (loss) from unconsolidated affiliates	19,238	34,483	106,626	116,789
Earnings (loss) from unconsolidated affiliates	15,452	5,142	29,558	21,377
Net earnings (loss)	34,690	39,625	136,184	138,166
Net earnings (loss) attributable to Greenbrier	34,690	39,625	136,184	138,166
Combined Guarantor Subsidiaries \| Manufacturing
Revenue
Revenue	235,613	280,928	862,856	877,405
Cost of revenue
Cost of revenue	216,829	230,143	745,419	735,414
Combined Guarantor Subsidiaries \| Wheels & Parts
Revenue
Revenue	82,292	98,746	252,744	290,917
Cost of revenue
Cost of revenue	73,475	91,131	228,969	263,755
Combined Guarantor Subsidiaries \| Leasing & Services
Revenue
Revenue	74,668	23,762	223,683	74,064
Cost of revenue
Cost of revenue	63,201	10,041	180,814	33,014
Combined Non-Guarantor Subsidiaries
Revenue
Revenue	419,441	492,302	1,336,227	1,285,604
Cost of revenue
Cost of revenue	334,498	418,273	1,089,603	1,091,498
Margin	84,943	74,029	246,624	194,106
Selling and administrative expense	9,494	9,912	30,216	30,169
Net (gain) loss on disposition of equipment	254	7	256	7
Earnings from operations	75,195	64,110	216,152	163,930
Other costs
Interest and foreign exchange	(83)	(604)	(2,556)	(4,988)
Earnings (loss) before income taxes and earnings (loss) from unconsolidated affiliates	75,278	64,714	218,708	168,918
Income tax (expense) benefit	(15,244)	(7,888)	(38,171)	(22,559)
Earnings (loss) before earnings (loss) from unconsolidated affiliates	60,034	56,826	180,537	146,359
Earnings (loss) from unconsolidated affiliates	348	47	(16)	142
Net earnings (loss)	60,382	56,873	180,521	146,501
Net (earnings) loss attributable to noncontrolling interest	(22,579)	(26,415)	(76,023)	(61,992)
Net earnings (loss) attributable to Greenbrier	37,803	30,458	104,498	84,509
Combined Non-Guarantor Subsidiaries \| Manufacturing
Revenue
Revenue	419,441	492,302	1,336,226	1,285,603
Cost of revenue
Cost of revenue	334,498	418,273	1,089,603	1,091,498
Combined Non-Guarantor Subsidiaries \| Leasing & Services
Revenue
Revenue			1	1
Eliminations
Revenue
Revenue	(199,387)	(181,042)	(594,522)	(688,260)
Cost of revenue
Cost of revenue	(202,235)	(184,268)	(592,225)	(646,532)
Margin	2,848	3,226	(2,297)	(41,728)
Selling and administrative expense	181	144	515	33
Net (gain) loss on disposition of equipment	(257)	(3)	(632)	(4)
Earnings from operations	2,924	3,085	(2,180)	(41,757)
Other costs
Interest and foreign exchange	(184)		(470)
Earnings (loss) before income taxes and earnings (loss) from unconsolidated affiliates	3,108	3,085	(1,710)	(41,757)
Income tax (expense) benefit	(1,109)	(1,085)	38	13,264
Earnings (loss) before earnings (loss) from unconsolidated affiliates	1,999	2,000	(1,672)	(28,493)
Earnings (loss) from unconsolidated affiliates	(72,891)	(70,984)	(240,225)	(214,769)
Net earnings (loss)	(70,892)	(68,984)	(241,897)	(243,262)
Net (earnings) loss attributable to noncontrolling interest	(1,601)	(1,099)	1,215	20,587
Net earnings (loss) attributable to Greenbrier	(72,493)	(70,083)	(240,682)	(222,675)
Eliminations \| Manufacturing
Revenue
Revenue	(195,505)	(179,854)	(589,388)	(684,442)
Cost of revenue
Cost of revenue	(198,552)	(182,758)	(587,387)	(641,990)
Eliminations \| Wheels & Parts
Revenue
Revenue	(3,875)	(1,339)	(5,140)	(4,246)
Cost of revenue
Cost of revenue	(3,657)	(1,486)	(4,761)	(4,470)
Eliminations \| Leasing & Services
Revenue
Revenue	(7)	151	6	428
Cost of revenue
Cost of revenue	$ (26)	$ (24)	$ (77)	$ (72)

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