Condensed Consolidating Statement of Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		May 31, 2016	May 31, 2015	May 31, 2016	May 31, 2015
Condensed Statement of Income Captions [Line Items]
Net earnings (loss)		$ 59,532	$ 70,325	$ 224,461	$ 167,353
Other comprehensive income (loss)
Translation adjustment		1,477	(1,299)	(3,655)	(10,990)
Reclassification of derivative financial instruments recognized in net earnings (loss)	[1]	659	(254)	1,710	417
Unrealized gain (loss) on derivative financial instruments	[2]	1,113	107	(6,417)	(7)
Other (net of tax effect)		7	93	1	99
Other comprehensive income (loss)		3,256	(1,353)	(8,361)	(10,481)
Comprehensive income (loss)		62,788	68,972	216,100	156,872
Comprehensive (income) loss attributable to noncontrolling interest		(24,195)	(27,497)	(74,761)	(41,253)
Comprehensive income (loss) attributable to Greenbrier		38,593	41,475	141,339	115,619
Parent
Condensed Statement of Income Captions [Line Items]
Net earnings (loss)		35,352	42,811	149,653	125,948
Other comprehensive income (loss)
Translation adjustment				1,527
Unrealized gain (loss) on derivative financial instruments		5		(23)
Other comprehensive income (loss)		5		1,504
Comprehensive income (loss)		35,357	42,811	151,157	125,948
Comprehensive income (loss) attributable to Greenbrier		35,357	42,811	151,157	125,948
Combined Guarantor Subsidiaries
Condensed Statement of Income Captions [Line Items]
Net earnings (loss)		34,690	39,625	136,184	138,166
Other comprehensive income (loss)
Translation adjustment			(18)		(137)
Reclassification of derivative financial instruments recognized in net earnings (loss)		230	275	746	837
Unrealized gain (loss) on derivative financial instruments		3	(443)	(1,409)	(1,640)
Other comprehensive income (loss)		233	(186)	(663)	(940)
Comprehensive income (loss)		34,923	39,439	135,521	137,226
Comprehensive income (loss) attributable to Greenbrier		34,923	39,439	135,521	137,226
Combined Non-Guarantor Subsidiaries
Condensed Statement of Income Captions [Line Items]
Net earnings (loss)		60,382	56,873	180,521	146,501
Other comprehensive income (loss)
Translation adjustment		1,477	(1,281)	(3,655)	(10,853)
Reclassification of derivative financial instruments recognized in net earnings (loss)		429	(529)	964	(420)
Unrealized gain (loss) on derivative financial instruments		1,105	550	(4,985)	1,633
Other (net of tax effect)		7	93	1	99
Other comprehensive income (loss)		3,018	(1,167)	(7,675)	(9,541)
Comprehensive income (loss)		63,400	55,706	172,846	136,960
Comprehensive (income) loss attributable to noncontrolling interest		(22,594)	(26,398)	(75,976)	(61,840)
Comprehensive income (loss) attributable to Greenbrier		40,806	29,308	96,870	75,120
Eliminations
Condensed Statement of Income Captions [Line Items]
Net earnings (loss)		(70,892)	(68,984)	(241,897)	(243,262)
Other comprehensive income (loss)
Translation adjustment				(1,527)
Other comprehensive income (loss)				(1,527)
Comprehensive income (loss)		(70,892)	(68,984)	(243,424)	(243,262)
Comprehensive (income) loss attributable to noncontrolling interest		(1,601)	(1,099)	1,215	20,587
Comprehensive income (loss) attributable to Greenbrier		$ (72,493)	$ (70,083)	$ (242,209)	$ (222,675)

[1] Net of tax effect of $0.3 million and $0.04 million for the three months ended May 31, 2016 and 2015 and $0.7 million and $0.4 million for the nine months ended May 31, 2016 and 2015.

[2] Net of tax effect of $0.3 million and $0.1 million for the three months ended May 31, 2016 and 2015 and $2.2 million and $0.6 million for the nine months ended May 31, 2016 and 2015.