Condensed Consolidating Balance Sheet (Detail) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2012	Aug. 31, 2012	Nov. 30, 2011	Aug. 31, 2011
Assets
Cash and cash equivalents	$ 41,284	$ 53,571	$ 20,855	$ 50,222
Restricted cash	7,322	6,277
Accounts receivable, net	163,385	146,326
Inventories	363,642	316,741
Leased railcars for syndication	54,297	97,798
Equipment on operating leases, net	362,522	362,968
Property, plant and equipment, net	186,715	182,429
Goodwill	137,066	137,066
Intangibles and other assets, net	79,500	81,368
Total assets	1,395,733	1,384,544
Liabilities and Equity
Revolving notes	89,826	60,755
Accounts payable and accrued liabilities	282,925	329,508
Deferred income taxes	96,498	95,363
Deferred revenue	28,283	17,194
Notes payable	427,697	428,079
Total equity Greenbrier	447,080	431,777
Noncontrolling interest	23,424	21,868
Total equity	470,504	453,645	382,940	375,901
Liabilities and Equity	1,395,733	1,384,544
Parent
Assets
Cash and cash equivalents	33,586	34,323	13,518	33,368
Accounts receivable, net	(4)	(21,666)
Property, plant and equipment, net	3,194	3,721
Intangibles and other assets, net	711,235	688,261
Total assets	748,011	704,639
Liabilities and Equity
Revolving notes	41,750
Accounts payable and accrued liabilities	(48,787)	(31,814)
Deferred income taxes	11,579	9,097
Deferred revenue	271	310
Notes payable	296,118	295,269
Total equity Greenbrier	447,080	431,777
Total equity	447,080	431,777
Liabilities and Equity	748,011	704,639
Combined Guarantor Subsidiaries
Assets
Cash and cash equivalents	14	294	232	529
Restricted cash	1,990	2,047
Accounts receivable, net	112,879	122,917
Inventories	181,066	138,236
Leased railcars for syndication	55,347	100,590
Equipment on operating leases, net	364,954	365,925
Property, plant and equipment, net	104,362	106,219
Goodwill	137,066	137,066
Intangibles and other assets, net	90,223	91,278
Total assets	1,047,901	1,064,572
Liabilities and Equity
Accounts payable and accrued liabilities	165,752	205,477
Deferred income taxes	94,937	96,593
Deferred revenue	27,476	15,970
Notes payable	129,925	130,953
Total equity Greenbrier	629,811	615,579
Total equity	629,811	615,579
Liabilities and Equity	1,047,901	1,064,572
Combined Non-Guarantor Subsidiaries
Assets
Cash and cash equivalents	7,684	18,954	7,105	16,325
Restricted cash	5,332	4,230
Accounts receivable, net	50,989	45,467
Inventories	182,895	178,810
Property, plant and equipment, net	79,159	72,489
Intangibles and other assets, net	3,105	3,620
Total assets	329,164	323,570
Liabilities and Equity
Revolving notes	48,076	60,755
Accounts payable and accrued liabilities	165,956	155,844
Deferred income taxes	(8,225)	(7,684)
Deferred revenue	521	901
Notes payable	1,654	1,857
Total equity Greenbrier	99,435	90,761
Noncontrolling interest	21,747	21,136
Total equity	121,182	111,897
Liabilities and Equity	329,164	323,570
Eliminations
Assets
Accounts receivable, net	(479)	(392)
Inventories	(319)	(305)
Leased railcars for syndication	(1,050)	(2,792)
Equipment on operating leases, net	(2,432)	(2,957)
Intangibles and other assets, net	(725,063)	(701,791)
Total assets	(729,343)	(708,237)
Liabilities and Equity
Accounts payable and accrued liabilities	4	1
Deferred income taxes	(1,793)	(2,643)
Deferred revenue	15	13
Total equity Greenbrier	(729,246)	(706,340)
Noncontrolling interest	1,677	732
Total equity	(727,569)	(705,608)
Liabilities and Equity	$ (729,343)	$ (708,237)