Summarized Financial Information for the Discontinued Operations (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended																12 Months Ended
	Jan. 31, 2012		Jul. 31, 2011		Apr. 30, 2011		Jan. 31, 2011		Oct. 31, 2010		Apr. 30, 2010		Jan. 31, 2010		Oct. 31, 2009		Jul. 31, 2012	Jul. 31, 2011		Jul. 31, 2010		Jul. 31, 2009		Oct. 31, 2011
Results of operations:
Net revenue																			[1]		[1]		[1]
Other income																	586					126	[1]
Total expenses																	(95)	(330)	[1]	(2,318)	[1]
Income (loss) from discontinued operations	670	[1]	(91)	[1]	(91)	[1]	(104)	[1]	(45)	[1]	(2,334)	[1]	(29)	[1]	45	[1]	491	(330)	[1]	(2,318)	[1]	126	[1]
Financial position:
Current assets
Current liabilities	(1,452)	[1]	(1,817)	[1]	(1,686)	[1]	(1,686)	[1]	(1,792)	[1]	(1,992)	[1]	(1,602)	[1]	(1,666)	[1]	(1,528)	(1,817)	[1]	(1,791)	[1]			(1,817)	[1]
Non-current liabilities	(983)	[1]	(1,883)	[1]	(2,241)	[1]	(2,587)	[1]	(2,929)	[1]	(3,575)	[1]	(2,057)	[1]	(2,235)	[1]	(293)	(1,883)	[1]	(3,289)	[1]			(1,623)	[1]
Net liabilities of discontinued operations			$ (3,700)														$ (1,821)	$ (3,700)		$ (5,080)

[1] As Restated