Consolidated Statements Of Stockholders Equity (USD $)	Common Stock [Member]	Additional Paid In Capital [Member]	Accumulated Deficit [Member]	Total
Stockholders' Equity, Beginning Balance at Jul. 31, 2010	$ 45,000	$ 50,609,000	$ (45,261,000)	$ 5,393,000
Beginning balance, Shares at Jul. 31, 2010	4,435,984
Issuance Of Common Stock In A Private Placement, Net, Shares	135,000
Issuance Of Common Stock In A Private Placement, Net, Value	1,000	2,366,000	0	2,367,000
Net loss	0	0	(8,349,000)	(8,349,000)
Issuance of common stock in a registered offering, net, shares	329,571
Issuance of common stock in a registered offering, net	3,000	3,062,000	0	3,065,000
Share-based compensation expense - stock options	0	1,010,000	0	1,010,000
Issuance of common stock upon exercise of stock options, shares	75,663
Share-based compensation expense - restricted stock	0	184,000	0	184,000
Share-based compensation expense - restricted stock, shares	12,637
Issuance of common stock upon exercise of stock options	1,000	277,000	0	278,000
Issuance of common stock upon exercise of warrants	0	259,000	0	259,000
Issuance of common stock upon exercise of warrants, shares	15,420
Stockholders' Equity, Ending Balance at Jul. 31, 2011	50,000	57,767,000	(53,610,000)	4,207,000
Ending balance, Shares at Jul. 31, 2011	5,004,275
Issuance Of Common Stock In A Private Placement, Net, Shares	575,125
Issuance Of Common Stock In A Private Placement, Net, Value	6,000	1,144,000	0	1,150,000
Net loss	0	0	(8,890,000)	(8,890,000)
Issuance of common stock in a registered offering, net, shares	167,136
Issuance of common stock in a registered offering, net	2,000	947,000	0	949,000
Share-based compensation expense - stock options	0	1,036,000	0	1,036,000
Share-based compensation expense - restricted stock	0	41,000	0	41,000
Share-based compensation expense - restricted stock, shares	6,852
Issuance Of Common Stock Under Purchase Plan, Value	7,000	1,712,000	0	1,719,000
Issuance Of Common Stock Under Purchase Plan, Shares	718,463
Issuance Of Common Stock Under Bridge Loan, Value	1,000	167,000	0	168,000
Issuance Of Common Stock Under Bridge Loan, Shares	55,503
Issuance of common stock for consulting agreements, shares	38,750
Issuance of common stock for consulting agreements	0	142,000	0	142,000
Commitment shares issued under purchase plan	1,000	295,000	0	296,000
Commitment shares issued under purchase plan, shares	78,451
Stockholders' Equity, Ending Balance at Jul. 31, 2012	$ 67,000	$ 63,251,000	$ (62,500,000)	$ 818,000
Ending balance, Shares at Jul. 31, 2012	6,644,555