Income Taxes (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2009
Differences between the provision for income taxes and the Company's actual provision for income taxes
Federal statutory rate	(35.00%)	(34.00%)	(34.00%)
State income tax (benefit), net of federal benefit	(3.30%)	(3.50%)	0.00%
Foreign taxes	58.30%	(0.90%)	(1.20%)
Stock compensation and warrant expense	452.40%	6.00%	10.60%
Non-deductible expenses	(26.30%)	3.00%	(5.30%)
Research and developments credits	(900.10%)	(6.50%)	(8.60%)
Change in valuation allowance	(7114.10%)	38.10%	41.90%
Total provision for income taxes	(7568.10%)	2.20%	3.40%
Reconciliation of the beginning and ending amount of the consolidated liability for unrecognized tax benefits
Unrecognized Tax Benefits, Beginning Balance	$ 6,320	$ 5,124	$ 3,666
Additions for tax positions related to current year	4,478	1,212	1,458
Additions for tax positions related to prior year	119
Reductions for tax positions related to prior year	(129)	(16)
Unrecognized Tax Benefits, Ending Balance	$ 10,868	$ 6,320	$ 5,124

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to changes in the valuation allowance for deferred tax assets.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the difference between statutory income tax rates in foreign jurisdictions and the domestic federal statutory income tax rate recorded during the period.

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The sum of the differences between the effective income tax rate and domestic federal statutory income tax rate attributable to all nondeductible expenses under enacted tax laws.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to differences in the deductibility or nondeductibility of incentive stock options and other equity-based compensation costs in accordance with generally accepted accounting principles and enacted tax laws.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the state and local income tax expense or benefit, net of the federal tax benefit (expense) thereon, recorded during the period.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by research tax credits generated or utilized under enacted tax laws during the period.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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The gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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