Common stock options granted, forfeited or expired and exercised - Stock-Based Compensation (Details 1) (USD $)	3 Months Ended
Oct. 31, 2014	Oct. 31, 2014	Aug. 02, 2014
Options
Options Outstanding		36,207,236	37,964,390
Options Forfeited or expired	1,215,000
Options Exercised	542,154
Options Exercisable	36,207,236
Weighted Average Exercise Price per Share
Weighted Average Exercise Price per Share		$ 0.040	$ 0.061
Weighted Average Exercise Price per Share, Forfeited or expired	$ 0.716
Weighted Average Exercise Price per Share, Exercised	$ 0.001
Weighted Average Exercise Price per Share, Exercisable	$ 0.040
Aggregate Intrinsic Vaalue
Options Outstanding		616,113
Options Exercised	9,488
Options Exercisable	616,113

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(3)-(4)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Weighted average price of options that were either forfeited or expired.

+ References

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-SubTopic 10

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-Paragraph 2

-Subparagraph (c)(1)(iv)(3)-(4)

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Topic 718

-SubTopic 10

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

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Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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