Stock options (Details 3) (USD $)	9 Months Ended
Jun. 30, 2012	Sep. 30, 2011
Option Outstanding and Exercisable
Number Outstanding	3,720,000
Remaining Average Contractual Life	9 years 6 months
Weighted Average Exercise Price	$ 4.12
Number Exercisable	116,666
Weighted Average Exercise Price	$ 4.23
Range 1 [Member]
Option Outstanding and Exercisable
Range of Exercise Price	4.68
Number Outstanding	75,000
Remaining Average Contractual Life	4 years 7 months 17 days
Weighted Average Exercise Price	$ 4.68
Number Exercisable
Weighted Average Exercise Price
Range 2 [Member]
Option Outstanding and Exercisable
Range of Exercise Price	4.25
Number Outstanding	385,000
Remaining Average Contractual Life	9 years 7 months 19 days
Weighted Average Exercise Price	$ 4.25
Number Exercisable	100,000
Weighted Average Exercise Price	$ 4.25
Range 3 [Member]
Option Outstanding and Exercisable
Range of Exercise Price	4.20
Number Outstanding	10,000
Remaining Average Contractual Life	9 years 8 months 23 days
Weighted Average Exercise Price	$ 4.20
Number Exercisable
Weighted Average Exercise Price
Range 4 [Member]
Option Outstanding and Exercisable
Range of Exercise Price	4.09
Number Outstanding	3,250,000
Remaining Average Contractual Life	9 years 7 months 17 days
Weighted Average Exercise Price	$ 4.09
Number Exercisable	16,666
Weighted Average Exercise Price	$ 4.09

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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.

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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

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

+ References

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

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