Stock-Based Compensation (Details 1) (USD $) In Thousands, except Per Share data, unless otherwise specified	6 Months Ended	12 Months Ended
Mar. 31, 2013	Sep. 30, 2012	Mar. 31, 2012	Sep. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Assumptions used to compute share-based compensation costs for the stock options granted
Shares purchased for offering period		8,052	44,666	52,762	43,335
Fair value per share	$ 0.65	$ 0.93	$ 0.69	$ 3.61	$ 3.98
Assumptions [Abstract]
Risk-free interest rate (average)	0.14%	0.14%	0.50%	0.12%	0.18%	0.50%	0.20%	0.30%
Expected dividend yield
Weighted average expected life (years)	6 months 0 days	6 months 0 days	6 months 0 days	6 months 0 days	6 months 0 days	4 years	1 year	1 year
Volatility (average)	74.00%	78.00%	105.00%	72.00%	72.00%	80.00%	73.00%	72.00%

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Share based compensation arrangement by share based payment award fair value assumptions fair value per share.

+ References

No definition available.

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- Definition

Weighted average expected term of share-based compensation awards, in 'PYMDTHMS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

The range of expected volatilities used and the weighted-average expected volatility for an entity using a valuation technique with different volatilities during the contractual term.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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