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Stock-Based Compensation (Details) (USD $)	3 Months Ended
Stock-Based Compensation (Details) (USD $)	Jun. 30, 2013	Jun. 30, 2012
Employee Stock Options [Member]
Schedule of Weighted-Average Assumptions Used to Estimate the Fair Value of Stock Options
Expected life	4 years 4 months 24 days	4 years 6 months
Risk-free interest rate	0.60%	0.70%
Volatility	49.00%	54.00%
Dividend yield	0.00%	0.00%
Weighted average fair value	$ 2.95	$ 2.47
Employee Stock Purchase Plans [Member]
Schedule of Weighted-Average Assumptions Used to Estimate the Fair Value of Stock Options
Expected life	6 months	6 months
Risk-free interest rate	0.10%	0.10%
Volatility	50.00%	56.00%
Dividend yield	0.00%	0.00%
Weighted average fair value	$ 2.47	$ 2.40

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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