XML 36 R35.htm IDEA: XBRL DOCUMENT

Stock-Based Compensation (Schedule Of Valuation Assumptions) (Details)	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Stock-Based Compensation [Abstract]
Risk-free interest rate	0.70%	1.00%	1.60%
Expected volatility	38.00%	42.00%	56.00%
Expected life (years)	4 years 1 month 6 days	4 years 1 month 6 days	4 years 2 months 12 days
Dividend yield	0.00%	0.00%	0.00%

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.

+ References+ Details