XML 79 R90.htm IDEA: XBRL DOCUMENT

Weighted Average Assumptions Used in Determining Fair Value for Options Granted (Detail)	12 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected weighted average risk-free interest rate	2.43%	3.32%	3.40%
Expected weighted average life (in years)	6 years	6 years	10 years
Expected volatility	34.00%	34.00%	34.00%
Expected 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