XML 61 R68.htm IDEA: XBRL DOCUMENT

Fair Value of Employee Stock Purchase Plan with Weighted Average Assumptions (Detail) (Employee Stock Purchase Plan, USD $)	3 Months Ended		9 Months Ended
	Jun. 29, 2012	Jul. 01, 2011	Jun. 29, 2012	Jul. 01, 2011
Employee Stock Purchase Plan
Employee Stock Purchase Plan
Expected term (in years)	6 months	6 months	6 months	6 months
Risk-free interest rate	0.10%	0.10%	0.10%	0.20%
Expected volatility	18.00%	12.60%	20.60%	11.90%
Expected dividend	0.00%	0.00%	0.00%	0.00%
Weighted average fair value at grant date	$ 12.16	$ 13.09	$ 12.38	$ 11.91

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