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Stock-Based Compensation (Schedule of Assumptions Used in Estimate of Fair Value of Stock Option Awards) (Details) (Stock Options [Member])	3 Months Ended		9 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012 Minimum [Member]	Jun. 30, 2011 Minimum [Member]	Jun. 30, 2012 Maximum [Member]	Jun. 30, 2011 Maximum [Member]
Expected term	5 years 10 months 24 days	5 years 9 months 19 days	5 years 10 months 24 days	5 years 9 months 19 days	8 years 6 months	8 years 8 months 12 days
Estimated volatility	55.50%	53.70%	48.90%	48.00%	55.60%	54.00%
Estimated dividend yield	0.70%	1.00%	0.70%	1.00%	1.10%	1.30%
Risk-free interest rate	1.30%	1.80%	1.00%	1.80%	1.60%	2.60%

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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