Summary of Significant Accounting Policies (Tables)

9 Months Ended

Jun. 30, 2013

Accounting Policies [Abstract]

Schedule of Computation of Basic and Diluted Net Income Per Share

The following table sets forth the computation of basic and diluted net income per share (in thousands, except per share data):

	Three months ended June 30,				Nine months ended June 30,
	2013		2012		2013		2012
Numerator
Net income	$	68,178	$	72,336	$	201,083	$	207,469
Denominator
Weighted average shares outstanding — basic	78,516		79,135		78,636		79,188
Dilutive effect of common shares from stock options and restricted stock units	348		520		571		646
Weighted average shares outstanding — diluted	78,864		79,655		79,207		79,834
Basic net income per share	$	0.87	$	0.91	$	2.56	$	2.62
Diluted net income per share	$	0.86	$	0.91	$	2.54	$	2.60