Stockholders' Equity (Details 2) (RSUs, USD $)	9 Months Ended
	Jun. 30, 2014
RSUs
Number of Shares
Balance unvested at the beginning of the period (in shares)	421,369
Granted (in shares)	293,992
Vested (in shares)	(69,994)
Forfeited (in shares)	(8,980)
Balance unvested at the end of the period (in shares)	636,387
Weighted Average Grant-Date Fair Value
Balance unvested at the beginning of the period (in dollars per share)	$ 43.76
Granted (in dollars per share)	$ 49.73
Vested (in dollars per share)	$ 43.76
Forfeited (in dollars per share)	$ 49.57
Balance unvested at the end of the period (in dollars per share)	$ 46.44