Employee Share-Based Compensation (Details 2) - $ / shares	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
RSU
Restricted and Performance-Based Stock Unit Activity
Outstanding at beginning of period, number of shares	491,781	570,928	585,187
Granted, number of shares	139,387	161,835	180,036
Vested, number of shares	(189,841)	(205,599)	(157,039)
Forfeited, number of shares	(6,593)	(35,383)	(37,256)
Outstanding at end of period, number of shares	434,734	491,781	570,928
Outstanding at beginning of period, weighted average market price at grant	$ 55.81	$ 46.37	$ 38.47
Granted, weighted average market price at grant	87.63	68.13	63.19
Vested, weighted average market price at grant	47.3	39.93	37.37
Forfeited, weighted average market price at grant	62.83	52.17	41.49
Outstanding at end of period, weighted average market price at grant	$ 69.62	$ 55.81	$ 46.37
PSU
Restricted and Performance-Based Stock Unit Activity
Outstanding at beginning of period, number of shares	42,566	13,000	13,000
Granted, number of shares	37,004	43,466	0
Vested, number of shares	0	(13,000)	0
Forfeited, number of shares	0	(900)	0
Outstanding at end of period, number of shares	79,570	42,566	13,000
Outstanding at beginning of period, weighted average market price at grant	$ 66.63	$ 36.78	$ 36.78
Granted, weighted average market price at grant	86	66.63	0
Vested, weighted average market price at grant	0	36.78	0
Forfeited, weighted average market price at grant	0	66.64	0
Outstanding at end of period, weighted average market price at grant	$ 75.64	$ 66.63	$ 36.78