Common Stock and Stock-Based Awards (Schedule of Nonvested Share Activity) (Details) (USD $)	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Common Stock and Stock-Based Awards [Abstract]
Nonvested at beginning of year	129,396	105,540	70,584
Granted	70,575	74,848	63,900
Vested	(44,547)	(48,072)	(25,934)
Forfeitures	(13,180)	(2,920)	(3,010)
Nonvested at end of year	142,244	129,396	105,540
Weighted average grant date fair value, Nonvested at beginning of year	$ 69.94	$ 61.69	$ 49.33
Weighted average grant date fair value, Granted	$ 145.65	$ 101.97	$ 71.14
Weighted average grant date fair value, Vested	$ 144.52	$ 102.09	$ 52.46
Weighted average grant date fair value, Forfeitures	$ 80.96	$ 63.49	$ 51.92
Weighted average grant date fair value, Nonvested at end of year	$ 83.13	$ 69.94	$ 61.69