Retirement Plan and Incentive Awards - Schedule of Stock Options and SSARs Outstanding and Related Activity (Details) (SSARs and Stock Options, USD $)	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
SSARs and Stock Options
Shares [Roll Forward]
Outstanding at beginning of period	560,784	429,973	375,248
Granted	161,010	160,651	109,507
Exercised	(2,788)	(681)	0
Expired	(55,811)	(22,914)	(10,948)
Forfeited	(12,972)	(6,245)	(43,834)
Outstanding at end of period	650,223	560,784	429,973
Exercisable at end of period	355,703	310,120	247,588
Vested or expected to vest in the future	649,773	558,519	428,597
Weighted-Average Exercise Price [Roll Forward]
Outstanding at beginning of period	$ 33.01	$ 48.80	$ 48.85
Granted	$ 19.11	$ 13.56	$ 10.80
Exercised	$ 14.29	$ 10.80	$ 0.00
Expired	$ 170.32	$ 47.65	$ 82.51
Forfeited	$ 19.85	$ 17.93	$ 24.13
Outstanding at end of period	$ 18.12	$ 33.01	$ 48.80
Exercisable at end of period	$ 19.74	$ 48.73	$ 58.61
Vested or expected to vest in the future	$ 18.12	$ 33.09	$ 40.88