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, 2013	Sep. 30, 2012	Sep. 30, 2011
SSARs and Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award, Ssars And Options, Exercisable Number	310,120	247,588	163,076
Shares [Roll Forward]
Outstanding at beginning of period	429,973	375,248	515,671
Granted	160,651	109,507	150,853
Expired	(22,914)	(10,948)	(148,393)
Forfeited	6,245	(43,834)	(142,883)
Outstanding at end of period	560,784	429,973	375,248
Vested or expected to vest in the future	558,519	428,597	367,693
Weighted-Average Exercise Price [Roll Forward]
Outstanding at beginning of period	$ 40.80	$ 48.85	$ 113.45
Granted	$ 13.56	$ 10.80	$ 23.45
Expired	$ 47.65	$ 82.51	$ 270.10
Forfeited	$ 17.93	$ 24.13	$ 25.45
Outstanding at end of period	$ 33.01	$ 40.80	$ 48.85
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	(681)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 10.80
Exercisable at end of period	$ 48.73	$ 58.61	$ 64.65
Vested or expected to vest in the future	$ 33.09	$ 40.88	$ 49.30