Current Assets and Current Liabilities (Details) (USD $)	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Receivables
Balance at beginning of year	$ 2,423,000	$ 2,938,000	$ 3,520,000
Charged to expense	1,302,000	532,000	1,008,000
Reclassified to assets held for sale	0	0	(826,000)
Accounts written off	(948,000)	(1,047,000)	(764,000)
Balance at end of year	2,777,000	2,423,000	2,938,000
Other Receivables
Allowance for other receivables	9,000,000
Reserve on note receivable and other contractual payments due from a specific buyer of some of the coal cleaning facilities (as a percent)	100.00%
Inventories
Raw materials	9,909,000	8,021,000
Finished goods	27,474,000	23,567,000
Inventories	37,383,000	31,588,000
Other Accrued Liabilities
Products and services received but not yet invoiced	24,355,000	22,183,000
Litigation	16,012,000	18,012,000
Other	14,901,000	10,751,000
Other Accrued Liabilities	$ 55,268,000	$ 50,946,000