COMMITMENTS AND CONTINGENCIES: (Details) (USD $)	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Lease Obligations
Rents charged to expense under operating leases	$ 5,200,000	$ 4,300,000
Minimum future lease commitments
2013	4,481,290
2014	3,373,977
2015	2,983,243
2016	2,453,104
2017	1,437,699
Thereafter	3,419,206
Total minimum lease payments	18,148,519
Self-insured liabilities reserve
Beginning balance	1,600,000	1,700,000
Charged to expense	5,100,000	4,400,000
Payments	5,300,000	4,500,000
Ending balance	$ 1,400,000	$ 1,600,000