Income Taxes (Details 1) (USD $)	12 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
The difference between the provision (benefit) for income taxes and the amount result from the application of the federal statutory rate to income before provision (benefit) for income taxes
Provision (benefit) for income taxes at statutory rate	$ 3,725,749	$ 4,090,069	$ 5,712,242
Percentage depletion	(846,040)	(733,516)	(684,053)
State income taxes, net of federal provision (benefit)	464,677	(92,989)	325,000
State net operating loss valuation allowance (release)	(31,000)	31,000	(278,000)
Other	(39,386)	(102,564)	(174,189)
provision (benefit) for income taxes	$ 3,274,000	$ 3,192,000	$ 4,901,000

The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Glossary Income Tax Expense (or Benefit)

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to changes in the valuation allowance for deferred tax assets in the period.

+ References

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to the different methods of depletion allowed under generally accepted accounting principles and enacted tax laws.

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The sum of other amounts reflected in the reconciliation of the statutory tax provision (benefit) to the actual tax provision (benefit).

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to state and local income tax expense or benefit.

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