INCOME TAXES Income Tax Effective Rate Reconciliation (Details)	12 Months Ended
Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2010
U.S. federal income tax rate	34.00%	34.00%	34.00%
Depletion deductions allowed for mining	(16.50%)	(8.70%)	(9.20%)
State income tax expense, net of federal tax expense	2.30%	2.90%	3.90%
Foreign tax restructuring	0.00%	0.80%	0.00%
Difference in effective tax rate of foreign subsidiaries	1.20%	(2.40%)	1.30%
Empowerment zone credits	(1.70%)	(1.20%)	(1.20%)
Valuation allowance increase (decrease)	11.40%	(1.70%)	(3.60%)
Other	(3.60%)	1.80%	1.00%
Effective Income Tax Rate	27.10%	25.50%	26.20%

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

+ References

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

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-Subparagraph (SAB TOPIC 6.I)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to changes in the valuation allowance for deferred tax assets.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the difference between statutory income tax rates in foreign jurisdictions and the domestic federal statutory income tax rate recorded during the period.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the different methods of depletion allowed under generally accepted accounting principles and enacted tax laws.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to all other items not otherwise listed in the existing taxonomy.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the state and local income tax expense or benefit, net of the federal tax benefit (expense) thereon, recorded during the period.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by foreign tax credits generated or utilized under enacted tax laws during the period.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by tax credits, not otherwise listed in the existing taxonomy, generated or utilized under enacted tax laws during the period.

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