Credit Arrangements (Details) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2011	Aug. 31, 2011
Debt Instrument [Line Items]
Long-term debt, including current maturities	$ 1,156,566	$ 1,226,405
Current maturities of long-term debt	3,697	58,908
Long-term debt	1,152,869	1,167,497
5.625% notes due November 2013 [Member]
Debt Instrument [Line Items]
Long-term debt, including current maturities	206,177	207,752
Weighted average Interest rate at 2011	3.80%
6.50% notes due July 2017 [Member]
Debt Instrument [Line Items]
Long-term debt, including current maturities	413,375	414,198
Weighted average Interest rate at 2011	5.00%
7.35% notes due August 2018 [Member]
Debt Instrument [Line Items]
Long-term debt, including current maturities	526,077	526,699
Weighted average Interest rate at 2011	5.60%
Other, including equipment notes [Member]
Debt Instrument [Line Items]
Long-term debt, including current maturities	10,937	10,632
CMCZ term note due May 2013 [Member]
Debt Instrument [Line Items]
Long-term debt, including current maturities	0	48,648
Weighted average Interest rate at 2011	0.00%
CMCS financing agreement due July 2014 [Member]
Debt Instrument [Line Items]
Long-term debt, including current maturities		$ 18,476

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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- Definition

Total of the portions of the carrying amounts as of the balance sheet date of long-term debt, which may include notes payable, bonds payable, debentures, mortgage loans, and commercial paper, which are scheduled to be repaid within one year or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

+ References

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

-Publisher SEC

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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Reflects the calculation as of the balance sheet date of the average interest rate weighted by the amount of long-term debt outstanding by type or by instrument at that time.

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