Fair Value Of Financial Instruments (Financial Assets Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2012	Aug. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 13,180	$ 7,784
Restricted cash (current)	8,092	10,200
Restricted cash (noncurrent)	7,855	7,903
Total	29,127	25,887
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	13,180	7,784
Restricted cash (current)	8,092	10,200
Restricted cash (noncurrent)	7,855	7,903
Total	29,127	25,887
Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents
Restricted cash (current)
Restricted cash (noncurrent)
Total
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents
Restricted cash (current)
Restricted cash (noncurrent)
Total