NEW MARKETS TAX CREDIT TRANSACTIONS (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Feb. 28, 2017	Feb. 28, 2017	Aug. 31, 2016
Income Tax Contingency [Line Items]
Capital contribution received under new markets tax program		$ 17.7
Payments for qualified construction, development and equipping activities	$ 4.5	21.0
Restricted cash	0.7	0.7	$ 21.7
Commonwealth
Income Tax Contingency [Line Items]
Loans receivable	$ 35.3	$ 35.3
Loan receivable, interest rate	1.08%	1.08%
Investment Fund
Income Tax Contingency [Line Items]
Qualified equity investment into community development entities		$ 51.5
Qualified Equity Investment Loans \| CMC Steel Oklahoma, LLC
Income Tax Contingency [Line Items]
Loans payable	$ 50.7	$ 50.7

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Loan Receivable, Stated Interest Rate

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Qualified Equity Investment Into Community Development Entities

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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