DEBT (Summary of Changes in Long-Term Debt) (Details) - USD ($) $ in Thousands		12 Months Ended
		Aug. 31, 2017		Aug. 31, 2016		Aug. 31, 2015
Debt Instrument [Line Items]
Current portion of long-term debt		$ 14,565
Long-term debt (net of current portion)		73,542
Total	[1]	88,107
Proceeds from long-term debt total		47,700		$ 14,370		$ 52,977
Repayment of long-term bank borrowings		(29,395)		(16,525)		$ (30,905)
Regularly scheduled loan payments, Current		(225)
Regularly scheduled loan payments, Noncurrent		15,837
Regularly scheduled loan payments total		(16,062)
Translation adjustments on foreign-currency debt of subsidiaries whose functional currency is not the U.S. dollar, Current	[2]	18
Translation adjustments on foreign-currency debt of subsidiaries whose functional currency is not the U.S. dollar, Noncurrent	[2]	(133)
Translation adjustments on foreign-currency debt of subsidiaries whose functional currency is not the U.S. dollar	[2]	(115)
Current portion of long-term debt		18,358		14,565
Long-term debt (net of current portion)		87,939		73,542
Total		106,297	[3]	88,107	[1]
Panama Subsidiary [Member]
Debt Instrument [Line Items]
Repayments of long-term debt, Current		(2,000)
Repayments of long-term debt, Noncurrent		(11,333)
Repayment of long-term bank borrowings		(13,333)
Trinidad Subsidiary [Member]
Debt Instrument [Line Items]
Proceeds from long-term debt incurred during the period, Current		6,000
Proceeds from long-term debt incurred during the period, Noncurrent		6,000
Proceeds from long-term debt total		12,000
Cash Asset [Member]
Debt Instrument [Line Items]
Debt Instrument, Collateral amount		0		0
NonCash Asset [Member]
Debt Instrument [Line Items]
Debt Instrument, Collateral amount		128,400		$ 102,400
Union Bank [Member]
Debt Instrument [Line Items]
Proceeds from long-term debt incurred during the period, Noncurrent		35,700
Proceeds from long-term debt total		$ 35,700

[1] The carrying amount on non-cash assets assigned as collateral for these loans was $102.4 million. No cash assets were assigned as collateral for these loans.

[2] These foreign currency translation adjustments are recorded within Other comprehensive income.

[3] The carrying amount on non-cash assets assigned as collateral for these loans was $128.4 million. No cash assets were assigned as collateral for these loans as of August 31, 2017.