DEBT (Summary of Changes in Long-Term Debt) (Details) - USD ($) $ in Thousands		9 Months Ended
		May 31, 2018	May 31, 2017	Aug. 31, 2017
Debt Instrument [Line Items]
Current portion of long-term debt		$ 18,358
Long-term debt (net of current portion)		87,939
Total	[1]	106,297
Proceeds from long-term debt total		28,500	$ 47,700
Regularly scheduled loan payments, Current		(3,739)
Regularly scheduled loan payments, Noncurrent		(9,829)
Regularly scheduled loan payments total		(13,568)
Reclassification of long-term debt, Current		2,479
Reclassification of long-term debt, Noncurrent		(2,479)
Translation adjustments on foreign-currency debt of subsidiaries whose functional currency is not the U.S. dollar, Current	[2]	146
Translation adjustments on foreign-currency debt of subsidiaries whose functional currency is not the U.S. dollar, Noncurrent	[2]	(160)
Translation adjustments on foreign-currency debt of subsidiaries whose functional currency is not the U.S. dollar total	[2]	(14)
Current portion of long-term debt		14,644
Long-term debt (net of current portion)		91,208
Total	[3]	105,852
Panama Subsidiary [Member]
Debt Instrument [Line Items]
Proceeds from long-term debt incurred during the period, Current		1,500
Proceeds from long-term debt incurred during the period, Noncurrent		13,500
Proceeds from long-term debt total		15,000
Honduras Subsidiary [Member]
Debt Instrument [Line Items]
Proceeds from long-term debt incurred during the period, Current		1,350
Proceeds from long-term debt incurred during the period, Noncurrent		12,150
Proceeds from long-term debt total		13,500
Trinidad Subsidiary [Member]
Debt Instrument [Line Items]
Repayments of long-term debt, Current		(3,000)
Repayments of long-term debt, Noncurrent		(3,000)
Repayments of long-term debt total		(6,000)
Cash Asset [Member]
Debt Instrument [Line Items]
Debt Instrument, Collateral amount		0		$ 0
NonCash Asset [Member]
Debt Instrument [Line Items]
Debt Instrument, Collateral amount		129,500		$ 128,400
Scotiabank [Member] | Honduras Subsidiary [Member]
Debt Instrument [Line Items]
Repayments of long-term debt, Current		(600)
Repayments of long-term debt, Noncurrent		(850)
Repayments of long-term debt total		(1,450)
Citibank [Member] | Honduras Subsidiary [Member]
Debt Instrument [Line Items]
Repayments of long-term debt, Current		(1,850)
Repayments of long-term debt, Noncurrent		(6,063)
Repayments of long-term debt total		$ (7,913)

[1] The carrying amount of non-cash assets assigned as collateral for these loans was $128.4 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 of non-cash assets assigned as collateral for these loans was $129.5 million. No cash assets were assigned as collateral for these loans.