CHANGES IN BUSINESS (Financial Information for Discontinued Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Feb. 28, 2018	Feb. 28, 2017	Feb. 28, 2018	Feb. 28, 2017	Aug. 31, 2017
Assets:
Assets of businesses held for sale & discontinued operations	$ 176,287		$ 176,287		$ 297,110
Liabilities:
Liabilities of businesses held for sale & discontinued operations	50,561		50,561		87,828
Income Statement Disclosures:
Earnings before income taxes	290	$ 9,591	8,410	$ 10,362
Structural Steel Fabrication Operations
Assets:
Accounts receivable	38,846		38,846		38,279
Inventories, net	8,311		8,311		10,676
Other current assets	35		35		77
Assets of businesses held for sale & discontinued operations	47,192		47,192		49,032
Liabilities:
Accounts payable-trade	15,667		15,667		13,108
Accrued expenses and other payables	10,424		10,424		16,785
Liabilities of businesses held for sale & discontinued operations	26,091		26,091		29,893
International Marketing and Distribution
Assets:
Accounts receivable	72,723		72,723		106,905
Inventories, net	49,106		49,106		141,135
Other current assets	6,934		6,934		38
Property, plant and equipment, net of accumulated depreciation and amortization	332		332		0
Assets of businesses held for sale & discontinued operations	129,095		129,095		248,078
Liabilities:
Accounts payable-trade	11,947		11,947		42,563
Accrued expenses and other payables	12,523		12,523		15,372
Liabilities of businesses held for sale & discontinued operations	24,470		24,470		57,935
Income Statement Disclosures:
Net sales	139,011	287,323	301,122	509,436
Cost of goods sold	130,687	265,380	272,138	471,919
Selling, general and administrative expenses	8,034	12,350	20,660	27,180
Interest expense	0	2	(86)	(25)
Earnings before income taxes	290	9,591	8,410	10,362
Income taxes (benefit)	(98)	2,251	3,082	2,433
Earnings from discontinued operations	$ 388	$ 7,340	$ 5,328	$ 7,929
Other Noncurrent Assets | Structural Steel Fabrication Operations
Assets:
Property, plant and equipment, net of accumulated depreciation and amortization					8,800
Other Noncurrent Assets | International Marketing and Distribution
Assets:
Property, plant and equipment, net of accumulated depreciation and amortization					$ 800