Consolidated Statement of Stockholders' Equity (Details) - USD ($)	3 Months Ended
	Nov. 30, 2015	Nov. 30, 2014	Aug. 31, 2015
Comprehensive income (loss)	$ (2,264,000)	$ (11,901,000)
Cash dividends paid on common stock, $0.205 per share	(6,024,000)
Cash dividends paid on convertible special stock, $15.00 per share	(1,875,000)	$ 0
Issuance of treasury stock	58,000
Stock options exercised	32,000
Amortization of restricted stock	724,000
Balance	(583,386,000)		$ (592,735,000)
Common Stock [Member]
Stock options exercised	2,000
Balance	(48,371,000)		(48,369,000)
Convertible special stock, no par value [Member]
Balance	(120,289,000)		(120,289,000)
Additional Paid-in Capital [Member]
Issuance of treasury stock	22,000
Stock options exercised	30,000
Amortization of restricted stock	724,000
Balance	(275,095,000)		(274,319,000)
Treasury Stock [Member]
Issuance of treasury stock	36,000
Balance	(383,085,000)		(383,121,000)
Accumulated Other Comprehensive Income (Loss) [Member]
Comprehensive income (loss)	(9,692,000)
Balance	93,152,000		83,460,000
Retained Earnings [Member]
Comprehensive income (loss)	7,093,000
Cash dividends paid on common stock, $0.205 per share	(6,024,000)
Cash dividends paid on convertible special stock, $15.00 per share	(1,875,000)
Balance	(606,884,000)		(607,690,000)
Noncontrolling Interest [Member]
Comprehensive income (loss)	335,000
Balance	$ (8,984,000)		$ (8,649,000)