Condensed Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Treasury Stock [Member]	Capital In Excess Of Stated Value [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) Income, Net [Member]
Beginning balance, value at Aug. 31, 2018	$ 276,866	$ 18,841	$ (277,238)	$ 68,465	$ 484,886	$ (18,088)
Beginning balance, shares at Aug. 31, 2018		18,841	8,083
Net earnings (loss)	(2,228)	$ 0	$ 0	0	(2,228)	0
Other comprehensive income (loss)	2,025	0	0	0	0	2,025
Total comprehensive income (loss)	(203)	0	0	0	0	0
Cash dividends per share	(6,688)	0	0	0	(6,688)	0
Issuance of common shares under share compensation plans, net, value	(947)	$ 29	$ 0	(976)	0	0
Issuance of common shares under share compensation plans, net, shares		29	0
Share-based compensation expense	2,283	$ 0	$ 0	2,283	0	0
Cumulative impact of ASC/ASU adoption \| ASC 606 [Member]	532	0	0	0	532	0
Cumulative impact of ASC/ASU adoption \| ASU 2018-02 [Member]	0	0	0	0	525	(525)
Ending balance, value at Feb. 28, 2019	271,843	$ 18,870	$ (277,238)	69,772	477,027	(16,588)
Ending Balance, shares at Feb. 28, 2019		18,870	8,083
Beginning balance, value at Nov. 30, 2018	276,675	$ 18,870	$ (277,238)	68,710	483,811	(17,478)
Beginning balance, shares at Nov. 30, 2018		18,870	8,083
Net earnings (loss)	(3,440)	$ 0	$ 0	0	(3,440)	0
Other comprehensive income (loss)	890	0	0	0	0	890
Total comprehensive income (loss)	(2,550)	0	0	0	0	0
Cash dividends per share	(3,344)	0	0	0	(3,344)	0
Issuance of common shares under share compensation plans, net, value	(4)	$ 0	$ 0	(4)	0	0
Issuance of common shares under share compensation plans, net, shares		0	0
Share-based compensation expense	1,066	$ 0	$ 0	1,066	0	0
Ending balance, value at Feb. 28, 2019	271,843	$ 18,870	$ (277,238)	69,772	477,027	(16,588)
Ending Balance, shares at Feb. 28, 2019		18,870	8,083
Beginning balance, value at Aug. 31, 2019	268,209	$ 18,870	$ (277,238)	71,684	474,740	(19,847)
Beginning balance, shares at Aug. 31, 2019		18,870	8,083
Net earnings (loss)	13,861	$ 0	$ 0	0	13,861	0
Other comprehensive income (loss)	(1,041)	0	0	0	0	(1,041)
Total comprehensive income (loss)	12,820	0	0	0	0	0
Cash dividends per share	(6,711)	0	0	0	(6,711)	0
Issuance of common shares under share compensation plans, net, value	434	$ 48	$ 0	386	0	0
Issuance of common shares under share compensation plans, net, shares		48	0
Share-based compensation expense	2,575	$ 0	$ 0	2,575	0	0
Ending balance, value at Feb. 29, 2020	277,327	$ 18,918	$ (277,238)	74,645	481,890	(20,888)
Ending Balance, shares at Feb. 29, 2020		18,918	8,083
Beginning balance, value at Nov. 30, 2019	273,000	$ 18,897	$ (277,238)	71,706	479,732	(20,097)
Beginning balance, shares at Nov. 30, 2019		18,897	8,083
Net earnings (loss)	5,516	$ 0	$ 0	0	5,516	0
Other comprehensive income (loss)	(791)	0	0	0	0	(791)
Total comprehensive income (loss)	4,725	0	0	0	0	0
Cash dividends per share	(3,358)	0	0	0	(3,358)	0
Issuance of common shares under share compensation plans, net, value	1,545	$ 21	$ 0	1,524	0	0
Issuance of common shares under share compensation plans, net, shares		21	0
Share-based compensation expense	1,415	$ 0	$ 0	1,415	0	0
Ending balance, value at Feb. 29, 2020	$ 277,327	$ 18,918	$ (277,238)	$ 74,645	$ 481,890	$ (20,888)
Ending Balance, shares at Feb. 29, 2020		18,918	8,083

Cumulative effects adjustment from adoption of new accounting standards.

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Amount of increase to additional paid-in capital (APIC) for recognition of cost for award under share-based payment arrangement.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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