Income Taxes - Uncertain Tax Positions (Details) - USD ($) $ in Thousands	12 Months Ended
	Aug. 31, 2020	Aug. 31, 2019	Aug. 31, 2018
Deferred tax assets:
Allowance for doubtful accounts	$ 309	$ 432
Inventories	994	1,193
Accruals	504	541
Warranty reserve	14	22
Pension accrual	2,749	2,623
Deferred compensation	391	300
Foreign currency loss on previously taxed income	96	96
Loan finance costs	7	34
Restricted stock grants	823	456
Non-qualified stock options	211	258
Right-of-use asset	2,354
Foreign net operating loss, net of valuation allowance	247
Other	572	353
Deferred tax assets, net	9,271	6,308
Deferred tax liabilities:
Prepaid liabilities	(16)	(8)
Lease liability	(2,693)
Depreciation and amortization	(1,633)	(2,496)
Noncurrent deferred tax liabilities	(4,342)	(2,504)
Net deferred tax assets (liabilities)	4,929	3,804
Gross foreign operating loss carry forwards	727
Adjustments to uncertain tax positions
Balance, at beginning of the year	2,324	1,889	$ 1,257
Increase for tax positions related to the current year	101	55	47
(Decrease) increase for tax positions related to prior years	(609)	300	595
Increase for interest and penalties	125	106	71
Decrease for lapses of statute of limitations		(26)	(81)
Balance, at end of year	1,941	$ 2,324	$ 1,889
Accrued balances related to uncertain tax positions
Accrued interest and penalty	1,002
Increase in accrued interest and penalty charges recorded as tax benefit	$ 125