Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Aug. 31, 2020	Aug. 31, 2019
Income Taxes [Line Items]
Valuation allowance	$ 3,218	$ 3,759
Unrecognized tax benefits that would impact effective tax rate	800	600
Accrued interest and penalties	$ 1,100	1,100
Maximum [Member]
Income Taxes [Line Items]
Percentage of Recognized largest amount benefit realized upon settlement	50.00%
Statutes of limitation range period	5 years
Minimum [Member]
Income Taxes [Line Items]
Statutes of limitation range period	3 years
Filtration Business [Member]
Income Taxes [Line Items]
Valuation allowance	$ 1,200	1,400
Certain Foreign Tax Jurisdiction [Member]
Income Taxes [Line Items]
Valuation allowance	$ 1,700	$ 2,400

Income taxes.

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- Definition

Percentage of Recognized largest amount benefit realized upon settlement

+ References

No definition available.

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Statutes of limitation range period.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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- Definition

Amount of expense for penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319

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