Description Of Business And Significant Accounting Policies [Line Items]

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- Definition

Percentage of marketable securities investments mature with in one to two years.

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Percentage of marketable securities investments mature within one year.

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- Definition

Amount of allowance for credit loss on accounts receivable.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Topic 280
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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Description of Business and Significant Accounting Policies (Narrative) (Details) $ in Thousands	12 Months Ended
	Aug. 31, 2020 USD ($) Segment	Aug. 31, 2019 USD ($)	Aug. 31, 2018 USD ($)
Description Of Business And Significant Accounting Policies [Line Items]
Number of reportable segments \| Segment	2
Percentage of marketable securities investments mature within one year	64.00%
Percentage of marketable securities investments mature within one to two years	36.00%
Allowance for doubtful accounts	$ 2,800	$ 2,600
Impairments	$ 0	$ 0	$ 0
Building [Member] \| Minimum [Member]
Description Of Business And Significant Accounting Policies [Line Items]
Useful life	15 years
Building [Member] \| Maximum [Member]
Description Of Business And Significant Accounting Policies [Line Items]
Useful life	40 years
Equipment [Member] \| Minimum [Member]
Description Of Business And Significant Accounting Policies [Line Items]
Useful life	3 years
Equipment [Member] \| Maximum [Member]
Description Of Business And Significant Accounting Policies [Line Items]
Useful life	7 years
Leased Barrier Transfer Machines [Member] \| Minimum [Member]
Description Of Business And Significant Accounting Policies [Line Items]
Useful life	8 years
Leased Barrier Transfer Machines [Member] \| Maximum [Member]
Description Of Business And Significant Accounting Policies [Line Items]
Useful life	10 years
Computer Hardware and Software [Member] \| Minimum [Member]
Description Of Business And Significant Accounting Policies [Line Items]
Useful life	3 years
Computer Hardware and Software [Member] \| Maximum [Member]
Description Of Business And Significant Accounting Policies [Line Items]
Useful life	5 years
Leased Barriers [Member]
Description Of Business And Significant Accounting Policies [Line Items]
Useful life	12 years
Other [Member] \| Minimum [Member]
Description Of Business And Significant Accounting Policies [Line Items]
Useful life	2 years
Other [Member] \| Maximum [Member]
Description Of Business And Significant Accounting Policies [Line Items]
Useful life	20 years