Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Feb. 29, 2020	Feb. 23, 2019	Feb. 29, 2020	Feb. 23, 2019	Aug. 31, 2019
Revenue From Contract With Customer [Abstract]
Percentage of revenues derived from route servicing fees	90.20%	91.00%	90.90%	91.00%
Current assets related to deferred commissions	$ 13.1		$ 13.1		$ 12.4
Noncurrent assets related to deferred commissions	54.3		54.3		$ 50.3
Amortization expense related to deferred commissions	$ 3.4	$ 2.9	$ 6.7	$ 5.7

Revenue From Contracts With Customers, Percentage Of Revenues From Route Servicing Fees

No definition available.

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- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

+ Details

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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as current.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

+ Details

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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as noncurrent.

+ References

+ Details

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- References

No definition available.

+ Details

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