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

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

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+ 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

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

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Revenue Recognition Costs to Obtain or Fulfill a Contract (Details) - USD ($)	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Capitalized Contract Cost, Gross	$ 224,000,000		$ 224,000,000		$ 212,000,000
Capitalized Contract Cost, Amortization	47,000,000	$ 50,000,000	116,000,000	$ 119,000,000
Capitalized Contract Cost, Impairment Loss			0
Other Noncurrent Assets
Disaggregation of Revenue [Line Items]
Capitalized Contract Cost, Gross	103,000,000		103,000,000		102,000,000
Other Current Assets
Disaggregation of Revenue [Line Items]
Capitalized Contract Cost, Gross	$ 121,000,000		$ 121,000,000		$ 110,000,000