Income Taxes - Classification of Deferred Income Tax Assets (Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Sep. 30, 2019	Dec. 29, 2018
Income Tax Disclosure [Abstract]
Non-current deferred income tax assets, net	$ 20		$ 72
Non-current deferred income tax liabilities, net	(47)	$ (45)	(16)
Net deferred income tax (liabilities) assets	$ (27)
Net deferred income tax (liabilities) assets			$ 56

Deferred Tax Assets, After Jurisdictional Netting, Noncurrent

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- Definition

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 6
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