Other Current Liabilities - Summary of changes in product warranties (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2018
Movement in Standard Product Warranty Accrual [Roll Forward]
Total product warranties – beginning of period	$ 54	$ 45
Accruals for product warranties	7	3
Payments	(5)	(4)
Change in estimates and other	(1)	1
Total product warranties – end of period	55	45
Less: Non-current product warranties	(36)	(29)	$ (35)
Product warranties – current	$ 19	$ 16	$ 19

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer) for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

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- Definition

Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

+ References

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- Definition

Amount of increase (decrease) in the standard and extended product warranty accrual from changes in estimates attributable to preexisting product warranties.

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Amount of increase in the standard and extended product warranty accrual from warranties issued.

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