Discontinued Operations Assets and Liabilities Held for Sale (Details) - USD ($) $ in Millions	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Assets and Liabilities Held for Sale [Line Items]
Assets held for sale	$ 156	$ 147	$ 158
Building Solutions Asia Pacific \| Individually immaterial disposal group [Member]
Assets and Liabilities Held for Sale [Line Items]
Assets held for sale	$ 156	$ 147

Amount classified as assets attributable to disposal group held for sale or disposed of.

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