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Goodwill and Other Intangible Assets - Goodwill Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2022	Mar. 31, 2022	Sep. 30, 2021
Goodwill [Line Items]
Accumulated goodwill impairment	$ 706	$ 706	$ 471
Goodwill, Impairment Loss		235
Building Solutions North America
Goodwill [Line Items]
Goodwill, Impairment Loss		235
Building Solutions EMEA/LA
Goodwill [Line Items]
Goodwill, Impairment Loss		0
Building Solutions EMEA/LA \| Global Retail
Goodwill [Line Items]
Goodwill, Transfers		77
Building Solutions Asia Pacific
Goodwill [Line Items]
Goodwill, Impairment Loss		0
Building Solutions Asia Pacific \| Global Retail
Goodwill [Line Items]
Goodwill, Transfers		16
Building Solutions North America Retail [Member]
Goodwill [Line Items]
Accumulated goodwill impairment	659	659	424
Goodwill, Impairment Loss	235	235
Building Solutions EMEA/LA - Latin America [Member]
Goodwill [Line Items]
Accumulated goodwill impairment	$ 47	$ 47	$ 47