Goodwill - Schedule of Goodwill (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Oct. 01, 2019	Sep. 30, 2019
Goodwill [Line Items]
Indefinite-lived Intangible Assets (Excluding Goodwill)	$ 333		$ 333			$ 335
Goodwill [Roll Forward]
Goodwill, Beginning Balance			2,103
Goodwill, Ending Balance	1,476		1,476
Indefinite-lived Intangible Assets (Excluding Goodwill), Accumulated Impairment Loss	0		0			(2)
Indefinite-Lived Intangible Assets (Excluding Goodwill And Accumulated Impairment)	333		333			333
Intangible assets, net	2,720		2,720		$ 2,889	2,891
Accumulated impairment charges	(1,281)		(1,281)			(657)
Goodwill, Impairment Loss	(624)	$ 0	(624)	$ 0
Goodwill, Gross	2,757		2,757			2,760
Goodwill, Foreign Currency Translation Gain (Loss)			(3)
Products & Solutions
Goodwill [Roll Forward]
Goodwill, Beginning Balance			625
Goodwill, Ending Balance	0		0
Accumulated impairment charges	(1,281)		(1,281)			(657)
Goodwill, Impairment Loss			(624)
Goodwill, Gross	1,281		1,281			1,282
Goodwill, Foreign Currency Translation Gain (Loss)			(1)
Services
Goodwill [Roll Forward]
Goodwill, Beginning Balance			1,478
Goodwill, Ending Balance	1,476		1,476
Accumulated impairment charges	0		0			0
Goodwill, Impairment Loss			0
Goodwill, Gross	1,476		1,476			1,478
Goodwill, Foreign Currency Translation Gain (Loss)			(2)
Acquired Technology and Patents [Member]
Goodwill [Line Items]
Indefinite-lived Intangible Assets (Excluding Goodwill)	0		0			2
Goodwill [Roll Forward]
Indefinite-lived Intangible Assets (Excluding Goodwill), Accumulated Impairment Loss	0		0			(2)
Indefinite-Lived Intangible Assets (Excluding Goodwill And Accumulated Impairment)	0		0			0
Customer relationships and other intangibles
Goodwill [Line Items]
Indefinite-lived Intangible Assets (Excluding Goodwill)	0		0			0
Goodwill [Roll Forward]
Indefinite-lived Intangible Assets (Excluding Goodwill), Accumulated Impairment Loss	0		0			0
Indefinite-Lived Intangible Assets (Excluding Goodwill And Accumulated Impairment)	0		0			0
Trademarks and Trade Names [Member]
Goodwill [Line Items]
Indefinite-lived Intangible Assets (Excluding Goodwill)	333		333			333
Goodwill [Roll Forward]
Indefinite-lived Intangible Assets (Excluding Goodwill), Accumulated Impairment Loss	0		0			0
Indefinite-Lived Intangible Assets (Excluding Goodwill And Accumulated Impairment)	333		333			333
Trademarks and Trade Names [Member]
Goodwill [Roll Forward]
Intangible assets, net	359		359			364
Customer relationships and other intangibles
Goodwill [Roll Forward]
Intangible assets, net	1,795		1,795			1,875
Acquired Technology and Patents [Member]
Goodwill [Roll Forward]
Intangible assets, net	$ 566		$ 566			$ 652