Intangible Assets Including Goodwill - Goodwill by Segment (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Changes in Goodwill Balances
Beginning Balance	$ 1,230
Ending Balance	1,201	$ 1,230
Goodwill impairment losses	0	0
Goodwill accumulated impairment losses	0	0
Business Segments
Changes in Goodwill Balances
Beginning Balance	1,230	1,162
Foreign Currency Translation and Other Adjustments	(29)	67
Ending Balance	1,201	1,230
Business Segments \| Americas
Changes in Goodwill Balances
Beginning Balance	440	416
Foreign Currency Translation and Other Adjustments	(8)	24
Ending Balance	431	440
Business Segments \| EMEA
Changes in Goodwill Balances
Beginning Balance	288	272
Foreign Currency Translation and Other Adjustments	4	16
Ending Balance	292	288
Business Segments \| Japan
Changes in Goodwill Balances
Beginning Balance	424	401
Foreign Currency Translation and Other Adjustments	(9)	23
Ending Balance	415	424
Business Segments \| Asia Pacific
Changes in Goodwill Balances
Beginning Balance	78	74
Foreign Currency Translation and Other Adjustments	(16)	4
Ending Balance	$ 62	$ 78

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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