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Condensed Consolidated Financial Statement Details - Intangible Assets, Software and Impairments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Finite-Lived Intangible Assets [Line Items]
Amortization expense of intangible assets	$ 170	$ 182	$ 512	$ 547
Asset impairments	7	17	8	86
Termination Of Certain Internally Developed Software Projects
Finite-Lived Intangible Assets [Line Items]
Asset impairments	7		8
Certain Software Rendered Obsolete By the Company's Platform Modernization Initiatives
Finite-Lived Intangible Assets [Line Items]
Asset impairments		17
Real-Estate Related Assets
Finite-Lived Intangible Assets [Line Items]
Asset impairments				43
Non-Strategic Business
Finite-Lived Intangible Assets [Line Items]
Asset impairments				26
Property and Equipment
Finite-Lived Intangible Assets [Line Items]
Depreciation expense	41	41	124	142
Software
Finite-Lived Intangible Assets [Line Items]
Amortization expense	148	161	452	491
Platform Initiatives
Finite-Lived Intangible Assets [Line Items]
Software amortization expense	5	$ 14	18	$ 66
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, net	1,840		1,840
Trademarks and Other Intangible Assets
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, net	$ 107		$ 107