Credit Losses on Financial Instruments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance at December 31, 2021	$ 114
Provision for expected losses	25
Write-offs charged against the allowance	(35)
Recoveries collected	4
Change in allowance in assets held for sale	3
Ending balance at March 21, 2022	111
Disposal Group, Held-for-sale, Not Discontinued Operations
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for doubtful accounts	21	$ 24
Business
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance at December 31, 2021	88
Provision for expected losses	8
Write-offs charged against the allowance	(13)
Recoveries collected	3
Change in allowance in assets held for sale	(1)
Ending balance at March 21, 2022	85
Mass Markets
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance at December 31, 2021	26
Provision for expected losses	17
Write-offs charged against the allowance	(22)
Recoveries collected	1
Change in allowance in assets held for sale	4
Ending balance at March 21, 2022	$ 26