Sale Of Equipment Installment Receivables (Equipment Installment and WarnerMedia Programs) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding portfolio of receivables derecognized from our consolidated balance sheets	$ 9,713	$ 9,065
Cash proceeds received on finance receivables, net of remittances	7,211	6,508
Equipment Installment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross receivables:	4,576	5,994
Notes Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	2,467	3,457
Trade receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	477	438
Other Noncurrent Assets [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other Assets	1,632	2,099
WarnerMedia [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross receivables:	3,324	0
Outstanding portfolio of receivables derecognized from our consolidated balance sheets	4,300	0
Cash proceeds received on finance receivables, net of remittances	4,300	0
WarnerMedia [Member] \| Notes Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	0	0
WarnerMedia [Member] \| Trade receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	2,809	0
WarnerMedia [Member] \| Other Noncurrent Assets [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other Assets	$ 515	$ 0

The cummulative cash proceeds received, net of remittances (excluding amounts returned as deferred purchase price).

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Amount of assets classified as other.

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