v3.20.4

Segment Information (Intersegment Assets, Equity Affiliates Investments and Capital Expenditures Details) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Assets	$ 525,761	$ 551,669
Investments in Equity Method Investees	1,780	3,695	$ 6,245
Capital Expenditures	15,675	19,635	$ 21,251
Corporate and eliminations
Segment Reporting Information [Line Items]
Assets	(163,755)	(133,681)
Investments in Equity Method Investees	67	34
Capital Expenditures	161	263
Communications | Operating Segments
Segment Reporting Information [Line Items]
Assets	522,758	521,252
Investments in Equity Method Investees	0	0
Capital Expenditures	14,107	17,410
WarnerMedia | Operating Segments
Segment Reporting Information [Line Items]
Assets	150,947	143,492
Investments in Equity Method Investees	1,123	3,011
Capital Expenditures	699	1,205
Latin America | Operating Segments
Segment Reporting Information [Line Items]
Assets	15,811	20,606
Investments in Equity Method Investees	590	650
Capital Expenditures	$ 708	$ 757

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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