v3.20.4

Property, Plant And Equipment (Narrative) (Details) - USD ($) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Property, Plant and Equipment [Line Items] |  |  |  |
Depreciation expense |  | $ 20,277 | $ 20,285 | $ 20,083
Video | Communications |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Impairment charge recorded | $ 7,255 |  |  |
Video | Communications | Property, Plant and Equipment |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Impairment charge recorded | $ 1,681 |  |  |
Copper Network Assets |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Noncash pre-tax charge to abandon copper assets |  |  | 1,290 |
Software |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Depreciation expense |  | $ 3,483 | $ 3,313 | $ 3,092

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- Definition Amount of gain (loss) from the disposal of an asset through means other than sale, for example, but not limited to, abandonment, spin-off, and expropriation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2611-110228 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=108781800&loc=d3e2212-110226 + Details
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- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 + Details
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