v3.20.4

Revenue Recognition (Deferred Contract Acquisition and Fulfillment Costs) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Deferred Acquisition Costs |  |
Capitalized Contract Cost, Net [Abstract] |  |
Total deferred costs | $ 6,285 | $ 5,453
Deferred cost amortization | 2,755 | 2,174
Deferred Acquisition Costs | Other current assets |  |
Capitalized Contract Cost, Net [Abstract] |  |
Total deferred costs | 3,087 | 2,462
Deferred Acquisition Costs | Other Assets |  |
Capitalized Contract Cost, Net [Abstract] |  |
Total deferred costs | 3,198 | 2,991
Deferred Fulfillment Costs |  |
Capitalized Contract Cost, Net [Abstract] |  |
Total deferred costs | 9,752 | 10,958
Deferred cost amortization | 5,110 | 4,947
Deferred Fulfillment Costs | Other current assets |  |
Capitalized Contract Cost, Net [Abstract] |  |
Total deferred costs | 4,118 | 4,519
Deferred Fulfillment Costs | Other Assets |  |
Capitalized Contract Cost, Net [Abstract] |  |
Total deferred costs | $ 5,634 | $ 6,439

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- Definition Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054 + Details
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- Definition Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054 + Details
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