Segment Reporting - Reconciliation from Operating Income to Adjusted Operating Income (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Segment Reporting [Abstract]
Operating income	$ 3,577	$ 3,458
Amortization of intangible assets	587	586
Acquisition-related integration costs	41	69
Adjusted operating income (loss)	$ 4,205	$ 4,113

The net result for the period of deducting operating expenses from operating revenues.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8924-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Publisher FASB
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-Publisher FASB
-Name Accounting Standards Codification
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