Revenue Recognition - Disaggregation of Revenue by Geography (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue by Geography
Revenues	$ 73,620	$ 77,147	$ 79,591
Americas
Revenue by Geography
Revenues	34,114	36,274	36,994
EMEA
Revenue by Geography
Revenues	23,644	24,443	25,491
Asia Pacific
Revenue by Geography
Revenues	$ 15,863	$ 16,430	$ 17,106

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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+ Details