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RELATED PARTIES - Summary Of Related Party Transactions Table Disclosure (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Related Party Transaction [Line Items] |  |  |
Revenue from related parties | $ 893 | $ 1,015 | $ 1,344
Revenues | $ 5,354 | $ 1,990 | $ 2,332
Related party product revenue as a percent of total product revenue | 16.70% | 51.00% | 57.60%
Purchases from related parties | $ 16 | $ 0 | $ 0
Realization of Deferred Revenue | $ 35 | $ 0 | $ 0

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- Definition Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07.1(c)) -URI http://asc.fasb.org/extlink&oid=120401555&loc=SL114874292-224272 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(e)) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 + Details
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