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RELATED PARTIES (Summary Of Related Party Transactions Table Disclosure) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues | $ 534.1 | $ 555.6 | $ 743.2 | $ 157.0 | $ 696.3 | $ 741.8 | $ 714.3 | $ 180.0 | $ 1,989.9 | $ 2,332.4 | $ 1,866.0
Product [Member] |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |
Product revenues from related parties |  |  |  |  |  |  |  |  | 915.3 | 1,234.5 | 806.7
Revenues |  |  |  |  |  |  |  |  | $ 1,848.1 | $ 2,172.3 | $ 1,644.6
Related party product revenue as a percent of total product revenue |  |  |  |  |  |  |  |  | 49.50% | 56.80% | 49.10%

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