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Supplemental Information (Equity Method Investments) (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Schedule of Equity Method Investments [Line Items] |  |  |
Proceeds from equity method investments | $ (39) | $ 0 |
LACC, LLC |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Investments in and Advances to Affiliates, at Fair Value | 990 |  | $ 1,038
Proceeds from equity method investments | $ (39) |  |

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