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Investments - Schedule of Investments (Detail) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
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Equity Method Investments and Joint Ventures [Abstract] |  |
Equity method investments | $ 1,107 | $ 1,862
Private equity investments | 95 | 323
Other | 8 | 4
Investments | $ 1,210 | $ 2,189

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