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Investments (Tables) | 3 Months Ended
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Mar. 31, 2019
Investments [Line Items] |
Investment and Other Income (Loss), Net | Investment and Other Income (Loss), Net
| Three Months Ended March 31
(in millions) | 2019 |  | 2018
Equity in net income (losses) of investees, net | $ | 262 |  |  | $ | (49 | )
Realized and unrealized gains (losses) on equity securities, net | 214 |  |  | 28 |
Other income (loss), net | 200 |  |  | 147 |
Investment and other income (loss), net | $ | 676 |  |  | $ | 126 |
Investment Summary |
(in millions) | March 31, 2019 |  | December 31, 2018
Equity method | $ | 4,960 |  |  | $ | 4,035 |
Marketable equity securities | 538 |  |  | 341 |
Nonmarketable equity securities | 1,942 |  |  | 1,805 |
Other investments | 1,805 |  |  | 1,796 |
Total investments | 9,245 |  |  | 7,977 |
Less: Current investments | 86 |  |  | 94 |
Noncurrent investments | $ | 9,159 |  |  | $ | 7,883 |
NBCUniversal Media LLC [Member] |
Investments [Line Items] |
Investment and Other Income (Loss), Net | Investment and Other Income (Loss), Net
| Three Months Ended March 31
(in millions) | 2019 |  | 2018
Equity in net income (losses) of investees, net | $ | (120 | ) |  | $ | (100 | )
Realized and unrealized gains (losses) on equity securities, net | 161 |  |  | 37 |
Other income (loss), net | 199 |  |  | 59 |
Investment and other income (loss), net | $ | 240 |  |  | $ | (4 | )
Investment Summary |
(in millions) | March 31, 2019 |  | December 31, 2018
Equity method | $ | 831 |  |  | $ | 707 |
Marketable equity securities | 324 |  |  | 162 |
Nonmarketable equity securities | 912 |  |  | 811 |
Total investments | $ | 2,067 |  |  | $ | 1,680 |

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- Definition Tabular disclosure of investment and other income (loss), net, including, but not limited to, equity in net income (losses) of investees, net, realized and unrealized gains (losses) on equity securities, net, and other income (loss), net. + References No definition available. + Details
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- Definition Tabular disclosure of the summary of investment holdings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-12C) -URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611225-123010 + Details
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