Investments (Schedule of Investments) (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Schedule of Investments [Line Items]
Equity method	$ 5,719	$ 4,035
Marketable equity securities	577	341
Nonmarketable equity securities	2,057	1,805
Other investments	1,803	1,796
Total investments	10,156	7,977
Less: Current investments	1,718	94
Noncurrent investments	8,438	7,883
NBCUniversal Media LLC [Member]
Schedule of Investments [Line Items]
Equity method	1,342	707
Marketable equity securities	420	162
Nonmarketable equity securities	916	811
Total investments	2,678	1,680
Noncurrent investments	$ 2,678	$ 1,680

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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