Investments (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Fair value method	$ 167	$ 662
Equity method	801	1,019
Cost method	2,492	2,056
Total Investments	3,460	3,737
Less: Current investments	137	602
Noncurrent investments	3,323	3,135
NBCUniversal Media, LLC [Member]
Fair value method	10	10
Equity method	626	840
Cost method	456	32
Total Investments	1,092	882
Air Touch [Member]
Cost method	1,579	1,568
Other Investment [Member]
Equity method	473	517
Cost method	913	488
Other Investment [Member] \| NBCUniversal Media, LLC [Member]
Equity method	298	338
The Weather Channel [Member]
Equity method	81	335
The Weather Channel [Member] \| NBCUniversal Media, LLC [Member]
Equity method	81	335
Hulu [Member]
Equity method	247	167
Hulu [Member] \| NBCUniversal Media, LLC [Member]
Equity method	$ 247	$ 167

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

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