Reportable Segments (Schedule Of Revenues By Segment) (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
---|---|---|---|---|
Jun. 30, 2017 |
Jun. 30, 2016 |
Jun. 30, 2017 |
Jun. 30, 2016 |
|
Segment Reporting Information [Line Items] | ||||
Revenues by segment | $ 1,745 | $ 1,708 | $ 3,358 | $ 3,269 |
U.S. Networks [Member] | ||||
Segment Reporting Information [Line Items] | ||||
Revenues by segment | 890 | 873 | 1,719 | 1,680 |
International Networks [Member] | ||||
Segment Reporting Information [Line Items] | ||||
Revenues by segment | 811 | 790 | 1,558 | 1,501 |
Education And Other [Member] | ||||
Segment Reporting Information [Line Items] | ||||
Revenues by segment | 44 | 46 | 81 | 90 |
Corporate And Inter-Segment Eliminations [Member] | ||||
Segment Reporting Information [Line Items] | ||||
Revenues by segment | $ 0 | $ (1) | $ 0 | $ (2) |