Reportable Segments (Assets) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Assets	$ 49,045	$ 49,519
Assets of discontinued operations	11	15
Assets held for sale	23	23
Operating Segments [Member] | TV Entertainment [Member]
Segment Reporting Information [Line Items]
Assets	19,260	19,689
Operating Segments [Member] | Cable Networks [Member]
Segment Reporting Information [Line Items]
Assets	22,220	22,109
Assets held for sale	23	23
Operating Segments [Member] | Filmed Entertainment [Member]
Segment Reporting Information [Line Items]
Assets	5,724	5,477
Operating Segments [Member] | Publishing [Member]
Segment Reporting Information [Line Items]
Assets	1,187	1,262
Corporate and Eliminations [Member]
Segment Reporting Information [Line Items]
Assets	$ 643	$ 967