Segment and Revenue Information (Revenues by Type) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 3,809	$ 3,466	$ 7,976	$ 7,227
Advertising [Member]
Disaggregation of Revenue [Line Items]
Revenues	1,424	1,327	3,468	3,060
Programming [Member]
Disaggregation of Revenue [Line Items]
Revenues	1,006	889	1,805	1,724
Publishing [Member]
Disaggregation of Revenue [Line Items]
Revenues	218	207	382	367
Affiliate and Subscription Fees [Member]
Disaggregation of Revenue [Line Items]
Revenues	1,113	989	2,224	1,968
Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 48	$ 54	$ 97	$ 108

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Name:	us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration