Reportable Segments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Segment Reporting [Abstract]
Interest expense	$ (93)us-gaap_InterestExpense	$ (93)us-gaap_InterestExpense
Interest income	5us-gaap_InvestmentIncomeNonoperating	3us-gaap_InvestmentIncomeNonoperating
Other items, net	(4)us-gaap_OtherNonoperatingIncomeExpense	5us-gaap_OtherNonoperatingIncomeExpense
Earnings from continuing operations before income taxes and equity in earnings (loss) of investee companies	610	706
Provision for income taxes	(203)us-gaap_IncomeTaxExpenseBenefit	(234)us-gaap_IncomeTaxExpenseBenefit
Equity in loss of investee companies, net of tax	(13)	(10)
Net earnings from continuing operations	394	462
Net earnings (loss) from discontinued operations, net of tax	0	6
Net earnings (loss)	394us-gaap_NetIncomeLoss	468us-gaap_NetIncomeLoss
Reportable Segments [Line Items]
Revenues	3,500us-gaap_Revenues	3,570us-gaap_Revenues
Operating income (loss)	702us-gaap_OperatingIncomeLoss	791us-gaap_OperatingIncomeLoss
Depreciation and amortization	68us-gaap_DepreciationAndAmortization	71us-gaap_DepreciationAndAmortization
Stock-based compensation	46us-gaap_ShareBasedCompensation	40us-gaap_ShareBasedCompensation
Capital expenditures	17	28
Assets	23,786us-gaap_Assets		24,072us-gaap_Assets
Operating Segments [Member] \| Entertainment Segment [Member]
Reportable Segments [Line Items]
Revenues	2,261	2,303
Operating income (loss)	346	420
Depreciation and amortization	32	37
Stock-based compensation	16	14
Capital expenditures	8	17
Assets	10,414		10,469
Operating Segments [Member] \| Cable Networks Segment [Member]
Reportable Segments [Line Items]
Revenues	539	537
Operating income (loss)	251	254
Depreciation and amortization	6	5
Stock-based compensation	3	2
Capital expenditures	1	2
Assets	2,136		2,113
Operating Segments [Member] \| Publishing Segment [Member]
Reportable Segments [Line Items]
Revenues	145	153
Operating income (loss)	12	11
Depreciation and amortization	1	2
Stock-based compensation	1	1
Capital expenditures	0	0
Assets	889		990
Operating Segments [Member] \| Local Broadcasting Segment [Member]
Reportable Segments [Line Items]
Revenues	596	626
Operating income (loss)	161	179
Depreciation and amortization	21	21
Stock-based compensation	7	7
Capital expenditures	7	8
Assets	9,495		9,585
Corporate [Member]
Reportable Segments [Line Items]
Operating income (loss)	(68)	(73)
Depreciation and amortization	8	6
Stock-based compensation	19	16
Capital expenditures	1	1
Assets	822		876
Corporate and Eliminations [Member]
Reportable Segments [Line Items]
Revenues	(41)	(49)
Intersegment Eliminations [Member]
Reportable Segments [Line Items]
Revenues	(43)	(49)
Intersegment Eliminations [Member] \| Entertainment Segment [Member]
Reportable Segments [Line Items]
Revenues	(40)	(46)
Intersegment Eliminations [Member] \| Local Broadcasting Segment [Member]
Reportable Segments [Line Items]
Revenues	(3)	(3)
Discontinued Operations [Member]
Reportable Segments [Line Items]
Assets	$ 30		$ 39

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