The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the rights acquired through a franchise arrangement having an indefinite period of benefit.

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Goodwill and Other Intangible Assets (Goodwill) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 18, 2013
Goodwill [Line Items]
Indefinite-Lived License Agreements	$ 8,600	$ 8,600
Amortization of Intangible Assets	150us-gaap_AmortizationOfIntangibleAssets	115us-gaap_AmortizationOfIntangibleAssets	19us-gaap_AmortizationOfIntangibleAssets
Finite-Lived Intangible Assets, Gross	1,616	1,587
Finite-Lived Intangible Assets, Accumulated Amortization	(520)	(387)
Finite-Lived Intangible Assets, Net	1,096us-gaap_FiniteLivedIntangibleAssetsNet	1,200us-gaap_FiniteLivedIntangibleAssetsNet
Goodwill [Roll Forward]
Goodwill, Beginning Balance	14,365us-gaap_Goodwill	200us-gaap_Goodwill
Goodwill, Acquired During Period		14,165us-gaap_GoodwillAcquiredDuringPeriod
Goodwill, Other Changes	2us-gaap_GoodwillOtherChanges
Goodwill, Ending Balance	14,345us-gaap_Goodwill	14,365us-gaap_Goodwill	200us-gaap_Goodwill
SIRIUS XM
Goodwill [Line Items]
Indefinite-Lived Trade Names	930	930
Goodwill [Roll Forward]
Goodwill, Acquired During Period		14,165
Goodwill, Ending Balance	14,165	14,165
ANLBC
Goodwill [Line Items]
Indefinite-Lived Franchise Rights	143	143
Licensing Agreements [Member]
Goodwill [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years
Finite-Lived Intangible Assets, Gross	316	316
Finite-Lived Intangible Assets, Accumulated Amortization	(52)	(22)
Finite-Lived Intangible Assets, Net	264	294
Customer Relationships [Member]
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross	838	838
Finite-Lived Intangible Assets, Accumulated Amortization	(122)	(65)
Finite-Lived Intangible Assets, Net	716	773
Other Intangible Assets [Member]
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross	462	433
Finite-Lived Intangible Assets, Accumulated Amortization	(346)	(300)
Finite-Lived Intangible Assets, Net	116	133
Other Intangible Assets [Member] \| Corporate And Other
Goodwill [Roll Forward]
Goodwill, Beginning Balance	200
Goodwill, Other Changes	2
Goodwill, Ending Balance	180		200
Minimum \| Customer Relationships [Member]
Goodwill [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Maximum \| Customer Relationships [Member]
Goodwill [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years
Liberty Broadband
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	(46)
Liberty Broadband \| Other Intangible Assets [Member] \| Corporate And Other
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	(46)
SIRIUS XM
Goodwill [Roll Forward]
Goodwill, Beginning Balance				13,775
Goodwill, Ending Balance				13,775
TruePosition
Goodwill [Roll Forward]
Goodwill, Acquired During Period	24
TruePosition \| Other Intangible Assets [Member] \| Corporate And Other
Goodwill [Roll Forward]
Goodwill, Acquired During Period	$ 24