Significant Transactions (Narrative) (Details) (USD $)	3 Months Ended
Mar. 31, 2013	Mar. 19, 2013
Significant Transactions [Line Items]
GE ownership percentage		49.00%
Purchase of NBCUniversal noncontrolling interest	$ 16,700,000,000
Payments related to acquisition of buildings	1,400,000,000
Preferred stock dividend rate percentage	5.25%
Deferred tax liabilities recognized associated with the redemption transaction	1,500,000,000
Cash On Hand
Significant Transactions [Line Items]
Total consideration transferred related to the Redemption Transaction and purchase of certain properties	11,400,000,000
NBCUniversal Enterprise Senior Unsecured Debt Securities
Significant Transactions [Line Items]
Total consideration transferred related to the Redemption Transaction and purchase of certain properties	4,000,000,000
Commercial Paper Program
Significant Transactions [Line Items]
Total consideration transferred related to the Redemption Transaction and purchase of certain properties	750,000,000
NBCUniversal Enterprise Credit Facility
Significant Transactions [Line Items]
Total consideration transferred related to the Redemption Transaction and purchase of certain properties	1,250,000,000
NBCUniversal Enterprise Preferred Stock
Significant Transactions [Line Items]
Total consideration transferred related to the Redemption Transaction and purchase of certain properties	$ 725,000,000

The total consideration associated with the purchase of GE's 49% noncontrolling common equity interest in NBCUniversal.

No definition available.

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- Definition

The amount of additional deferred tax liability recognized upon the purchase of a noncontrolling interest.

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No definition available.

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- Definition

The cash outflow for the purchase of certain properties at 30 Rockefeller Plaza and Englewood Cliffs associated with the NBCUniversal Transaction.

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No definition available.

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- Definition

The total consideration associated with the purchase of GE's 49% noncontrolling common equity interest in NBCUniversal related to the Redemption Transaction and the acquisition of certain properties at 30 Rockefeller Plaza and Engelwood Cliffs.

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No definition available.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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No definition available.

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

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No definition available.

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