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Acquisitions and Divestitures (Acquisitions) (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	12 Months Ended			0 Months Ended
	Jun. 29, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2012
Consideration Transferred:
Total consideration transferred	$ 792	$ 0	$ 0	$ 792
Preliminary Purchase Price Allocation:
Goodwill		1,387us-gaap_Goodwill	1,409us-gaap_Goodwill	1,435us-gaap_Goodwill
Liabilities assumed in conjunction with the acquisition of businesses
Fair value of assets acquired		67us-gaap_FairValueOfAssetsAcquired	0us-gaap_FairValueOfAssetsAcquired	1,071us-gaap_FairValueOfAssetsAcquired
Fair value of consideration transferred for DJI business	792	0	0	792
Cash paid (net of cash acquired)		52us-gaap_TransferToInvestments	0us-gaap_TransferToInvestments	177us-gaap_TransferToInvestments
Liabilities assumed		15us-gaap_LiabilitiesAssumed1	0us-gaap_LiabilitiesAssumed1	102us-gaap_LiabilitiesAssumed1
Fair Value of S&P Index [Member]
Consideration Transferred:
Fair value of contribution	571
DJI [Member]
Consideration Transferred:
Total consideration transferred					792
Preliminary Purchase Price Allocation:
Current assets	79
Indefinite-lived intangibles	470
Goodwill	111
Current liabilities	(11)
Total net assets	792
Liabilities assumed in conjunction with the acquisition of businesses
Fair value of consideration transferred for DJI business					792
DJI [Member] \| Customer relationships
Preliminary Purchase Price Allocation:
Finite lived intangible assets	110
DJI [Member] \| Other Intangible Assets [Member]
Preliminary Purchase Price Allocation:
Finite lived intangible assets	33
DJI [Member] \| Fair Value of Noncontrolling interest of DJI [Member]
Consideration Transferred:
Fair value of contribution	$ 221