Contingencies (Contingencies Narrative) (Details) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015 USD ($) $ / shares	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) item $ / shares	Jun. 30, 2014 USD ($)	Jan. 27, 2014 USD ($)
Loss Contingencies [Line Items]
Business Combination Contingent Consideration Arrangements, Contingent Value Right, Amount Per Share | $ / shares	$ 1.00		$ 1.00
Deductible related to litigation and contingent value right			$ 18
Contingent value right, percentage multiplier			90.00%
Number of contingent value rights outstanding | item			264,544,053
Amount which CVR holders are no longer entitled to payment	$ 312		$ 312
Contingent value right, period payable after final resolution			60 days
Business Combination, Contingent Consideration, Liability, Noncurrent	271		$ 271		$ 284
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability			(6)
Business Combination, Contingent Consideration, Liability, Current	2		2
Pending Litigation [Member] | Legal Matters Where Negative Outcome is Known or Probable [Member]
Loss Contingencies [Line Items]
Legal Fees	$ 2	$ 9	$ 6	$ 13
Class Action Shareholder Federal Securities Cases [Member] | Pending Litigation [Member] | Litigation Matters For Which An Outcome Cannot Be Assessed [Member]
Loss Contingencies [Line Items]
Number of legal cases filed | item			3
Shareholder Derivative Actions [Member] | Pending Litigation [Member] | Litigation Matters For Which An Outcome Cannot Be Assessed [Member]
Loss Contingencies [Line Items]
Number of legal cases filed | item			3