Acquisitions (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Business Acquisition [Line Items]
Benefit related to change in fair value of contingent liability	$ 23
Contingent payment related to business combination	0
R&D- and commercialization-based milestones [Member]
Business Acquisition [Line Items]
Business Acquisition, Contingent Consideration, at Fair Value	199
revenue-based payments [Member] | Monte Carlo [Member]
Business Acquisition [Line Items]
Business Acquisition, Contingent Consideration, at Fair Value	240
Revenue Volatility - Contingent Consideration	15.00%
contingent consideration liability, probability of payment	29.00%
revenue-based payments [Member] | Discounted cash flow [Member]
Business Acquisition [Line Items]
Business Acquisition, Contingent Consideration, at Fair Value	$ 203
Maximum [Member] | R&D- and commercialization-based milestones [Member]
Business Acquisition [Line Items]
Risk-adjusted discount rate for contingent consideration	2.40%
contingent consideration liability, probability of payment	98.00%
contingent consideration liability, projected year of payment	2017
Maximum [Member] | revenue-based payments [Member] | Monte Carlo [Member]
Business Acquisition [Line Items]
contingent consideration liability, projected year of payment	2018
Maximum [Member] | revenue-based payments [Member] | Discounted cash flow [Member]
Business Acquisition [Line Items]
Risk-adjusted discount rate for contingent consideration	18.00%
contingent consideration liability, probability of payment	100.00%
contingent consideration liability, projected year of payment	2018
Minimum [Member] | R&D- and commercialization-based milestones [Member]
Business Acquisition [Line Items]
Risk-adjusted discount rate for contingent consideration	1.00%
contingent consideration liability, probability of payment	45.00%
contingent consideration liability, projected year of payment	2013
Minimum [Member] | revenue-based payments [Member] | Monte Carlo [Member]
Business Acquisition [Line Items]
contingent consideration liability, projected year of payment	2013
Minimum [Member] | revenue-based payments [Member] | Discounted cash flow [Member]
Business Acquisition [Line Items]
Risk-adjusted discount rate for contingent consideration	12.00%
contingent consideration liability, probability of payment	15.00%
contingent consideration liability, projected year of payment	2013