Summary of Significant Accounting Policies (Narrative) (Details) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014 USD ($) country	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2013 CHF
Accounting Policies [Abstract]
Number of countries operated in (over 100 countries)	100
Years in operation	50 years
Common shares, authorized	1,356,000,000			840,000,000
Par value (in dollars or CHF per share)	$ 0.001			1.16
Principles of Consolidation
Maximum exposure to loss associated with variable interest	$ 42
Guaranteed debt on behalf of variable interest entities	70
Foreign Currency
Foreign currency transaction gain (loss)	$ (18)	$ (66)	$ (85)