Description of the Business and Summary of Significant Accounting Policies Description of the Business and Summary of Significant Accounting Policies Out of Period (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended		3 Months Ended
	Dec. 31, 2014	Dec. 31, 2012	Mar. 31, 2012
Revisions and Out-of-Period Items
Out Of Period Adjustment	$ (13)	$ 13
Out of Period Adjustment After Tax	1	15
South Africa [Member]
Revisions and Out-of-Period Items
Out Of Period Adjustment			14
Out of Period Adjustment After Tax			10
Latin America [Member]
Revisions and Out-of-Period Items
Out Of Period Adjustment	$ (15)