Information Relating to the Consolidated Statement of Cash Flows (Details Textual) (USD $) Share data in Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Supplemental Cash Flow Elements [Abstract]
Reduction for income tax benefits associated with stock options exercised	$ 55,000,000	$ 34,000,000
Net purchases of treasury shares	2,500,000,000	2,500,000,000
Stock repurchased during period (in shares)	21.1	23.9
Stock repurchased during period	$ 2,500,000,000	$ 2,500,000,000