Accumulated Other Comprehensive Loss (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Significant amounts reclassified out of each component of AOCI
Earnings before income tax expense	$ 1,239	$ 1,006
Tax expense	(271)	(123)
Net earnings	968	883
Amount reclassified from accumulated other comprehensive loss
Significant amounts reclassified out of each component of AOCI
Net earnings	19
Pension and post-employment benefits | Amount reclassified from accumulated other comprehensive loss
Significant amounts reclassified out of each component of AOCI
Prior-service costs	1
Actuarial losses	27
Earnings before income tax expense	28
Tax expense	$ (9)