Pension and Other Postretirement Employee Benefit Plans - Pretax Amortization from AOCI (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
Defined Benefit Pension Plans, U.S. [Member]
Estimated pretax amounts that will be amortized from AOCI into net periodic benefit cost
Net loss	$ 276
Prior service cost/(credit)	(41)
Total	235
Defined Benefit Pension Plans, Non-U.S. [Member]
Estimated pretax amounts that will be amortized from AOCI into net periodic benefit cost
Net loss	50
Prior service cost/(credit)	(2)
Total	48
OPEB plans, U.S. [Member]
Estimated pretax amounts that will be amortized from AOCI into net periodic benefit cost
Net loss	5
Prior service cost/(credit)	0
Total	5
OPEB plans, Non-U.S. [Member]
Estimated pretax amounts that will be amortized from AOCI into net periodic benefit cost
Net loss	(1)
Prior service cost/(credit)	0
Total	$ (1)