Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Other Comprehensive Income:
Tax on foreign currency translation	$ 0	$ 0	$ 0	$ 0
Tax on reclassification adjustment for amounts recognized in income	0	0	0	0
Defined benefit plans:
Tax on amortization of prior service cost and unrecognized gains and losses included in total benefit cost	1	2	8	6
Tax on decrease (increase) in net actuarial losses	0	0	2	7
Tax on immediate recognition of prior service cost and unrecognized gains and losses due to curtailments, settlements and divestitures	0	0	0	0
Tax on prior service credit from plan amendments	0	5	0	3
Tax on deferred derivative gains (losses)	0	0	1	0
Tax on reclassification adjustment for amounts recognized in income	0	(1)	1	(3)
Tax on unrealized investment gains (losses)	$ 0	$ 0	$ 0	$ 0