Benefit Obligations (Pension and Other Postretirement Obligations Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended				3 Months Ended	12 Months Ended			3 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 UNITED STATES	Dec. 31, 2013 Pension Benefits [Member]	Dec. 31, 2013 Pension Benefits [Member]	Dec. 31, 2012 Pension Benefits [Member]	Dec. 31, 2011 Pension Benefits [Member]	Dec. 31, 2013 Pension Benefits [Member] UNITED KINGDOM	Dec. 31, 2013 Postretirement Benefits [Member]	Dec. 31, 2012 Postretirement Benefits [Member]	Dec. 31, 2011 Postretirement Benefits [Member]	Nov. 05, 2013 Postretirement Benefits [Member] UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Settlement loss						$ 9	$ 0	$ 0	$ 9	$ 0	$ 0	$ 0
Curtailment (gain)					(61)	(61)	0	0		0	0	0
Multiemployer plans, funded status	At least 80 percent	At least 80 percent	At least 80 percent
Multiemployer plans, period contributions, significance of contributions	false	false
Prior service cost credit													92
Lump-sum buyout payments				$ 23		$ 173	$ 0			$ 23	$ 0