Pension and Other Employee Benefits (Schedule of Components of Net Periodic Benefit Expense (Income) Other Benefits) (Details) (Other Benefits [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Other Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Service cost	$ 8	$ 8	$ 9
Interest cost	32	38	41
Expected return on plan assets	(32)	(31)	(34)
Amounts reflected in net funded status	8	15	16
Amortization of transition obligation	0	1	4
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	(2)	(3)	(10)
Recognized net actuarial loss	4	3	3
Amounts reclassified during the year	2	1	(3)
Net periodic cost (credit)	$ 10	$ 16	$ 13