Other Financial Data (Investments) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Investments
Short-term Investments	$ 2	$ 2
Investments	251	240
Unrealized Gains	0	3
Cost Basis	253	239
Available-For-Sale Securities [Member]
Investments
Short-term Investments	2	2
Investments	35	38
Unrealized Gains	0	3
Cost Basis	37	37
Government, agency, and government-sponsored enterprise obligations
Investments
Short-term Investments	0	0
Investments	15	15
Unrealized Gains	0	0
Cost Basis	15	15
Corporate bonds
Investments
Short-term Investments	2	2
Investments	7	11
Unrealized Gains	0	0
Cost Basis	9	13
Mortgage-backed securities
Investments
Short-term Investments		0
Investments		2
Unrealized Gains		0
Cost Basis		2
Mutual funds
Investments
Short-term Investments	0
Investments	11
Unrealized Gains	0
Cost Basis	11
Common stock and equivalents
Investments
Short-term Investments	0	0
Investments	2	10
Unrealized Gains	0	3
Cost Basis	2	7
Other Securities, At Cost
Investments
Short-term Investments	0	0
Investments	201	189
Unrealized Gains	0	0
Cost Basis	201	189
Equity Method Investments
Investments
Short-term Investments	0	0
Investments	15	13
Unrealized Gains	0	0
Cost Basis	$ 15	$ 13