Derivative Financial Instruments (Schedule of Offsetting Liabilities) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Derivative Liability [Abstract]
Gross amount recognized	$ 16	$ 32
Gross amount offset in the consolidated balance sheets	1	1
Net amount presented in the consolidated balance sheets	15	31
Gross amount not offset in the consolidated balance sheets	1	2
Net amount	$ 14	$ 29