Derivative Financial Instruments (Summary of aggregate contractual or notional amounts and gross estimated fair values related to derivative financial instruments) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Derivative [Line Items]
Contractual/notional amount	$ 11	$ 5
Estimated fair value asset
Estimated fair value (liability)
Not Designated as Hedging Instrument [Member] | Foreign Exchange Forward [Member]
Derivative [Line Items]
Contractual/notional amount	6
Estimated fair value asset
Estimated fair value (liability)
Not Designated as Hedging Instrument [Member] | Warrant [Member]
Derivative [Line Items]
Contractual/notional amount	5	5
Estimated fair value asset
Estimated fair value (liability)