Related Party Transactions (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2012	Jun. 30, 2013	Dec. 31, 2012
Notional Amount of Derivatives [Line Items]
Notional amount of foreign currency derivatives			$ 26	$ 355
Unrealized gain (loss) on derivatives in other income (expense)	(1)	(1)
Realized gain (loss) on derivatives in other income (expense)	$ 3	$ 2

Aggregate notional amount of foreign currency exchange rate derivatives. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

Name:	us-gaap_NotionalAmountOfForeignCurrencyDerivatives
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant