Commitments and Contingencies Commitments and Contingencies Disclosure (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Commitments and Contingencies Disclosure [Abstract]
Litigation Settlement, Expense	$ 3

This element represents the expenses incurred by the entity which are directly related and attributable to receiving an award in settlement of litigation.

No definition available.

Name:	us-gaap_LitigationSettlementExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration