Commitments and Contingencies (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Loss Contingencies [Line Items]
Litigation Settlement, Expense	$ 0	$ 0	$ 2,950

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