Commitments and Contingencies (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Summary of liability related to lease
Beginning Balance	$ 452	$ 567
Net rental receipts (payments)	(19)	20
Accretion of discount	18	22
Increase in estimated contract termination costs	39
Ending Balance	$ 490	$ 609