Income Taxes Components of income tax expense/ (benefit) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Components of Income Tax Expense/ (Benefit) [Abstract]
Current	$ 0	$ 0	$ 0
Deferred	0	0	0
Total federal provision	0	0	0
Current	5	4	4
Deferred	0	0	0
Total state provision	5	4	4
Current	214	325	297
Deferred	0	0	0
Total foreign provision	214	325	297
Total income tax expense (benefit)	$ 219	$ 329	$ 301