Income Taxes Effective Rate Reconciliation (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Effective Rate Reconciliation [Abstract]
Income Tax Reconciliation, Income Tax Benefit, at Federal Statutory Income Tax Rate									$ (5,390)	$ (5,050)	$ (4,537)
Income Tax Reconciliation, State and Local Income Taxes									(577)	17	5
U.S.-Foreign rate differential									100	342	87
Change in Valuation Allowance									4,115	5,862	4,530
Income Tax Reconciliation, Tax Credits, Research									357	(1,241)	0
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Amount									1,560	406	0
Others									46	(25)	134
Total income tax expense	$ 97	$ 33	$ 106	$ (25)	$ 55	$ 113	$ 106	$ 37	$ 211	$ 311	$ 219