Summary of Significant Accounting Policies Narrative (Details) (USD $)
12 Months Ended 0 Months Ended 12 Months Ended
Dec. 31, 2013
segment
Dec. 31, 2012
segment
Dec. 31, 2011
Dec. 31, 2013
Maximum [Member]
Dec. 31, 2012
Equipment [Member]
Minimum [Member]
Dec. 31, 2012
Equipment [Member]
Maximum [Member]
Nov. 23, 2011
IPO [Member]
Nov. 23, 2011
Stockholder [Member]
IPO [Member]
Dec. 31, 2012
Patents [Member]
Maximum [Member]
Accounting Policies [Abstract]                  
Accumulated deficit $ (110,124,000) $ (101,305,000)              
Shares of common stock sold and issued             5,681,796 3,968,204  
Sale of Stock, Price Per Share             $ 10.00    
Proceeds From Issuance Initial Public Offering, Gross             56,800,000    
Proceeds from initial public offering, net of expenses 0 0 49,217,000       49,200,000    
Payments of Underwriting Discounts and Commissions             4,000,000    
Payments of Other Offering Costs             3,600,000    
Inventory, Net [Abstract]                  
Inventory raw materials noncurrent 6,500,000 2,400,000              
Inventory work in process noncurrent 0 800,000              
Inventory Write-down 1,000,000                
Property, Plant and Equipment, Useful Life         3 years 5 years      
Finite-Lived Intangible Asset, Useful Life       20 years         20 years
Impairment of Long-Lived Assets                  
Asset impairment charges $ 0 $ 949,000 $ 0            
Number of Reportable Segments 1 1