Goodwill and Intangible Assets (Details 2) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Changes in intangible assets during the year      
Cost   $ 33,493 $ 24,972
Balance at the beginning of the period, net 21,196 17,769  
Additions 624 8,521  
Amortization Expense (4,825) (5,094) (3,485)
Balance at the end of the period, net 16,995 21,196 17,769
Developed technology
     
Changes in intangible assets during the year      
Cost   20,576 15,179
Balance at the beginning of the period, net 12,384 10,626  
Additions 611 5,397  
Amortization Expense (3,326) (3,639)  
Balance at the end of the period, net 9,669 12,384  
Developed technology | Weighted average
     
Changes in intangible assets during the year      
Amortization period 4 years 3 months 11 days 5 years 1 month 6 days  
Customer relationships
     
Changes in intangible assets during the year      
Cost   8,154 6,884
Balance at the beginning of the period, net 4,952 4,542  
Additions 0 1,270  
Amortization Expense (876) (860)  
Balance at the end of the period, net 4,076 4,952  
Customer relationships | Weighted average
     
Changes in intangible assets during the year      
Amortization period 4 years 10 months 20 days 5 years 9 months 18 days  
Tradenames
     
Changes in intangible assets during the year      
Cost   1,522 1,202
Balance at the beginning of the period, net 1,040 942  
Additions 0 320  
Amortization Expense (212) (222)  
Balance at the end of the period, net 828 1,040  
Tradenames | Weighted average
     
Changes in intangible assets during the year      
Amortization period 5 years 2 months 8 days 5 years 10 months 24 days  
Favorable lease
     
Changes in intangible assets during the year      
Cost   40 40
Balance at the beginning of the period, net 1 14  
Additions 13    
Amortization Expense (14) (13)  
Balance at the end of the period, net 0 1  
Patents and licenses
     
Changes in intangible assets during the year      
Cost   3,059 1,525
Balance at the beginning of the period, net 2,744 1,522  
Additions 0 1,534  
Amortization Expense (351) (312)  
Balance at the end of the period, net 2,393 2,744  
Patents and licenses | Weighted average
     
Changes in intangible assets during the year      
Amortization period 7 years 6 months 29 days 8 years 4 months 24 days  
Other
     
Changes in intangible assets during the year      
Cost   142 142
Balance at the beginning of the period, net 75 123  
Amortization Expense (46) (48)  
Balance at the end of the period, net $ 29 $ 75  
Other | Weighted average
     
Changes in intangible assets during the year      
Amortization period 0 years 6 months 1 year 6 months