Description of Business and Summary of Significant Accounting Policies (Details 4) (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Product Warranty  
Product warranty period 2 years
Changes in the product warranty liability  
Balance at beginning of period $ 1,191
Warranty costs accrued 750
Warranty claims (612)
Balance at end of period $ 1,329