Balance Sheet Components (Details) (USD $)
In Thousands, unless otherwise specified
Jun. 30, 2014
Dec. 31, 2013
Inventories    
Finished goods $ 14,985 $ 14,061
Component parts 1,005 1,251
Total inventories 15,990 15,312
Property and equipment, net    
Property and equipment, gross 13,939 13,278
Less: accumulated depreciation (9,998) (9,335)
Property and equipment, net 3,941 3,943
Computer equipment and software
   
Property and equipment, net    
Property and equipment, gross 4,082 4,152
Manufacturing tooling and test equipment
   
Property and equipment, net    
Property and equipment, gross 2,682 2,652
Lab and warehouse equipment
   
Property and equipment, net    
Property and equipment, gross 2,563 2,374
Furniture and fixtures
   
Property and equipment, net    
Property and equipment, gross 2,386 2,046
Leasehold improvements
   
Property and equipment, net    
Property and equipment, gross 1,572 1,450
Marketing equipment
   
Property and equipment, net    
Property and equipment, gross $ 654 $ 604