| 
           9. Segment and Geographic Information (Details) (USD $) 
        In Thousands, unless otherwise specified  | 
        3 Months Ended | |
|---|---|---|
| 
           Jun. 30, 2012 
         | 
        
           Jun. 30, 2011 
         | 
      |
| Revenues from External Customers and Long-Lived Assets [Line Items] | ||
| Sales revenue from Geographical territories | $ 3,816 | $ 2,710 | 
| 
           UnitedStatesOfAmericaMember 
         | 
        ||
| Revenues from External Customers and Long-Lived Assets [Line Items] | ||
| Sales revenue from Geographical territories | 2,033 | 840 | 
| 
           MexicoMember 
         | 
        ||
| Revenues from External Customers and Long-Lived Assets [Line Items] | ||
| Sales revenue from Geographical territories | 1,378 | 1,380 | 
| 
           SegmentGeographicalGroupsOfCountriesGroupOneMember 
         | 
        ||
| Revenues from External Customers and Long-Lived Assets [Line Items] | ||
| Sales revenue from Geographical territories | $ 405 | $ 490 |