|
Revenue by geographic location (Details) (USD $)
|
3 Months Ended | 6 Months Ended | 3 Months Ended | 6 Months Ended | 3 Months Ended | 6 Months Ended | 3 Months Ended | 6 Months Ended | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Oct. 31, 2012
|
Oct. 31, 2011
|
Oct. 31, 2012
|
Oct. 31, 2011
|
Oct. 31, 2012
United States
|
Oct. 31, 2011
United States
|
Oct. 31, 2012
United States
|
Oct. 31, 2011
United States
|
Oct. 31, 2012
Europe
|
Oct. 30, 2011
Europe
|
Oct. 31, 2012
Europe
|
Oct. 31, 2011
Europe
|
Oct. 31, 2012
Other (principally Asia Pacific Region)
|
Oct. 31, 2011
Other (principally Asia Pacific Region)
|
Oct. 31, 2012
Other (principally Asia Pacific Region)
|
Oct. 31, 2011
Other (principally Asia Pacific Region)
|
|
| Revenues by geographic location | $ 6,959,023 | $ 10,406,008 | $ 14,957,508 | $ 20,675,814 | $ 6,005,147 | $ 8,570,416 | $ 11,980,351 | $ 17,264,993 | $ 628,238 | $ 1,224,412 | $ 1,950,160 | $ 2,423,706 | $ 325,638 | $ 611,180 | $ 1,026,997 | $ 987,115 |