7. STOCK- BASED COMPENSATION (Details) (USD $) | 3 Months Ended | 9 Months Ended |
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2013 | Dec. 31, 2012 |
Shares available for grant | ' | ' | ' | ' |
Shares of common stock available for grant, Ending | 5,671,955 | ' | 5,671,955 | ' |
Number of Options | ' | ' | ' | ' |
Number of Underlying Options Outstanding, Beginning | ' | ' | 6,336,319 | ' |
Number of Underlying Options Granted | ' | ' | 678,483 | ' |
Number of Underlying Options Exercised | ' | ' | -723,673 | ' |
Number of Underlying Options Forfeited | ' | ' | -141,320 | ' |
Number of Options Underlying Outstanding, Ending | 6,149,809 | ' | 6,149,809 | ' |
Options Vested and Exercisable | 3,748,121 | ' | 3,748,121 | ' |
Options Vested and expected to vest | 6,083,320 | ' | 6,083,320 | ' |
Weighted Average Exercise Price | ' | ' | ' | ' |
Weighted Average Exercise Price Outstanding, Beginning | ' | ' | $4.73 | ' |
Weighted Average Exercise Price Granted | ' | ' | $6.42 | ' |
Weighted Average Exercise Price Exercised | ' | ' | $2.97 | ' |
Weighted Average Exercise Price Forfeited | ' | ' | $6.01 | ' |
Weighted Average Exercise Price Outstanding, Ending | $5.09 | ' | $5.09 | ' |
Weighted Average Exercise Price Vested and Exercisable | $4.56 | ' | $4.56 | ' |
Weighted Average Exercise Price vested and expected to vest | $5.08 | ' | $5.08 | ' |
Weighted Average Remaining Contractual Life (in years) | ' | ' | ' | ' |
Weighted Average Remaining Contractual Life (in years) Exercisable | ' | ' | '4 years 9 months 11 days | ' |
Weighted Average Remaining Contractual Life (in years) Vested and expected to vest | ' | ' | '6 years 1 month 13 days | ' |
Aggregate Intrinsic Value | ' | ' | ' | ' |
Intrinsic Value of Exercised Options | ' | ' | $2,386,568 | ' |
Aggregate Intrinsic Value Exercisable | 7,989,938 | ' | 7,989,938 | ' |
Aggregate Intrinsic Value vested and expected to vest | $9,916,505 | ' | $9,916,505 | ' |
Weighted average fair value per underlying share of options granted (in dollars per share) | $2.78 | $2.43 | $2.73 | $2.12 |
Options outstanding by exercise price | ' | ' | ' | ' |
Exercise Price (in dollars per share) | $5.09 | ' | $5.09 | ' |
Number of Shares Underlying Options Outstanding (in shares) | 6,149,809 | ' | 6,149,809 | ' |
Options Exercisable, Number Vested and Exercisable (in shares) | 3,748,121 | ' | 3,748,121 | ' |
$2.43 - 3.38 | ' | ' | ' | ' |
Options outstanding by exercise price | ' | ' | ' | ' |
Exercise Price, low end of range (in dollars per share) | ' | ' | $2.43 | ' |
Exercise Price, high end of range (in dollars per share) | ' | ' | $3.38 | ' |
Number of Shares Underlying Options Outstanding (in shares) | 647,144 | ' | 647,144 | ' |
Options Outstanding, Weighted Average Exercise Price (in dollars per share) | $3.01 | ' | $3.01 | ' |
Options Outstanding, Weighted Average Remaining Contractual Life (Years) | ' | ' | '4 years 9 months 11 days | ' |
Options Exercisable, Number Vested and Exercisable (in shares) | 647,144 | ' | 647,144 | ' |
Options Exercisable, Weighted Average Exercise Price (in dollars per share) | $3.01 | ' | $3.01 | ' |
$3.43 - 3.94 | ' | ' | ' | ' |
Options outstanding by exercise price | ' | ' | ' | ' |
Exercise Price, low end of range (in dollars per share) | ' | ' | $3.43 | ' |
Exercise Price, high end of range (in dollars per share) | ' | ' | $3.94 | ' |
Number of Shares Underlying Options Outstanding (in shares) | 498,291 | ' | 498,291 | ' |
Options Outstanding, Weighted Average Exercise Price (in dollars per share) | $3.55 | ' | $3.55 | ' |
Options Outstanding, Weighted Average Remaining Contractual Life (Years) | ' | ' | '5 years 3 months 7 days | ' |
Options Exercisable, Number Vested and Exercisable (in shares) | 498,291 | ' | 498,291 | ' |
Options Exercisable, Weighted Average Exercise Price (in dollars per share) | $3.55 | ' | $3.55 | ' |
$4 | ' | ' | ' | ' |
Weighted Average Exercise Price | ' | ' | ' | ' |
Weighted Average Exercise Price Outstanding, Ending | $4 | ' | $4 | ' |
Options outstanding by exercise price | ' | ' | ' | ' |
Exercise Price (in dollars per share) | $4 | ' | $4 | ' |
Number of Shares Underlying Options Outstanding (in shares) | 697,038 | ' | 697,038 | ' |
Options Outstanding, Weighted Average Exercise Price (in dollars per share) | $4 | ' | $4 | ' |
Options Outstanding, Weighted Average Remaining Contractual Life (Years) | ' | ' | '5 years 5 months 5 days | ' |
Options Exercisable, Number Vested and Exercisable (in shares) | 697,038 | ' | 697,038 | ' |
Options Exercisable, Weighted Average Exercise Price (in dollars per share) | $4 | ' | $4 | ' |
$4.17 - 4.50 | ' | ' | ' | ' |
Options outstanding by exercise price | ' | ' | ' | ' |
Exercise Price, low end of range (in dollars per share) | ' | ' | $4.17 | ' |
Exercise Price, high end of range (in dollars per share) | ' | ' | $4.50 | ' |
Number of Shares Underlying Options Outstanding (in shares) | 652,634 | ' | 652,634 | ' |
Options Outstanding, Weighted Average Exercise Price (in dollars per share) | $4.26 | ' | $4.26 | ' |
Options Outstanding, Weighted Average Remaining Contractual Life (Years) | ' | ' | '5 years 10 months 2 days | ' |
Options Exercisable, Number Vested and Exercisable (in shares) | 369,545 | ' | 369,545 | ' |
Options Exercisable, Weighted Average Exercise Price (in dollars per share) | $4.32 | ' | $4.32 | ' |
$4.81 - 4.92 | ' | ' | ' | ' |
Options outstanding by exercise price | ' | ' | ' | ' |
Exercise Price, low end of range (in dollars per share) | ' | ' | $4.81 | ' |
Exercise Price, high end of range (in dollars per share) | ' | ' | $4.92 | ' |
Number of Shares Underlying Options Outstanding (in shares) | 511,335 | ' | 511,335 | ' |
Options Outstanding, Weighted Average Exercise Price (in dollars per share) | $4.87 | ' | $4.87 | ' |
Options Outstanding, Weighted Average Remaining Contractual Life (Years) | ' | ' | '8 years 2 months 8 days | ' |
Options Exercisable, Number Vested and Exercisable (in shares) | 132,690 | ' | 132,690 | ' |
Options Exercisable, Weighted Average Exercise Price (in dollars per share) | $4.88 | ' | $4.88 | ' |
$5.50 | ' | ' | ' | ' |
Weighted Average Exercise Price | ' | ' | ' | ' |
Weighted Average Exercise Price Outstanding, Ending | $5.50 | ' | $5.50 | ' |
Options outstanding by exercise price | ' | ' | ' | ' |
Exercise Price (in dollars per share) | $5.50 | ' | $5.50 | ' |
Number of Shares Underlying Options Outstanding (in shares) | 817,333 | ' | 817,333 | ' |
Options Outstanding, Weighted Average Exercise Price (in dollars per share) | $5.50 | ' | $5.50 | ' |
Options Outstanding, Weighted Average Remaining Contractual Life (Years) | ' | ' | '2 years 10 months 10 days | ' |
Options Exercisable, Number Vested and Exercisable (in shares) | 817,333 | ' | 817,333 | ' |
Options Exercisable, Weighted Average Exercise Price (in dollars per share) | $5.50 | ' | $5.50 | ' |
$5.59 - 5.76 | ' | ' | ' | ' |
Options outstanding by exercise price | ' | ' | ' | ' |
Exercise Price, low end of range (in dollars per share) | ' | ' | $5.59 | ' |
Exercise Price, high end of range (in dollars per share) | ' | ' | $5.76 | ' |
Number of Shares Underlying Options Outstanding (in shares) | 622,280 | ' | 622,280 | ' |
Options Outstanding, Weighted Average Exercise Price (in dollars per share) | $5.70 | ' | $5.70 | ' |
Options Outstanding, Weighted Average Remaining Contractual Life (Years) | ' | ' | '7 years 6 months 18 days | ' |
Options Exercisable, Number Vested and Exercisable (in shares) | 206,845 | ' | 206,845 | ' |
Options Exercisable, Weighted Average Exercise Price (in dollars per share) | $5.71 | ' | $5.71 | ' |
$6.00 - 6.54 | ' | ' | ' | ' |
Options outstanding by exercise price | ' | ' | ' | ' |
Exercise Price, low end of range (in dollars per share) | ' | ' | $6 | ' |
Exercise Price, high end of range (in dollars per share) | ' | ' | $6.54 | ' |
Number of Shares Underlying Options Outstanding (in shares) | 818,658 | ' | 818,658 | ' |
Options Outstanding, Weighted Average Exercise Price (in dollars per share) | $6.32 | ' | $6.32 | ' |
Options Outstanding, Weighted Average Remaining Contractual Life (Years) | ' | ' | '7 years 4 months 17 days | ' |
Options Exercisable, Number Vested and Exercisable (in shares) | 158,299 | ' | 158,299 | ' |
Options Exercisable, Weighted Average Exercise Price (in dollars per share) | $6.34 | ' | $6.34 | ' |
$6.63 - 7.00 | ' | ' | ' | ' |
Options outstanding by exercise price | ' | ' | ' | ' |
Exercise Price, low end of range (in dollars per share) | ' | ' | $6.63 | ' |
Exercise Price, high end of range (in dollars per share) | ' | ' | $7 | ' |
Number of Shares Underlying Options Outstanding (in shares) | 771,476 | ' | 771,476 | ' |
Options Outstanding, Weighted Average Exercise Price (in dollars per share) | $6.86 | ' | $6.86 | ' |
Options Outstanding, Weighted Average Remaining Contractual Life (Years) | ' | ' | '8 years 3 months 29 days | ' |
Options Exercisable, Number Vested and Exercisable (in shares) | 158,221 | ' | 158,221 | ' |
Options Exercisable, Weighted Average Exercise Price (in dollars per share) | $6.93 | ' | $6.93 | ' |
$9.20 | ' | ' | ' | ' |
Weighted Average Exercise Price | ' | ' | ' | ' |
Weighted Average Exercise Price Outstanding, Ending | $9.20 | ' | $9.20 | ' |
Options outstanding by exercise price | ' | ' | ' | ' |
Exercise Price (in dollars per share) | $9.20 | ' | $9.20 | ' |
Number of Shares Underlying Options Outstanding (in shares) | 113,620 | ' | 113,620 | ' |
Options Outstanding, Weighted Average Exercise Price (in dollars per share) | $9.20 | ' | $9.20 | ' |
Options Outstanding, Weighted Average Remaining Contractual Life (Years) | ' | ' | '7 years 29 days | ' |
Options Exercisable, Number Vested and Exercisable (in shares) | 62,715 | ' | 62,715 | ' |
Options Exercisable, Weighted Average Exercise Price (in dollars per share) | $9.20 | ' | $9.20 | ' |