Note 4 - Gross Unrealized Losses and Fair Value of Investments (Details) - USD ($)
|
12 Months Ended |
Mar. 31, 2016 |
Mar. 31, 2015 |
| Corporate Bond Securities [Member] |
|
|
| Fair market value, less than 12 months |
$ 3,003,606
|
$ 3,015,900
|
| Gross unrealized losses, less than 12 months |
(6,703)
|
(163)
|
| Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |
2,599,870
|
2,590,240
|
| Gross unrealized losses, greater than 12 months |
(4,121)
|
(16,208)
|
| Total Fair Market Value |
5,603,476
|
5,606,140
|
| Total Gross Unrealized Losses |
$ (10,824)
|
$ (16,371)
|
| Municipal Bonds [Member] |
|
|
| Fair market value, less than 12 months |
|
|
| Gross unrealized losses, less than 12 months |
|
|
| Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |
|
|
| Gross unrealized losses, greater than 12 months |
|
|
| Total Fair Market Value |
|
|
| Total Gross Unrealized Losses |
|
|
| Fair market value, less than 12 months |
$ 3,003,606
|
$ 3,015,900
|
| Gross unrealized losses, less than 12 months |
(6,703)
|
(163)
|
| Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |
2,599,870
|
2,590,240
|
| Gross unrealized losses, greater than 12 months |
(4,121)
|
(16,208)
|
| Total Fair Market Value |
5,603,476
|
5,606,140
|
| Total Gross Unrealized Losses |
$ (10,824)
|
$ (16,371)
|