Industry Segments and Financial Information About Foreign and Domestic Operations (Schedule of Segment Reporting Information) (Details) - USD ($) |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2015 |
Sep. 30, 2017 |
Sep. 30, 2016 |
Sep. 30, 2015 |
|
| Operating (loss) income | $ (8,494,112) | $ 3,018,512 | $ 6,618,407 | ||||||||
| Revenues | $ 3,692,406 | $ 4,314,068 | $ 2,405,519 | $ 3,243,599 | $ 3,563,106 | $ 5,560,776 | $ 4,772,801 | $ 8,230,659 | 13,655,592 | 22,127,342 | 32,604,865 |
| R&D [Member] | Operating Segments [Member] | |||||||||||
| Operating (loss) income | (3,244,000) | (89,000) | (220,000) | ||||||||
| Corporate [Member] | |||||||||||
| Operating (loss) income | (8,394,000) | (6,824,000) | (6,607,000) | ||||||||
| Zimbabwe [Member] | |||||||||||
| Revenues | 2,227,000 | 3,305,000 | 2,696,000 | ||||||||
| Mozambique [Member] | |||||||||||
| Revenues | 1,430,000 | ||||||||||
| U.S. [Member] | |||||||||||
| Revenues | 1,288,000 | 2,464,000 | 2,029,000 | ||||||||
| U.S. [Member] | Operating Segments [Member] | |||||||||||
| Operating (loss) income | 3,144,000 | 9,932,000 | 13,445,000 | ||||||||
| South Africa [Member] | |||||||||||
| Revenues | 951,000 | 1,117,000 | 2,331,000 | ||||||||
| Cameroon [Member] | |||||||||||
| Revenues | 891,000 | ||||||||||
| Nigeria [Member] | |||||||||||
| Revenues | 846,000 | ||||||||||
| Brazil [Member] | |||||||||||
| Revenues | 6,008,000 | 14,841,000 | |||||||||
| Other [Member] | |||||||||||
| Revenues | $ 6,022,000 | $ 9,233,000 | $ 10,708,000 | ||||||||