Quarterly Financial Information (Detail) - USD ($) |
3 Months Ended | 12 Months Ended | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Nov. 30, 2018 |
Aug. 31, 2018 |
May 31, 2018 |
Feb. 28, 2018 |
Nov. 30, 2017 |
Aug. 31, 2017 |
May 31, 2017 |
Feb. 28, 2017 |
Nov. 30, 2016 |
Aug. 31, 2016 |
May 31, 2016 |
Feb. 28, 2016 |
May 31, 2018 |
May 31, 2017 |
May 31, 2016 |
|
| Operating expenses | $ (10,775,051) | $ (9,807,001) | $ (11,196,754) | $ (14,140,507) | $ (6,156,117) | $ (5,358,120) | $ (7,799,580) | $ (8,016,917) | $ (2,893,779) | $ (6,657,481) | $ (6,575,214) | $ (5,049,037) | $ (45,919,313) | $ (27,330,734) | $ (21,175,511) |
| Other income (expense) | 830,022 | (361,879) | 1,966,816 | (740,404) | 1,229,114 | 3,735 | 969,929 | (23,078) | 211 | 62,686 | 78,045 | 2,202 | |||
| Interest expense | (1,002,656) | (1,459,393) | (393,685) | (3,069,189) | (540,330) | (72,437) | (2,371,025) | (2,300,220) | (5,924,923) | (612,767) | (4,671,245) | ||||
| Net (loss) | $ (10,947,685) | $ (11,628,273) | $ (9,623,623) | $ (17,950,100) | $ (5,467,333) | $ (5,354,385) | $ (6,829,651) | $ (8,112,432) | $ (5,264,593) | $ (8,895,015) | $ (6,497,169) | $ (5,046,835) | $ (50,149,681) | $ (25,763,801) | $ (25,703,612) |
| Basic and diluted loss per share | $ (0.07) | $ (0.08) | $ (0.04) | $ (0.10) | $ (0.04) | $ (0.04) | $ (0.05) | $ (0.06) | $ (0.06) | $ (0.12) | $ (0.04) | $ (0.05) | |||
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- Definition The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of the cost of borrowed funds accounted for as interest expense. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense. No definition available.
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- Definition Amount of income (expense) related to nonoperating activities, classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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