v3.20.1

Long-term Investments - Available-for-sale Investment - Additional Information (Details) |  |  | 9 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Apr. 28, 2016 USD ($) | Mar. 30, 2016 USD ($) | Dec. 31, 2017 CNY (¥) | Dec. 31, 2017 USD ($) | Mar. 31, 2017 CNY (¥) | Dec. 31, 2019 CNY (¥) | Dec. 31, 2018 CNY (¥) | Mar. 31, 2017 USD ($) | Mar. 24, 2016 USD ($)
Available-for-sale investment |  |  |  |  |  |  |  |  |
Interest income | ¥ |  |  |  |  | ¥ 568,320 |  |  |  |
Unrealized holding loss of available-for-sale investment reported in other comprehensive income (loss) | ¥ |  |  |  |  | 553,870 |  |  |  |
Net book value | ¥ |  |  |  |  |  | ¥ 0 | ¥ 0 |  |
Convertible promissory note ("the Notes") |  |  |  |  |  |  |  |  |
Available-for-sale investment |  |  |  |  |  |  |  |  |
Aggregate fair value |  |  |  |  | ¥ 10,376,547 |  |  | $ 1,504,000 |
Impairment loss of convertible bond |  |  | ¥ 10,458,538 | $ 1,504,000 |  |  |  |  |
Available-for-sale investment | Brilent Inc. ("Brilent") | Convertible promissory note ("the Notes") |  |  |  |  |  |  |  |  |
Available-for-sale investment |  |  |  |  |  |  |  |  |
Maximum amount of investments allowed for purchase | $ |  |  |  |  |  |  |  |  | $ 2,500,000
ATA BVI | Available-for-sale investment | Brilent Inc. ("Brilent") | Convertible promissory note ("the Notes") |  |  |  |  |  |  |  |  |
Available-for-sale investment |  |  |  |  |  |  |  |  |
Principal amount of investments | $ | $ 1,200,000 | $ 300,000 |  |  |  |  |  |  |
Interest rate per annum (as a percent) | 6.00% | 6.00% |  |  |  |  |  |  |
Cash consideration | $ | $ 1,500,000 |  |  |  |  |  |  |  |
Term of investments | 24 months | 24 months |  |  |  |  |  |  |
Amount converted to, as a percentage of qualified financing security purchase price | 75.00% | 75.00% |  |  |  |  |  |  |

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