Trading and Available-For-Sale Securities at Fair Value (Tables)
   | 
12 Months Ended | 
Mar. 31, 2020  | 
| Debt Securities, Trading, and Equity Securities, FV-NI [Abstract] | 
 
 | 
| Schedule of trading securities | 
    |   | 
      | 
    
         March 31, 
        2020 
 | 
      | 
      | 
    
         March 31, 
        2019 
 | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
      | 
      | 
 
    | Debt securities | 
      | 
    $ | 
    87,014 | 
      | 
      | 
    $ | 
    62,691 | 
      | 
 
    | Equity securities | 
      | 
      | 
    69,530 | 
      | 
      | 
      | 
    105,017 | 
      | 
 
    | Mutual investment funds | 
      | 
      | 
    - | 
      | 
      | 
      | 
    241 | 
      | 
 
    | Total trading securities | 
      | 
    $ | 
    156,544 | 
      | 
      | 
    $ | 
    167,949 | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
 
    | Certificate of deposit | 
      | 
    $ | 
    5,076 | 
      | 
      | 
    $ | 
    - | 
      | 
 
    | Mutual investment funds | 
      | 
      | 
    672 | 
      | 
      | 
      | 
    - | 
      | 
 
    | Debt securities | 
      | 
      | 
    405 | 
      | 
      | 
      | 
    - | 
      | 
 
    | Preferred shares | 
      | 
      | 
    284 | 
      | 
      | 
      | 
    - | 
      | 
 
    | Equity securities | 
      | 
      | 
    1 | 
      | 
      | 
      | 
    2 | 
      | 
 
    | Total available-for-sale securities, at fair value | 
      | 
    $ | 
    6,438 | 
      | 
      | 
    $ | 
    2 | 
      | 
 
 
 | 
| Assets at fair value on a recurring basis | 
    |   | 
      | 
      | 
      | 
      | 
    Fair Value Measurements at | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
    March 31, 2020 using | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
    Quoted Prices in Active Markets for Identical Assets | 
      | 
      | 
    Significant Other Observable Inputs | 
      | 
      | 
    Significant unobservable units | 
      | 
 
    |   | 
      | 
    March 31, 2020 | 
      | 
      | 
    (Level 1) | 
      | 
      | 
    (Level 2) | 
      | 
      | 
    (Level 3) | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
 
    | Debt securities | 
      | 
    $ | 
    87,014 | 
      | 
      | 
    $ | 
    87,014 | 
      | 
      | 
    $ | 
    - | 
      | 
      | 
    $ | 
    - | 
      | 
 
    | Equity securities | 
      | 
      | 
    69,530 | 
      | 
      | 
      | 
    58,271 | 
      | 
      | 
      | 
    - | 
      | 
      | 
      | 
    11,259 | 
      | 
 
    | Total trading securities | 
      | 
    $ | 
    156,544 | 
      | 
      | 
    $ | 
    145,285 | 
      | 
      | 
    $ | 
    - | 
      | 
      | 
    $ | 
    11,259 | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
 
    |  Equity securities | 
      | 
    $ | 
    1 | 
      | 
      | 
    $ | 
    - | 
      | 
      | 
    $ | 
    - | 
      | 
      | 
    $ | 
    1 | 
      | 
 
    |  Debt securities | 
      | 
      | 
    405 | 
      | 
      | 
      | 
    - | 
      | 
      | 
      | 
    405 | 
      | 
      | 
      | 
    - | 
      | 
 
    |  Certificate of deposit | 
      | 
      | 
    5,076 | 
      | 
      | 
      | 
    - | 
      | 
      | 
      | 
    5,076 | 
      | 
      | 
      | 
    - | 
      | 
 
    |  Mutual investment funds | 
      | 
      | 
    672 | 
      | 
      | 
      | 
    672 | 
      | 
      | 
      | 
    - | 
      | 
      | 
      | 
    - | 
      | 
 
    |  Preferred shares | 
      | 
      | 
    284 | 
      | 
      | 
      | 
    - | 
      | 
      | 
      | 
    284 | 
      | 
      | 
      | 
    - | 
      | 
 
    | Total available-for-sale securities, at fair value | 
      | 
    $ | 
    6,438 | 
      | 
      | 
    $ | 
    672 | 
      | 
      | 
    $ | 
    5,765 | 
      | 
      | 
    $ | 
    1 | 
      | 
 
 
  
    |   | 
      | 
      | 
      | 
      | 
    Fair Value Measurements at | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
    March 31, 2019 using | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
    Quoted Prices in Active Markets for Identical Assets | 
      | 
      | 
    Significant Other Observable Inputs | 
      | 
      | 
    Significant unobservable units | 
      | 
 
    |   | 
      | 
    March 31, 2019 | 
      | 
      | 
    (Level 1) | 
      | 
      | 
    (Level 2) | 
      | 
      | 
    (Level 3) | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
 
    | Equity securities | 
      | 
    $ | 
    105,017 | 
      | 
      | 
    $ | 
    105,017 | 
      | 
      | 
    $ | 
    - | 
      | 
      | 
    $ | 
    - | 
      | 
 
    | Debt securities | 
      | 
      | 
    62,691 | 
      | 
      | 
      | 
    62,187 | 
      | 
      | 
      | 
    - | 
      | 
      | 
      | 
    504 | 
      | 
 
    | Mutual investment funds | 
      | 
      | 
    241 | 
      | 
      | 
      | 
    241 | 
      | 
      | 
      | 
    - | 
      | 
      | 
      | 
    - | 
      | 
 
    | Total trading securities | 
      | 
    $ | 
    167,949 | 
      | 
      | 
    $ | 
    167,445 | 
      | 
      | 
    $ | 
    - | 
      | 
      | 
    $ | 
    504 | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
 
    | Equity securities | 
      | 
    $ | 
    2 | 
      | 
      | 
    $ | 
    - | 
      | 
      | 
    $ | 
    - | 
      | 
      | 
    $ | 
    2 | 
      | 
 
    | Total available-for-sale securities, at fair value | 
      | 
    $ | 
    2 | 
      | 
      | 
    $ | 
    - | 
      | 
      | 
    $ | 
    - | 
      | 
      | 
    $ | 
    2 | 
      | 
 
 
 | 
| Level 3 inputs and valuation techniques | 
    | Type | 
    Valuation Technique | 
    FV as of March 31, 2020 | 
    FV as of March 31, 2019 | 
    Significant Unobservable Inputs | 
    % | 
 
    |   | 
      | 
      | 
      | 
      | 
      | 
 
    | Corporate bonds | 
    DCF | 
    - | 
    $ 504 | 
    Discount rate | 
    11.3% | 
 
    | Equity securities | 
    DCF | 
    $11,259 | 
    - | 
    Discount rate | 
    9.5% | 
 
    |   | 
      | 
      | 
      | 
    Estimated number of years | 
    9 years | 
 
 
 | 
| Reconciliation of beginning and ending balances for investments using level 3 inputs | 
    |   | 
      | 
    Trading securities | 
      | 
      | 
    Available-for-sale securities | 
      | 
 
    | Balance as of March 31, 2019 | 
      | 
    $ | 
    504 | 
      | 
      | 
    $ | 
    2 | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
 
    | Sale of investments that use Level 3 inputs | 
      | 
      | 
    (497 | 
    ) | 
      | 
      | 
    - | 
      | 
 
    | Purchase of investments that use Level 3 inputs | 
      | 
      | 
    10,430 | 
      | 
      | 
      | 
    - | 
      | 
 
    | Revaluation of investments that use Level 3 inputs | 
      | 
      | 
    829 | 
      | 
      | 
      | 
    - | 
      | 
 
    | Foreign currency translation | 
      | 
      | 
    (7 | 
    ) | 
      | 
      | 
    - | 
      | 
 
    | Balance as of March 31, 2020 | 
      | 
    $ | 
    11,259 | 
      | 
      | 
    $ | 
    2 | 
      | 
 
 
 | 
| Available for sale securities | 
    |   | 
      | 
      | 
      | 
      | 
    March 31, 2020 | 
      | 
      | 
      | 
      | 
 
    |   | 
      | 
    Assets measured at amortized cost | 
      | 
      | 
    Unrealized loss accumulated in other comprehensive income/(loss) | 
      | 
      | 
    Assets measured at fair value | 
      | 
 
    |   | 
      | 
      | 
      | 
 
    | Certificate of deposit | 
      | 
    $ | 
    5,050 | 
      | 
      | 
    $ | 
    26 | 
      | 
      | 
    $ | 
    5,076 | 
      | 
 
    | Mutual investment funds | 
      | 
      | 
    696 | 
      | 
      | 
      | 
    (24 | 
    ) | 
      | 
      | 
    672 | 
      | 
 
    | Debt securities | 
      | 
      | 
    456 | 
      | 
      | 
      | 
    (51 | 
    ) | 
      | 
      | 
    405 | 
      | 
 
    | Preferred shares | 
      | 
      | 
    306 | 
      | 
      | 
      | 
    (22 | 
    ) | 
      | 
      | 
    284 | 
      | 
 
    | Equity securities | 
      | 
      | 
    1 | 
      | 
      | 
      | 
    - | 
      | 
      | 
      | 
    1 | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
 
    | Balance as of March 31, 2020 | 
      | 
    $ | 
    6,509 | 
      | 
      | 
    $ | 
    (71) | 
     | 
      | 
    $ | 
    6,438 | 
      | 
 
 
  
    |   | 
      | 
      | 
      | 
      | 
    March 31, 2019 | 
      | 
      | 
      | 
      | 
 
    |   | 
      | 
    Assets measured at amortized cost | 
      | 
      | 
    Unrealized loss accumulated in other comprehensive income/(loss) | 
      | 
      | 
    Assets measured at fair value | 
      | 
 
    |   | 
      | 
      | 
      | 
 
    | Equity securities | 
      | 
    $ | 
    1 | 
      | 
      | 
    $ | 
    1 | 
      | 
      | 
    $ | 
    2 | 
      | 
 
    |   | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
      | 
 
    | Balance as of March 31, 2019 | 
      | 
    $ | 
    1 | 
      | 
      | 
    $ | 
    1 | 
      | 
      | 
    $ | 
    2 | 
      | 
 
 
  
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