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v3.20.4

Other income (Tables) | 12 Months Ended
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Dec. 31, 2020
Component of Operating Income [Abstract] |
Schedule of other income | Other income consisted of the following for the years ended December 31, 2020, 2019 and 2018:
| Year Ended December 31,
| 2020 |  | 2019 | 2018
Management fees | $ | 9,701 |  |  |  | $ | 12,445 |  |  | $ | 14,539 |
Interest and other income | 73,304 |  |  |  | 53,794 |  |  | 47,025 |
| $ | 83,005 |  |  |  | $ | 66,239 |  |  | $ | 61,564 |

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- Definition Tabular disclosure of interest income and income classified as other. + References No definition available. + Details
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