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v3.19.3.a.u2

Other income (Tables) | 12 Months Ended
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Dec. 31, 2019
Component of Operating Income [Abstract] |
Schedule of other income | Other income consisted of the following for the years ended December 31, 2019, 2018 and 2017:
| Year Ended December 31,
| 2019 |  | 2018 | 2017
Management fees | $ | 12,445 |  |  | $ | 14,539 |  |  | $ | 13,426 |
Interest and other income | 53,794 |  |  | 47,025 |  |  | 81,172 |
| $ | 66,239 |  |  | $ | 61,564 |  |  | $ | 94,598 |

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