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v3.20.4

Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2020
Summary of Significant Accounting Policies |
Components of self-insurance reserves | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31,
​ |  | 2020 |  | 2019
Self-insurance reserves (undiscounted) | ​ | $ | 213,332 | ​ | $ | 168,397
Self-insurance reserves (discounted) | ​ |  | 202,454 | ​ |  | 156,585

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