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Revenues and Accounts Receivable - Schedule of Accounts Receivable, Net (Details) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
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Revenues And Accounts Receivable [Abstract] |  |  |
Accounts receivable, invoiced | $ 64,314 | $ 57,228 |
Accounts receivable, other | 5,766 | 1,139 |
Allowance for doubtful accounts | (4,309) | (4,265) | $ (1,327)
Accounts receivable—net | $ 65,771 | $ 54,102 |

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