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v3.21.1

Revenues and Accounts Receivable - Additional Information (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 USD ($) Customer | Mar. 31, 2020 USD ($) Customer | Dec. 31, 2020 USD ($)
Accounts Notes And Loans Receivable [Line Items] |  |  |
Contracts assets acquired through business acquisitions | $ 500 |  | $ 6,500
Contract liabilities acquired through business acquisitions | 500 |  | 0
Contract with customer liabilities, revenue recognized | 1,200 |  |
Revenue remaining performance obligations | 25,400 |  | 24,400
Bad debt reserve | $ 508 | $ 6,333 | $ 4,532
Remediation and Reuse Segment |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Bad debt reserve |  | $ 5,500 |
Customer Concentration Risk | Accounts Receivable | One Customer |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Concentration risk percentage | 15.90% |  | 10.20%
Customer Concentration Risk | Revenue |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Concentration risk percentage |  | 10.00% |
Number of customers | Customer | 3 | 0 |
Customer Concentration Risk | Revenue | One Customer |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Concentration risk percentage | 16.30% |  |
Customer Concentration Risk | Revenue | Customer Two |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Concentration risk percentage | 12.70% |  |
Customer Concentration Risk | Revenue | Customer Three |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Concentration risk percentage | 10.20% |  |

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