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v3.21.1

Subsequent Events - Additional Information (Details) - USD ($) |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
Apr. 27, 2021 | Apr. 01, 2021 | Apr. 13, 2020 | Jan. 31, 2021 | Apr. 30, 2020 | Mar. 31, 2021 | Dec. 31, 2020
Subsequent Event [Line Items] |  |  |  |  |  |  |
Number of common stock shares issued in connection with business acquisition |  |  |  |  |  | 71,740 |
Cash |  |  |  |  |  |  | $ 175,450,000
Credit facility maturity date |  |  | Apr. 30, 2025 |  |  |  |
Incremental Term Loans |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  | $ 100,000,000 |  |  |  |
CTEH |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Number of common stock shares issued in connection with business acquisition |  |  |  |  | 791,139 |  |
Cash |  |  |  |  |  |  | $ 175,000,000
MSE Group |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Number of common stock shares issued in connection with business acquisition |  |  |  |  |  | 71,740 |
Cash |  |  |  | $ 9,082,000 |  |  |
Subsequent Event | 2021 Credit Facility |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity | $ 300,000,000 |  |  |  |  |  |
Credit facility maturity date | Apr. 27, 2026 |  |  |  |  |  |
Percentage of interest rate adjustment | 0.05% |  |  |  |  |  |
Maximum net leverage ratio | 425.00% |  |  |  |  |  |
Maximum net leverage ratio year two | 400.00% |  |  |  |  |  |
Maximum net leverage ratio year three | 375.00% |  |  |  |  |  |
Minimum fixed charge coverage ratio | 125.00% |  |  |  |  |  |
Subsequent Event | Incremental Term Loans |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity | $ 150,000,000 |  |  |  |  |  |
Subsequent Event | Term Loan Facility | 2021 Credit Facility |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity | 175,000,000 |  |  |  |  |  |
Subsequent Event | Revolving Line of Credit | 2021 Credit Facility |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity | 125,000,000 |  |  |  |  |  |
Subsequent Event | Revolving Line of Credit | Letter of Credit | 2021 Credit Facility |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity | $ 20,000,000 |  |  |  |  |  |
Subsequent Event | CTEH |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Number of common stock shares issued in connection with business acquisition |  | 539,607 |  |  |  |  |
Shares issued, price per share |  | $ 46.33 |  |  |  |  |
Cash |  | $ 25,000,000 |  |  |  |  |
Subsequent Event | MSE Group |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Number of common stock shares issued in connection with business acquisition |  | 24,200 |  |  |  |  |
Shares issued, price per share |  | $ 44.81 |  |  |  |  |
Cash |  | $ 8,000,000 |  |  |  |  |

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