Business Acquisitions - Additional Information (Details) - USD ($)		1 Months Ended			3 Months Ended
	Apr. 01, 2021	Apr. 30, 2021	Jan. 31, 2021	Apr. 30, 2020	Mar. 31, 2021	Mar. 31, 2020
Business Acquisition [Line Items]
Transaction costs related to business combinations					$ 237,000	$ 1,307,000
Number of common stock shares issued in connection with business acquisition					71,740
Revenues from discontinued service lines					$ 0	$ 2,500,000
MSE Group
Business Acquisition [Line Items]
Percentage of interests acquired			100.00%
Number of common stock shares issued in connection with business acquisition					71,740
Revenue					$ 4,000,000
Pre-tax loss					$ 300,000
MSE Group | Subsequent Event
Business Acquisition [Line Items]
Number of common stock shares issued in connection with business acquisition	24,200
MSE Group | Customer Relationships
Business Acquisition [Line Items]
Weighted average useful lives for acquired intangible assets			7 years
MSE Group | Related Backlog
Business Acquisition [Line Items]
Weighted average useful lives for acquired intangible assets			2 years
MSE Group | Trade Names
Business Acquisition [Line Items]
Weighted average useful lives for acquired intangible assets			2 years
MSE Group | Covenants Not to Compete
Business Acquisition [Line Items]
Weighted average useful lives for acquired intangible assets			5 years
MSE Group | 2022 Earn Out
Business Acquisition [Line Items]
Business combination, earn-out payment, maximum			$ 6,200,000
MSE Group | 2023 Earn Out
Business Acquisition [Line Items]
Business combination, earn-out payment, maximum			$ 6,200,000
CTEH
Business Acquisition [Line Items]
Percentage of interests acquired				100.00%
Number of common stock shares issued in connection with business acquisition				791,139
CTEH | External Proprietary Software
Business Acquisition [Line Items]
Weighted average useful lives for acquired intangible assets				5 years
CTEH | Subsequent Event
Business Acquisition [Line Items]
Number of common stock shares issued in connection with business acquisition	539,607
CTEH | Customer Relationships
Business Acquisition [Line Items]
Weighted average useful lives for acquired intangible assets				15 years
CTEH | Trade Names
Business Acquisition [Line Items]
Weighted average useful lives for acquired intangible assets				5 years
CTEH | Covenants Not to Compete
Business Acquisition [Line Items]
Weighted average useful lives for acquired intangible assets				5 years
CTEH | Proprietary Software
Business Acquisition [Line Items]
Weighted average useful lives for acquired intangible assets				3 years
CTEH | 2020 Earn Out
Business Acquisition [Line Items]
Business combination, earn-out payment, maximum				$ 50,000,000
Business combination, contingent consideration arrangements, basis for amount					The CTEH first year earn-out was calculated at twelve times CTEH’s 2020 EBITDA (as defined in the purchase agreement) in excess of $18.3 million, with a maximum first year earn-out payment of $50.0 million, which was fully achieved.
Business combination, contingent consideration arrangements, description					The 2020 earn-out was initially payable 100.0% in common stock, but as a result of the completion of the Company’s IPO (Note 1), 50.0% was payable in cash. In April 2021, the 2020 earn-out payment was made with 50.0% paid in cash and the remaining 50.0% paid in common stock of the Company (Note 22).
Business combination, minimum EBITDA for contingent consideration arrangements				$ 18,300,000
Percentage of earn out payable in common stock				100.00%
CTEH | 2020 Earn Out | Subsequent Event
Business Acquisition [Line Items]
Percentage of earn out paid in cash, as result of completing of IPO		50.00%
Percentage of earn out paid in common stock, as a result of completion of IPO		50.00%
CTEH | 2020 Earn Out | Minimum
Business Acquisition [Line Items]
Business combination, actual EBITDA				$ 18,300,000
CTEH | 2020 Earn Out | Maximum
Business Acquisition [Line Items]
Business combination, actual EBITDA				22,500,000
CTEH | 2021 Earn Out
Business Acquisition [Line Items]
Business combination, earn-out payment, maximum				$ 30,000,000
Business combination, contingent consideration arrangements, basis for amount					The second year earn-out is to be calculated at ten times CTEH’s 2021 EBITDA in excess of actual 2020 EBITDA (with actual 2020 EBITDA subject to a minimum of $18.3 million and a maximum of $22.5 million), with a maximum second year earn-out payment of $30.0 million.
Business combination, contingent consideration arrangements, description					The 2021 earn-out, if any, is payable 100.0% in cash.
Percentage of earn out payable in cash				100.00%
Other Acquisition | Covenants Not to Compete
Business Acquisition [Line Items]
Weighted average useful lives for acquired intangible assets				4 years