Contracts with customer assets acquired through business acquisitions.

No definition available.

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- Definition

Contracts with customer liabilities acquired through business acquisitions.

+ References

No definition available.

+ Details

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- Definition

Number of customers.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
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-Topic 825
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

+ Details

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130549-203045

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section S99
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-Subparagraph (SX 210.5-03(5))
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

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- Definition

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130556-203045

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- Details

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- Details

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- Details

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- Details

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Revenues and Accounts Receivable - Additional Information (Details) $ in Thousands	3 Months Ended			6 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2021 USD ($) Customer	Sep. 30, 2020 Customer	Mar. 31, 2020 USD ($)	Jun. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) Customer	Sep. 30, 2020 USD ($) Customer	Dec. 31, 2020 USD ($)
Accounts Notes And Loans Receivable [Line Items]
Contracts assets acquired through business acquisitions					$ 400		$ 6,500
Contract liabilities acquired through business acquisitions					500		0
Contract with customer liabilities, revenue recognized	$ 1,300				3,800
Revenue remaining performance obligations	$ 64,100				64,100		24,400
Bad debt reserve			$ 6,300		$ 803	$ 6,445	$ 4,532
Remediation and Reuse Segment
Accounts Notes And Loans Receivable [Line Items]
Bad debt reserve				$ 5,500
Customer Concentration Risk \| Accounts Receivable \| Customer One
Accounts Notes And Loans Receivable [Line Items]
Concentration risk percentage					10.00%		10.20%
Customer Concentration Risk \| Revenue
Accounts Notes And Loans Receivable [Line Items]
Number of customers \| Customer	0	0			3	0
Customer Concentration Risk \| Revenue \| Customer One
Accounts Notes And Loans Receivable [Line Items]
Concentration risk percentage					12.10%
Customer Concentration Risk \| Revenue \| Significant Customer
Accounts Notes And Loans Receivable [Line Items]
Concentration risk percentage	10.00%	10.00%				10.00%
Customer Concentration Risk \| Revenue \| Customer Two
Accounts Notes And Loans Receivable [Line Items]
Concentration risk percentage					11.40%
Customer Concentration Risk \| Revenue \| Customer Three
Accounts Notes And Loans Receivable [Line Items]
Concentration risk percentage					10.70%