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Goodwill and Intangible Assets - Additional information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Intangible asset amortization	$ 3,849	$ 1,843	$ 499
CSI Electrical Contractors, Inc [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset amortization	1,800
Increase in goodwill	$ 9,500
CSI Electrical Contractors, Inc [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset amortization period	12 years
Trade names [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	15 years
Customer Relationships and Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	12 years 6 months

X

- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Topic 350
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-Paragraph 1
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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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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.

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- Definition

Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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