Consolidated Entities, Ownership Percentage

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- Definition

Contracts Receivable Retainage, Percentage Estimated To Be Collected In Next Fiscal Year

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- Definition

Lease, Operating Lease, Remaining Term

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- Definition

Represents the length of time the Company's contracts generally take to complete.

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- Definition

Amount billed to customers under long-term contracts or programs that have been withheld because of retainage provisions in a contract.

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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.

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- Definition

Discount rate used by lessee to determine present value of operating lease payments.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Summary of Business and Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Consolidated ownership percentage	50.00%
Contract receivable retainage	$ 79,400		$ 47,400
Retainage rate	75.00%
Operating lease right-of-use assets	$ 13,979	$ 13,600
Operating lease liability, current	7,095	6,200
Operating lease liability, noncurrent	$ 6,976	$ 7,400
Operating leases	2 years 6 months 7 days
Operating leases	6.00%
Other Current Assets
Financing Receivable, Impaired [Line Items]
Restricted cash	$ 4,800		$ 3,900
Building and improvements \| Minimum
Financing Receivable, Impaired [Line Items]
Property, plant and equipment, useful life	5 years
Building and improvements \| Maximum
Financing Receivable, Impaired [Line Items]
Property, plant and equipment, useful life	39 years
Plant and field equipment \| Minimum
Financing Receivable, Impaired [Line Items]
Property, plant and equipment, useful life	5 years
Plant and field equipment \| Maximum
Financing Receivable, Impaired [Line Items]
Property, plant and equipment, useful life	20 years
Heavy Civil Construction \| Minimum
Financing Receivable, Impaired [Line Items]
Revenue recognition, percentage of completion range	12 months
Heavy Civil Construction \| Maximum
Financing Receivable, Impaired [Line Items]
Revenue recognition, percentage of completion range	36 months
Specialty Service \| Minimum
Financing Receivable, Impaired [Line Items]
Revenue recognition, percentage of completion range	6 months
Specialty Service \| Maximum
Financing Receivable, Impaired [Line Items]
Revenue recognition, percentage of completion range	24 months