The rate of retention provision on a contract with customer.

No definition available.

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- Definition

Percentage of increase (decrease) cost estimate revision gross margin.

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Indicates (true false) whether lessee has option to extend operating and finance leases.

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Lessee, operating and finance leases, option to extend, term.

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Lessee, operating and finance leases, option to terminate, period.

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Lessee operating and finance leases remaining contract term.

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- Definition

amount of Deductible Insurance Policy for Loss Contingency

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No definition available.

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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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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.

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- Definition

Amount of accumulated credit loss for right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in estimate of transaction price which (increases) decreases obligation to transfer good or service to customer for which consideration from customer has been received or is due. Includes, but is not limited to, change in assessment of whether estimate of variable consideration is constrained.

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- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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Organization, Business and Significant Accounting Policies (Details) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares	Sep. 30, 2019 USD ($) $ / shares	Jun. 30, 2019 USD ($) $ / shares	Mar. 31, 2019 USD ($) $ / shares	Dec. 31, 2018 USD ($) $ / shares	Sep. 30, 2018 USD ($) $ / shares	Jun. 30, 2018 USD ($) $ / shares	Mar. 31, 2018 USD ($) $ / shares	Dec. 31, 2019 USD ($) segment $ / shares	Dec. 31, 2018 USD ($) $ / shares	Dec. 31, 2017 USD ($) $ / shares
Organization Consolidation and Presentation of Financial Statements [Line Items]
Number of business segments (segment) \| segment									2
Contract retention provision									10.00%
Foreign currency gains									$ 100
Revenue recognized, related to change orders and claims included as contract price adjustments									35,900	$ 3,400
Increase (decrease) in operating income									57,178	50,312	$ 29,558
Increase (decrease) in net income	$ 12,775	$ 10,355	$ 7,207	$ 7,353	$ 10,651	$ 7,957	$ 6,835	$ 5,644	$ 37,690	$ 31,087	$ 21,154
Increase (decrease) in diluted earnings per common share (in dollars per share) \| $ / shares	$ 0.76	$ 0.62	$ 0.43	$ 0.44	$ 0.64	$ 0.48	$ 0.41	$ 0.34	$ 2.26	$ 1.87	$ 1.28
Advertising cost									$ 800	$ 700	$ 700
Allowance for contract retainage	$ 0				$ 0				$ 0	$ 0
Concentration risk									100.00%	100.00%
Existence of option to extend lease									true
Option to extend lease term (up to)									5 years
Option to terminate leases, period									1 year
T&D [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Increase (decrease) in operating income									$ 73,580	$ 57,242	$ 39,631
Contingencies Excluding Wildfire and Health Insurance [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Insurance coverage deductible	1,000								1,000
Wildfire [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Insurance coverage deductible	2,000								2,000
Health Insurance [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Insurance coverage deductible	$ 200								$ 200
Maximum [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Remaining lease term									7 years
Minimum [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Remaining lease term									1 year
Revenue from Contract with Customer [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Concentration risk									100.00%	100.00%
Revenue from Contract with Customer [Member] \| Top Ten Customers [Member] \| Customer Concentration Risk [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Concentration risk									30.80%	32.90%	40.40%
Revenue from Contract with Customer [Member] \| Top One Customer [Member] \| Customer Concentration Risk [Member] \| T&D [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Concentration risk											10.70%
Labor employees covered by collective bargaining agreements [Member] \| Labor Force Concentration Risk [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Concentration risk									90.00%
Contracts Accounted for under Percentage of Completion [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Increase (decrease) in consolidated gross margin									(0.80%)	(0.70%)	(0.70%)
Increase (decrease) in operating income									$ (11,700)	$ (10,500)	$ (10,400)
Increase (decrease) in net income									$ (7,500)	$ (8,200)	$ (6,200)
Increase (decrease) in diluted earnings per common share (in dollars per share) \| $ / shares									$ (0.45)	$ (0.49)	$ (0.38)