Revenue - Summary of Significant Changes in Asset and Liability Balances (Detail) - Centuri Construction Group Inc [Member] $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)
Amounts Billed in Excess of Revenue Earned on Contracts [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue recognized that was included in the amounts billed in excess of revenue earned on contracts balance at the beginning of the period	$ (9,602)
Increases due to amounts billed to customers in excess of revenue earned during the period	8,102
Revenue Earned on Contracts in Progress in Excess of Billings [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Transferred to contracts receivable from revenue earned on contracts in progress in excess of billings recognized at the beginning of the period	(5,768)
Increase from the reclassification of contract assets due to the adoption of topic 606	51,744
Increases from contract assets, contingent on a future event occurring	$ 6,001

Increases due to amounts billed to customers in excess of revenue earned during the period.

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- Definition

Increases from contract assets, contingent on a future event occurring

+ References

No definition available.

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- Definition

Revenue recognized that included in amounts billed in excess of revenue earned on contracts.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which increases (decreases) right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130551-203045

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- Definition

Amount of decrease in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time from transfer to receivable due to right to consideration becoming unconditional.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130551-203045

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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.

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