Contract Assets and Liabilities - Schedule of Change in Contract Liability Balance (Details) $ in Thousands	6 Months Ended
Jun. 30, 2018 USD ($)
Revenue From Contract With Customer [Abstract]
Balance at January 1, 2018	$ 83,674
Change in the measure of progress on projects, net	(620,602)
Acquired contract liabilities	7,974
Revisions in estimates, net	(4,353)
Billings	625,434
Change in provision for loss, net	(263)
Balance at June 30, 2018	$ 91,864

Contract with customer billings liability.

No definition available.

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Balance Type:	credit
Period Type:	duration

- Definition

Contract With Customer Liabilities Accumulated Allowance For Credit Loss

+ References

No definition available.

+ Details

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Namespace Prefix:	gva_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Contract with customer liability balance.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130551-203045

+ Details

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Balance Type:	credit
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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 obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration from customer has been received or is due, from business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130551-203045

+ Details

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Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

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