Aggregate affirmative claim recovery estimate included in contract asset and liability balances.

No definition available.

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Namespace Prefix:	gva_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of revenue recognized including opening balance of contract with customer liability.

+ References

No definition available.

+ Details

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

- Definition

The amount of retention from contracts with customers.

+ References

No definition available.

+ Details

Name:	gva_ContractWithCustomerRetention
Namespace Prefix:	gva_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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://www.xbrl.org/2003/role/exampleRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-10

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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.

+ Details

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Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=gva_BrightlineTrainsFloridaLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=gva_PerformanceObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Contract Assets and Liabilities - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Product Information [Line Items]
Claim recovery estimates	$ 27,200		$ 27,200		$ 46,600
Contract retention	162,531		162,531		188,917
Revenue recognized	28,500	$ 16,700	341,400	$ 270,000
Customer Concentration Risk \| Accounts Receivable \| Brightline Trains Florida LLC
Product Information [Line Items]
Contract retention					$ 29,200
Performance Obligations
Product Information [Line Items]
Revenue adjustment	$ 47,300	$ 43,300	$ 165,600	$ 220,700