Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

No definition available.

Name:	dei_AmendmentFlag
Namespace Prefix:	dei_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration

- Definition

PCAOB issued Audit Firm Identifier

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form 10-K
-Number 249
-Section 310

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form 20-F
-Number 249
-Section 220
-Subsection f

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form 40-F
-Number 249
-Section 240
-Subsection f

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2025	Mar. 02, 2026	Jun. 30, 2025
Entity Listings [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2025
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Securities Act File Number	1-33891
Entity Registrant Name	ORION GROUP HOLDINGS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-0097459
Entity Address, Address Line One	2940 Riverby Road, Suite 400
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77020
City Area Code	713
Local Phone Number	852-6500
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction Flag	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		40,083,300
Entity Public Float			$ 360.4
Documents Incorporated by Reference [Text Block]	Portions of the Registrant’s definitive Proxy Statement to be filed in connection with the 2026 Annual Meeting no later than April 30, 2026 are incorporated by reference in Part III of this Annual Report on Form 10-K.
Auditor Firm ID	185
Auditor Name	KPMG LLP
Auditor Location	Houston, Texas
Entity Central Index Key	0001402829
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	FY
Amendment Flag	false
The New York Stock Exchange
Entity Listings [Line Items]
Title of 12(b) Security	Common stock, $0.01 par value per share
Trading Symbol	ORN
Security Exchange Name	NYSE
NYSE Texas
Entity Listings [Line Items]
Title of 12(b) Security	Common stock, $0.01 par value per share
Trading Symbol	ORN
Security Exchange Name	NYSE