Description of Business and Basis of Presentation	12 Months Ended
Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Basis of Presentation	Description of Business and Basis of Presentation Description of Business Orion Group Holdings, Inc., its subsidiaries and affiliates (hereafter collectively referred to as the "Company"), is a leading specialty construction company in the building, industrial, and infrastructure sectors in the continental United States, Alaska, Canada and the Caribbean Basin through its heavy civil marine construction and its commercial concrete construction segments. The Company’s heavy civil marine construction segment services include marine transportation facility construction, marine pipeline construction, marine environmental structures, dredging of waterways, channels and ports, environmental dredging, design, and specialty services. Its commercial concrete construction segment provides turnkey concrete construction services including pour and finish, dirt work, layout, forming, rebar, and mesh across the light commercial structural and other associated business areas. The Company is headquartered in Houston, Texas with offices throughout its operating areas. The tools used by the chief operating decision maker to allocate resources and assess performance are based on two reportable and operating segments: heavy civil marine construction and commercial concrete construction. Although the Company describes its business in this report in terms of the services it provides, our base of customers and the areas in which it operates, it has determined that its operations currently comprise two reportable segments pursuant to FASB ASC Topic 280 - Segment Reporting. In previous reporting periods, the Company reported its financial information based on one reportable segment, now known as the heavy civil marine construction segment. With the acquisition of TAS in 2015, we expanded to two operating and reportable segments, adding the commercial concrete construction segment. In making this determination, the Company considered the similar economic characteristics of its operations. For the heavy civil marine construction segment, the methods used, and the internal processes employed, to deliver heavy civil marine construction services are similar throughout the segment, including standardized estimating, project controls and project management. This segment has the same customers with similar funding drivers, and it complies with regulatory environments driven through Federal agencies such as the U.S. Army Corps of Engineers, U.S. Fish and Wildlife Service, EPA and OSHA, among others. Additionally, the segment is driven by macro-economic considerations including the level of import/export seaborne transportation, development of energy related infrastructure, cruise line expansion and operations, marine bridge infrastructure development, waterway pipeline crossings and the maintenance of waterways. These considerations, and others, are key catalysts for future prospects and are similar across the segment. For our commercial concrete construction segment, the Company also considered the similar economic characteristics of these operations. The methods used, and the internal processes employed to deliver our commercial concrete construction services are similar throughout the segment, including standardized estimating, project controls and project management. This segment complies with regulatory environments such as OSHA. Additionally, this segment is driven by macro-economic considerations, including movements in population, commercial real estate development, institutional funding and expansion, and recreational developments, specifically in metropolitan areas of Texas. These considerations, and others, are key catalysts for future prospects and are similar across the segment. Basis of Presentation These consolidated financial statements include the accounts of the parent company, Orion Group Holdings, Inc. and its wholly-owned subsidiaries and have been prepared in accordance with accounting principles generally accepted in the United States of America. All intercompany balances and transactions have been eliminated in consolidation.

Description of Business and Basis of Presentation

Description of Business

Orion Group Holdings, Inc., its subsidiaries and affiliates (hereafter collectively referred to as the "Company"), is a leading specialty construction company in the building, industrial, and infrastructure sectors in the continental United States, Alaska, Canada and the Caribbean Basin through its heavy civil marine construction and its commercial concrete construction segments. The Company’s heavy civil marine construction segment services include marine transportation facility construction, marine pipeline construction, marine environmental structures, dredging of waterways, channels and ports, environmental dredging, design, and specialty services. Its commercial concrete construction segment provides turnkey concrete construction services including pour and finish, dirt work, layout, forming, rebar, and mesh across the light commercial structural and other associated business areas. The Company is headquartered in Houston, Texas with offices throughout its operating areas.

The tools used by the chief operating decision maker to allocate resources and assess performance are based on two reportable and operating segments: heavy civil marine construction and commercial concrete construction.

Although the Company describes its business in this report in terms of the services it provides, our base of customers and the areas in which it operates, it has determined that its operations currently comprise two reportable segments pursuant to FASB ASC Topic 280 - Segment Reporting. In previous reporting periods, the Company reported its financial information based on one reportable segment, now known as the heavy civil marine construction segment. With the acquisition of TAS in 2015, we expanded to two operating and reportable segments, adding the commercial concrete construction segment.

In making this determination, the Company considered the similar economic characteristics of its operations. For the heavy civil marine construction segment, the methods used, and the internal processes employed, to deliver heavy civil marine construction services are similar throughout the segment, including standardized estimating, project controls and project management. This segment has the same customers with similar funding drivers, and it complies with regulatory environments driven through Federal agencies such as the U.S. Army Corps of Engineers, U.S. Fish and Wildlife Service, EPA and OSHA, among others. Additionally, the segment is driven by macro-economic considerations including the level of import/export seaborne transportation, development of energy related infrastructure, cruise line expansion and operations, marine bridge infrastructure development, waterway pipeline crossings and the maintenance of waterways. These considerations, and others, are key catalysts for future prospects and are similar across the segment.

For our commercial concrete construction segment, the Company also considered the similar economic characteristics of these operations. The methods used, and the internal processes employed to deliver our commercial concrete construction services are similar throughout the segment, including standardized estimating, project controls and project management. This segment complies with regulatory environments such as OSHA. Additionally, this segment is driven by macro-economic considerations, including movements in population, commercial real estate development, institutional funding and expansion, and recreational developments, specifically in metropolitan areas of Texas. These considerations, and others, are key catalysts for future prospects and are similar across the segment.

Basis of Presentation

These consolidated financial statements include the accounts of the parent company, Orion Group Holdings, Inc. and its wholly-owned subsidiaries and have been prepared in accordance with accounting principles generally accepted in the United States of America. All intercompany balances and transactions have been eliminated in consolidation.