Contingencies and Commitments	12 Months Ended
Dec. 31, 2017
Contingencies and Commitments [Abstract]
Contingencies and Commitments	(14) Contingencies and Commitments In 2009, the Company was named a Potentially Responsible Party (“PRP”) in addition to a group of approximately 250 named PRPs under the Comprehensive Environmental Response, Compensation and Liability Act of 1981 (“CERCLA”) with respect to a Superfund site, the Portland Harbor Superfund site (“Portland Harbor”) in Portland, Oregon. The site was declared a Superfund site in December 2000 as a result of historical heavily industrialized use due to manufacturing, shipbuilding, petroleum storage and distribution, metals salvaging, and electrical power generation activities which led to contamination of Portland Harbor, an urban and industrial reach of the lower Willamette River located immediately downstream of downtown Portland. The Company’s involvement arises from four spills at the site after it was declared a Superfund site, as a result of predecessor entities’ actions in the area. To date, there is no information suggesting the extent of the costs or damages to be claimed from the 250 notified PRPs. Based on the nature of the involvement at the Portland Harbor site, the Company believes its potential contribution is de minimis; however, to date neither the Environmental Protection Agency (“EPA”) nor the named PRPs have performed an allocation of potential liability in connection with the site nor have they provided costs and expenses in connection with the site. In January 2015, the Company was named as a defendant in a Complaint filed in the U.S. District Court of the Southern District of Texas, USOR Site PRP Group vs. A&M Contractors, USES, Inc. et al. This is a civil action pursuant to the provisions of CERCLA and the Texas Solid Waste Disposal Act for recovery of past and future response costs incurred and to be incurred by the USOR Site PRP Group for response activities at the U.S. Oil Recovery Superfund Site. The property was a former sewage treatment plant owned by defendant City of Pasadena, Texas from approximately 1945 until it was acquired by U.S. Oil Recovery in January 2009. Throughout its operating life, the U.S. Oil Recovery facility portion of the USOR Site received and performed wastewater pretreatment of municipal and Industrial Class I and Class II wastewater, characteristically hazardous waste, used oil and oily sludges, and municipal solid waste. Associated operations were conducted at the MCC Recycling facility portion of the USOR Site after it was acquired by U.S. Oil Recovery from the City of Pasadena in January 2009. The EPA and the PRP Group entered into an Administrative Settlement Agreement and Order for Remedial Investigation Study (“Study”) in May 2015. The Study has not been completed by EPA to date. The Company filed responsive pleadings in this matter. Based on the nature of the involvement at the USOR Site, the Company believes its potential contribution is de minimis; however, the Study and further review of the Company’s activities at the Site remains ongoing. On October 13, 2016, the Company, as a successor to Hollywood Marine, Inc., was issued a General Notice under CERCLA in which it was named as a PRP for liabilities associated with the SBA Shipyard Site located near Jennings, Louisiana (“Site”). The Site was added to the EPA’s National Priorities List of sites under CERCLA in September 2016. SBA used the facility for construction, repair, retrofitting, sandblasting, and cleaning and painting of barges beginning in 1965. Three barge slips and a dry dock are located off the Mermentau River. The slips were used to dock barges during cleaning or repair. In 2001, a group of PRPs that had been former customers of the SBA Shipyard facility formed an organization called the SSIC Remediation, LLC (hereinafter, “the PRP Group Companies”) to address removal actions at the Site. In 2002, EPA approved an Interim Measures/Removal Action of Hazardous/Principal Threat Wastes at SBA Shipyards, Inc. (pursuant to RCRA Section 3008(h)) that was proposed by SBA Shipyard and the PRP Group Companies. Interim removal activities were conducted from March 2001 through January 2005 under an EPA 2002 Order and Agreement. In September 2012, the Louisiana Department of Environmental Quality requested EPA address the Site under CERCLA authority. The Company, as a successor to Hollywood Marine, Inc., joined the PRP Group Companies. The PRP Group Companies have submitted a draft Study work plan to EPA for their review and comment. Higman Marine, Inc. and affiliated companies ("Higman") was named as a PRP in connection with its activities at the Site. Higman is not a participant in the PRP Group Companies. With respect to the above sites, the Company has recorded reserves, if applicable, for its estimated potential liability for its portion of the EPA’s past costs claim based on information developed to date including various factors such as the Company’s liability in proportion to other responsible parties and the extent to which such costs are recoverable from third parties. On October 13, 2016, the tug Nathan E. Stewart and barge DBL 55, an articulated tank barge and tugboat unit (“ATB”), ran aground at the entrance to Seaforth Channel on Atholone Island, British Columbia. The grounding resulted in a breach of a portion of the Nathan E. Stewart’s fuel tanks causing a discharge of diesel fuel into the water. The USCG and the National Transportation Safety Board (“NTSB”) designated the Company as a party of interest in their investigation as to the cause of the incident. The Canadian authorities including Transport Canada and the Canadian Transportation Safety Board investigated the cause of the incident. The Company is subject to potential claims from third parties as well as the provincial and federal government as a result of the incident. The Company has various insurance policies covering liabilities including pollution, property, marine and general liability and believes that it has satisfactory insurance coverage for the cost of cleanup and salvage operations as well as other potential liabilities arising from the incident. The Company believes it has accrued adequate reserves for the incident and does not expect the incident to have a material adverse effect on its business or financial condition. On March 22, 2014, two tank barges and a towboat (the M/V Miss Susan), owned by Kirby Inland Marine, LP, a wholly owned subsidiary of the Company, were involved in a collision with the M/S Summer Wind on the Houston Ship Channel near Texas City, Texas. The lead tank barge was damaged in the collision resulting in a discharge of intermediate fuel oil from one of its cargo tanks. The USCG and the NTSB named the Company and the Captain of the M/V Miss Susan, as well as the owner and the pilot of the M/S Summer Wind, as parties of interest in their investigation as to the cause of the incident. Sea Galaxy Ltd is the owner of the M/S Summer Wind. The Company is participating in the natural resource damage assessment and restoration process with federal and state government natural resource trustees. The Company believes it has adequate insurance coverage for pollution, marine and other potential liabilities arising from the incident. The Company believes it has accrued adequate reserves for the incident and does not expect the incident to have a material adverse effect on its business or financial condition. In addition, the Company is involved in various legal and other proceedings which are incidental to the conduct of its business, none of which in the opinion of management will have a material effect on the Company’s financial condition, results of operations or cash flows. Management believes that it has recorded adequate reserves and believes that it has adequate insurance coverage or has meritorious defenses for these other claims and contingencies. Certain Significant Risks and Uncertainties. The preparation of financial statements in conformity with United States generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. However, in the opinion of management, the amounts would be immaterial. The customer base of the marine transportation segment includes major industrial petrochemical and chemical manufacturers, refining companies and agricultural chemical manufacturers operating in the United States. During 2017, approximately 75% of marine transportation’s inland revenues were from movements of such products under term contracts, typically ranging from one year to five years, some with renewal options. During 2017, approximately 80% of the marine transportation’s coastal revenues were under term contracts. While the manufacturing and refining companies have generally been customers of the Company for numerous years (some as long as 40 years) and management anticipates a continuing relationship, there is no assurance that any individual contract will be renewed. No single customer of the marine transportation segment accounted for 10% of the Company’s revenues in 2017, 2016 and 2015. Major customers of the distribution and services segment include oilfield service companies, oil and gas operators and producers, inland and offshore barge operators, offshore fishing companies, on-highway transportation companies, mining companies, construction companies, the United States government, and power generation, nuclear and industrial companies. United has maintained continuous exclusive distribution rights for MTU and Allison Transmission products since 1946. United is one of MTU’s top five distributors of MTU off-highway engines in North America with exclusive distribution rights in Oklahoma, Arkansas, Louisiana and Mississippi. In addition, as a distributor of Allison Transmission products, United has distribution rights in Oklahoma, Arkansas and Louisiana. Finally, United is also the distributor for parts service and warranty on Daimler Truck North America (DTNA) engines and related equipment in Oklahoma, Arkansas and Louisiana. S&S is also one of MTU’s top five distributors for off-highway engines with exclusive distribution rights in multiple states. S&S also has authorized exclusive distribution rights for Allison Transmission, Detroit Diesel, Deutz, DTNA, EMD, Rolls Royce Power and Volvo Penta diesel engines in multiple key growth states, primarily through the central, south and eastern parts of the United States and strategically located near major oil and gas fields, marine waterways and on-highway transportation routes. In addition, S&S has long-term relationships with numerous smaller suppliers including Donaldson, Freightliner, Generac and John Deere. Kirby Engine Systems, through Marine Systems and Engine Systems, operates as an authorized EMD distributor throughout the United States. Engine Systems is also the authorized EMD distributor for nuclear power applications worldwide. The relationship with EMD has been maintained for 52 years. The segment also operates factory-authorized full service marine distributorship/dealerships for Cummins, Detroit Diesel and John Deere high-speed diesel engines and Falk, Lufkin and Twin Disc marine gears, as well as an authorized marine dealer for Caterpillar diesel engine in multiple states. The results of the distribution and services segment are largely tied to the industries it serves and, therefore, can be influenced by the cycles of such industries. No single customer of the distribution and services segment accounted for 10% of the Company’s revenues in 2017, 2016 and 2015. Weather can be a major factor in the day-to-day operations of the marine transportation segment. Adverse weather conditions, such as high or low water, tropical storms, hurricanes, tsunamis, fog and ice, can impair the operating efficiencies of the marine fleet. Shipments of products can be delayed or postponed by weather conditions, which are totally beyond the control of the Company. Adverse water conditions are also factors which impair the efficiency of the fleet and can result in delays, diversions and limitations on night passages, and dictate horsepower requirements and size of tows. Additionally, much of the inland waterway system is controlled by a series of locks and dams designed to provide flood control, maintain pool levels of water in certain areas of the country and facilitate navigation on the inland river system. Maintenance and operation of the navigable inland waterway infrastructure is a government function handled by the Army Corps of Engineers with costs shared by industry. Significant changes in governmental policies or appropriations with respect to maintenance and operation of the infrastructure could adversely affect the Company. The Company’s marine transportation segment is subject to regulation by the USCG, federal laws, state laws and certain international conventions, as well as numerous environmental regulations. The Company believes that additional safety, environmental and occupational health regulations may be imposed on the marine industry. There can be no assurance that any such new regulations or requirements, or any discharge of pollutants by the Company, will not have an adverse effect on the Company. The Company’s marine transportation segment competes principally in markets subject to the Jones Act, a federal cabotage law that restricts domestic marine transportation in the United States to vessels built and registered in the United States, and manned and owned by United States citizens. The Jones Act cabotage provisions occasionally come under attack by interests seeking to facilitate foreign flag competition in trades reserved for domestic companies and vessels under the Jones Act. The Company believes that continued efforts will be made to modify or eliminate the cabotage provisions of the Jones Act. If such efforts are successful, certain elements could have an adverse effect on the Company. The Company has issued guaranties or obtained standby letters of credit and performance bonds supporting performance by the Company and its subsidiaries of contractual or contingent legal obligations of the Company and its subsidiaries incurred in the ordinary course of business. The aggregate notional value of these instruments is $21,554,000 at December 31, 2017, including $10,238,000 in letters of credit and $11,316,000 in performance bonds. All of these instruments have an expiration date within four years. The Company does not believe demand for payment under these instruments is likely and expects no material cash outlays to occur in connection with these instruments.

(14) Contingencies and Commitments

In 2009, the Company was named a Potentially Responsible Party (“PRP”) in addition to a group of approximately 250 named PRPs under the Comprehensive Environmental Response, Compensation and Liability Act of 1981 (“CERCLA”) with respect to a Superfund site, the Portland Harbor Superfund site (“Portland Harbor”) in Portland, Oregon. The site was declared a Superfund site in December 2000 as a result of historical heavily industrialized use due to manufacturing, shipbuilding, petroleum storage and distribution, metals salvaging, and electrical power generation activities which led to contamination of Portland Harbor, an urban and industrial reach of the lower Willamette River located immediately downstream of downtown Portland. The Company’s involvement arises from four spills at the site after it was declared a Superfund site, as a result of predecessor entities’ actions in the area. To date, there is no information suggesting the extent of the costs or damages to be claimed from the 250 notified PRPs. Based on the nature of the involvement at the Portland Harbor site, the Company believes its potential contribution is de minimis; however, to date neither the Environmental Protection Agency (“EPA”) nor the named PRPs have performed an allocation of potential liability in connection with the site nor have they provided costs and expenses in connection with the site.

In January 2015, the Company was named as a defendant in a Complaint filed in the U.S. District Court of the Southern District of Texas, USOR Site PRP Group vs. A&M Contractors, USES, Inc. et al. This is a civil action pursuant to the provisions of CERCLA and the Texas Solid Waste Disposal Act for recovery of past and future response costs incurred and to be incurred by the USOR Site PRP Group for response activities at the U.S. Oil Recovery Superfund Site. The property was a former sewage treatment plant owned by defendant City of Pasadena, Texas from approximately 1945 until it was acquired by U.S. Oil Recovery in January 2009. Throughout its operating life, the U.S. Oil Recovery facility portion of the USOR Site received and performed wastewater pretreatment of municipal and Industrial Class I and Class II wastewater, characteristically hazardous waste, used oil and oily sludges, and municipal solid waste. Associated operations were conducted at the MCC Recycling facility portion of the USOR Site after it was acquired by U.S. Oil Recovery from the City of Pasadena in January 2009. The EPA and the PRP Group entered into an Administrative Settlement Agreement and Order for Remedial Investigation Study (“Study”) in May 2015. The Study has not been completed by EPA to date. The Company filed responsive pleadings in this matter. Based on the nature of the involvement at the USOR Site, the Company believes its potential contribution is de minimis; however, the Study and further review of the Company’s activities at the Site remains ongoing.

On October 13, 2016, the Company, as a successor to Hollywood Marine, Inc., was issued a General Notice under CERCLA in which it was named as a PRP for liabilities associated with the SBA Shipyard Site located near Jennings, Louisiana (“Site”). The Site was added to the EPA’s National Priorities List of sites under CERCLA in September 2016. SBA used the facility for construction, repair, retrofitting, sandblasting, and cleaning and painting of barges beginning in 1965. Three barge slips and a dry dock are located off the Mermentau River. The slips were used to dock barges during cleaning or repair. In 2001, a group of PRPs that had been former customers of the SBA Shipyard facility formed an organization called the SSIC Remediation, LLC (hereinafter, “the PRP Group Companies”) to address removal actions at the Site. In 2002, EPA approved an Interim Measures/Removal Action of Hazardous/Principal Threat Wastes at SBA Shipyards, Inc. (pursuant to RCRA Section 3008(h)) that was proposed by SBA Shipyard and the PRP Group Companies. Interim removal activities were conducted from March 2001 through January 2005 under an EPA 2002 Order and Agreement. In September 2012, the Louisiana Department of Environmental Quality requested EPA address the Site under CERCLA authority. The Company, as a successor to Hollywood Marine, Inc., joined the PRP Group Companies. The PRP Group Companies have submitted a draft Study work plan to EPA for their review and comment. Higman Marine, Inc. and affiliated companies ("Higman") was named as a PRP in connection with its activities at the Site. Higman is not a participant in the PRP Group Companies.

With respect to the above sites, the Company has recorded reserves, if applicable, for its estimated potential liability for its portion of the EPA’s past costs claim based on information developed to date including various factors such as the Company’s liability in proportion to other responsible parties and the extent to which such costs are recoverable from third parties.

On October 13, 2016, the tug Nathan E. Stewart and barge DBL 55, an articulated tank barge and tugboat unit (“ATB”), ran aground at the entrance to Seaforth Channel on Atholone Island, British Columbia. The grounding resulted in a breach of a portion of the Nathan E. Stewart’s fuel tanks causing a discharge of diesel fuel into the water. The USCG and the National Transportation Safety Board (“NTSB”) designated the Company as a party of interest in their investigation as to the cause of the incident. The Canadian authorities including Transport Canada and the Canadian Transportation Safety Board investigated the cause of the incident. The Company is subject to potential claims from third parties as well as the provincial and federal government as a result of the incident. The Company has various insurance policies covering liabilities including pollution, property, marine and general liability and believes that it has satisfactory insurance coverage for the cost of cleanup and salvage operations as well as other potential liabilities arising from the incident. The Company believes it has accrued adequate reserves for the incident and does not expect the incident to have a material adverse effect on its business or financial condition.

On March 22, 2014, two tank barges and a towboat (the M/V Miss Susan), owned by Kirby Inland Marine, LP, a wholly owned subsidiary of the Company, were involved in a collision with the M/S Summer Wind on the Houston Ship Channel near Texas City, Texas. The lead tank barge was damaged in the collision resulting in a discharge of intermediate fuel oil from one of its cargo tanks. The USCG and the NTSB named the Company and the Captain of the M/V Miss Susan, as well as the owner and the pilot of the M/S Summer Wind, as parties of interest in their investigation as to the cause of the incident. Sea Galaxy Ltd is the owner of the M/S Summer Wind. The Company is participating in the natural resource damage assessment and restoration process with federal and state government natural resource trustees. The Company believes it has adequate insurance coverage for pollution, marine and other potential liabilities arising from the incident. The Company believes it has accrued adequate reserves for the incident and does not expect the incident to have a material adverse effect on its business or financial condition.

In addition, the Company is involved in various legal and other proceedings which are incidental to the conduct of its business, none of which in the opinion of management will have a material effect on the Company’s financial condition, results of operations or cash flows. Management believes that it has recorded adequate reserves and believes that it has adequate insurance coverage or has meritorious defenses for these other claims and contingencies.

Certain Significant Risks and Uncertainties. The preparation of financial statements in conformity with United States generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. However, in the opinion of management, the amounts would be immaterial.

The customer base of the marine transportation segment includes major industrial petrochemical and chemical manufacturers, refining companies and agricultural chemical manufacturers operating in the United States. During 2017, approximately 75% of marine transportation’s inland revenues were from movements of such products under term contracts, typically ranging from one year to five years, some with renewal options. During 2017, approximately 80% of the marine transportation’s coastal revenues were under term contracts. While the manufacturing and refining companies have generally been customers of the Company for numerous years (some as long as 40 years) and management anticipates a continuing relationship, there is no assurance that any individual contract will be renewed. No single customer of the marine transportation segment accounted for 10% of the Company’s revenues in 2017, 2016 and 2015.

Major customers of the distribution and services segment include oilfield service companies, oil and gas operators and producers, inland and offshore barge operators, offshore fishing companies, on-highway transportation companies, mining companies, construction companies, the United States government, and power generation, nuclear and industrial companies.

United has maintained continuous exclusive distribution rights for MTU and Allison Transmission products since 1946. United is one of MTU’s top five distributors of MTU off-highway engines in North America with exclusive distribution rights in Oklahoma, Arkansas, Louisiana and Mississippi. In addition, as a distributor of Allison Transmission products, United has distribution rights in Oklahoma, Arkansas and Louisiana. Finally, United is also the distributor for parts service and warranty on Daimler Truck North America (DTNA) engines and related equipment in Oklahoma, Arkansas and Louisiana.

S&S is also one of MTU’s top five distributors for off-highway engines with exclusive distribution rights in multiple states. S&S also has authorized exclusive distribution rights for Allison Transmission, Detroit Diesel, Deutz, DTNA, EMD, Rolls Royce Power and Volvo Penta diesel engines in multiple key growth states, primarily through the central, south and eastern parts of the United States and strategically located near major oil and gas fields, marine waterways and on-highway transportation routes. In addition, S&S has long-term relationships with numerous smaller suppliers including Donaldson, Freightliner, Generac and John Deere.

Kirby Engine Systems, through Marine Systems and Engine Systems, operates as an authorized EMD distributor throughout the United States. Engine Systems is also the authorized EMD distributor for nuclear power applications worldwide. The relationship with EMD has been maintained for 52 years. The segment also operates factory-authorized full service marine distributorship/dealerships for Cummins, Detroit Diesel and John Deere high-speed diesel engines and Falk, Lufkin and Twin Disc marine gears, as well as an authorized marine dealer for Caterpillar diesel engine in multiple states.

The results of the distribution and services segment are largely tied to the industries it serves and, therefore, can be influenced by the cycles of such industries. No single customer of the distribution and services segment accounted for 10% of the Company’s revenues in 2017, 2016 and 2015.

Weather can be a major factor in the day-to-day operations of the marine transportation segment. Adverse weather conditions, such as high or low water, tropical storms, hurricanes, tsunamis, fog and ice, can impair the operating efficiencies of the marine fleet. Shipments of products can be delayed or postponed by weather conditions, which are totally beyond the control of the Company. Adverse water conditions are also factors which impair the efficiency of the fleet and can result in delays, diversions and limitations on night passages, and dictate horsepower requirements and size of tows. Additionally, much of the inland waterway system is controlled by a series of locks and dams designed to provide flood control, maintain pool levels of water in certain areas of the country and facilitate navigation on the inland river system. Maintenance and operation of the navigable inland waterway infrastructure is a government function handled by the Army Corps of Engineers with costs shared by industry. Significant changes in governmental policies or appropriations with respect to maintenance and operation of the infrastructure could adversely affect the Company.

The Company’s marine transportation segment is subject to regulation by the USCG, federal laws, state laws and certain international conventions, as well as numerous environmental regulations. The Company believes that additional safety, environmental and occupational health regulations may be imposed on the marine industry. There can be no assurance that any such new regulations or requirements, or any discharge of pollutants by the Company, will not have an adverse effect on the Company.

The Company’s marine transportation segment competes principally in markets subject to the Jones Act, a federal cabotage law that restricts domestic marine transportation in the United States to vessels built and registered in the United States, and manned and owned by United States citizens. The Jones Act cabotage provisions occasionally come under attack by interests seeking to facilitate foreign flag competition in trades reserved for domestic companies and vessels under the Jones Act. The Company believes that continued efforts will be made to modify or eliminate the cabotage provisions of the Jones Act. If such efforts are successful, certain elements could have an adverse effect on the Company.

The Company has issued guaranties or obtained standby letters of credit and performance bonds supporting performance by the Company and its subsidiaries of contractual or contingent legal obligations of the Company and its subsidiaries incurred in the ordinary course of business. The aggregate notional value of these instruments is $21,554,000 at December 31, 2017, including $10,238,000 in letters of credit and $11,316,000 in performance bonds. All of these instruments have an expiration date within four years. The Company does not believe demand for payment under these instruments is likely and expects no material cash outlays to occur in connection with these instruments.