Principles of Consolidation and Basis of Presentation	9 Months Ended
Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Principles of Consolidation and Basis of Presentation	PRINCIPLES OF CONSOLIDATION AND BASIS OF PRESENTATION: The interim consolidated financial statements presented herein include the accounts of Genesee & Wyoming Inc. and its subsidiaries. All significant intercompany transactions and accounts have been eliminated in consolidation. These interim consolidated financial statements have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (SEC) and are unaudited. They do not contain all disclosures which would be required in a full set of financial statements prepared in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP). In the opinion of management, the unaudited financial statements for the three and nine months ended September 30, 2018 and 2017 are presented on a basis consistent with the audited financial statements and contain all adjustments, consisting only of normal recurring adjustments, necessary to provide a fair statement of the results for the interim periods presented. The results of operations for interim periods are not necessarily indicative of results of operations for the full year. The consolidated balance sheet data for 2017 was derived from the audited financial statements in the Company's 2017 Annual Report on Form 10-K, but does not include all disclosures required by U.S. GAAP. The results of operations of the foreign entities are maintained in the local currency of the respective subsidiary and translated into United States dollars at the applicable exchange rates for inclusion in the consolidated financial statements. As a result, any appreciation or depreciation of these currencies against the United States dollar will impact the Company's results of operations. The interim consolidated financial statements should be read in conjunction with the audited financial statements and notes thereto for the year ended December 31, 2017 included in the Company's 2017 Annual Report on Form 10-K. Certain reclassifications and adjustments have been made to prior period balances to conform to the current year presentation as noted below. On January 1, 2018, the Company adopted ASU 2017-07, Compensation-Retirement Benefits (Topic 715), Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost. Prior to the adoption of ASU 2017-07, the Company presented net pension costs within operating income on the same line item as other compensation costs arising from services rendered by the applicable employees. ASU 2017-07 requires that net pension costs, other than service cost, be presented outside of operating income. The Company applied these changes retrospectively to its consolidated statement of operations which resulted in a $1.6 million and $4.8 million decrease in operating income and a corresponding change in other income/(loss), net for the three and nine months ended September 30, 2017, respectively. The adjustments had no impact on net income. On January 1, 2018, the Company adopted ASU 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220), Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. The current standard, ASC Topic 740, requires deferred tax liabilities to be adjusted for the effect of a change in tax laws or rates with the effect included in income from operations in the reporting period of the enactment date. The Tax Cuts and Jobs Act of 2017 (the TCJA) enacted by the Unites States federal government resulted in tax effects of items recorded within accumulated other comprehensive income (AOCI) or accumulated other comprehensive loss (AOCL), as the case may be, to be "stranded," as those items no longer reflect the appropriate tax rate. This amendment allows the reclassification from AOCI/AOCL to retained earnings for the stranded tax effects resulting from the new income tax rates. The Company applied the amendments as of January 1, 2018 by reclassifying $3.0 million from AOCL to retained earnings, eliminating the stranded tax effects in AOCL resulting from the TCJA. This reclassification reduced AOCL and increased retained earnings by $3.0 million. It is the Company's policy to release income tax effects from AOCI/AOCL using the item-by-item approach. On January 1, 2018, the Company adopted ASU 2014-09, Revenue from Contracts with Customers, which supersedes previous revenue guidance. The standard requires that the Company recognize revenue when it transfers the promised goods or services to customers in an amount that reflects the consideration the Company expects to receive in exchange for those goods or services. The Company adopted ASU 2014-09 and all related amendments using the modified retrospective approach. Under the standard, the Company continues to recognize freight revenue proportionally as a shipment moves from origin to destination. The adoption did not affect the Company’s financial condition, results of operations or liquidity. Disclosures related to the nature, amount and timing of revenue and cash flows resulting from contracts with customers are included in Note 4, Revenue. On December 1, 2016, a subsidiary of the Company completed the acquisition of Glencore Rail (NSW) Pty Limited (GRail) and concurrently issued a 48.9% stake in G&W Australia Holdings LP (GWAHLP) (collectively, the Australia Partnership), which is the holding entity for all of the Company’s Australian businesses, including GRail, to a consortium of funds and clients managed by Macquarie Infrastructure and Real Assets (MIRA), a large infrastructure investment firm. The Company, through wholly-owned subsidiaries, also made incremental investments and retained a 51.1% ownership in GWAHLP. The investments made by both the Company and MIRA consisted of equity and debt financing of GWAHLP in similar proportions. As MIRA's investments were made at the contemporaneous fair value of GWAHLP as of December 1, 2016, accounting for MIRA's noncontrolling interest in the Company's consolidated financial statements required adjustments to reflect a proportional interest in the net book value of GWAHLP. During the three months ended March 31, 2018, the Company determined that there was an error in its December 1, 2016 calculation of the noncontrolling interest for MIRA's 48.9% equity interest, which resulted in the following adjustment within the total equity section of the Company's consolidated balance sheet: a decrease in noncontrolling interest of $71.9 million, an increase in additional paid-in capital of $57.9 million and a decrease in AOCL of $14.0 million. This revision has been reflected in the Company's consolidated balance sheet as of December 31, 2017 as well as the December 31, 2016 equity balances as disclosed in the Company's consolidated statements of changes in equity. There was no effect on any other section of the Company's balance sheet. This revision had no impact on the Company's consolidated statements of operations, comprehensive income or cash flows for the three and nine months ended September 30, 2018 and 2017. The Company does not consider this revision material to any previously issued consolidated financial statements. When comparing the Company's results of operations from one reporting period to another, it is important to consider that the Company has historically experienced fluctuations in revenues and expenses due to acquisitions, changing economic conditions, fluctuations in commodity prices, competitive forces, changes in foreign currency exchange rates, rail network issues and congestion, the ability to attract and retain skilled workers, one-time freight moves, fuel price fluctuations, customer plant expansions and shutdowns, sales of property and equipment, derailments and weather-related conditions, such as hurricanes, cyclones, tornadoes, high winds, droughts, heavy snowfall, unseasonably hot or cold weather, freezing and flooding, among other factors. In periods when these events occur, the Company's results of operations are not easily comparable from one period to another. Finally, certain of the Company's railroads have commodity shipments that are sensitive to general economic conditions, global commodity prices and foreign exchange rates, such as steel products, iron ore, paper products, lumber and forest products and agricultural products, as well as product specific market conditions, such as the availability of lower priced alternative sources of power generation (coal) and energy commodity price differentials (crude oil and natural gas liquids) or congestion at ports (intermodal). Other shipments are relatively less affected by economic conditions and are more closely affected by other factors, such as winter weather (salt) and seasonal rainfall (agricultural products). As a result of these and other factors, the Company's results of operations in any reporting period may not be directly comparable to the Company's results of operations in other reporting periods.

PRINCIPLES OF CONSOLIDATION AND BASIS OF PRESENTATION:

The interim consolidated financial statements presented herein include the accounts of Genesee & Wyoming Inc. and its subsidiaries. All significant intercompany transactions and accounts have been eliminated in consolidation. These interim consolidated financial statements have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (SEC) and are unaudited. They do not contain all disclosures which would be required in a full set of financial statements prepared in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP). In the opinion of management, the unaudited financial statements for the three and nine months ended September 30, 2018 and 2017 are presented on a basis consistent with the audited financial statements and contain all adjustments, consisting only of normal recurring adjustments, necessary to provide a fair statement of the results for the interim periods presented. The results of operations for interim periods are not necessarily indicative of results of operations for the full year. The consolidated balance sheet data for 2017 was derived from the audited financial statements in the Company's 2017 Annual Report on Form 10-K, but does not include all disclosures required by U.S. GAAP.

The results of operations of the foreign entities are maintained in the local currency of the respective subsidiary and translated into United States dollars at the applicable exchange rates for inclusion in the consolidated financial statements. As a result, any appreciation or depreciation of these currencies against the United States dollar will impact the Company's results of operations.

The interim consolidated financial statements should be read in conjunction with the audited financial statements and notes thereto for the year ended December 31, 2017 included in the Company's 2017 Annual Report on Form 10-K. Certain reclassifications and adjustments have been made to prior period balances to conform to the current year presentation as noted below.

On January 1, 2018, the Company adopted ASU 2017-07, Compensation-Retirement Benefits (Topic 715), Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost. Prior to the adoption of ASU 2017-07, the Company presented net pension costs within operating income on the same line item as other compensation costs arising from services rendered by the applicable employees. ASU 2017-07 requires that net pension costs, other than service cost, be presented outside of operating income. The Company applied these changes retrospectively to its consolidated statement of operations which resulted in a $1.6 million and $4.8 million decrease in operating income and a corresponding change in other income/(loss), net for the three and nine months ended September 30, 2017, respectively. The adjustments had no impact on net income.

On January 1, 2018, the Company adopted ASU 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220), Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. The current standard, ASC Topic 740, requires deferred tax liabilities to be adjusted for the effect of a change in tax laws or rates with the effect included in income from operations in the reporting period of the enactment date. The Tax Cuts and Jobs Act of 2017 (the TCJA) enacted by the Unites States federal government resulted in tax effects of items recorded within accumulated other comprehensive income (AOCI) or accumulated other comprehensive loss (AOCL), as the case may be, to be "stranded," as those items no longer reflect the appropriate tax rate. This amendment allows the reclassification from AOCI/AOCL to retained earnings for the stranded tax effects resulting from the new income tax rates. The Company applied the amendments as of January 1, 2018 by reclassifying $3.0 million from AOCL to retained earnings, eliminating the stranded tax effects in AOCL resulting from the TCJA. This reclassification reduced AOCL and increased retained earnings by $3.0 million. It is the Company's policy to release income tax effects from AOCI/AOCL using the item-by-item approach.

On January 1, 2018, the Company adopted ASU 2014-09, Revenue from Contracts with Customers, which supersedes previous revenue guidance. The standard requires that the Company recognize revenue when it transfers the promised goods or services to customers in an amount that reflects the consideration the Company expects to receive in exchange for those goods or services. The Company adopted ASU 2014-09 and all related amendments using the modified retrospective approach. Under the standard, the Company continues to recognize freight revenue proportionally as a shipment moves from origin to destination. The adoption did not affect the Company’s financial condition, results of operations or liquidity. Disclosures related to the nature, amount and timing of revenue and cash flows resulting from contracts with customers are included in Note 4, Revenue.

On December 1, 2016, a subsidiary of the Company completed the acquisition of Glencore Rail (NSW) Pty Limited (GRail) and concurrently issued a 48.9% stake in G&W Australia Holdings LP (GWAHLP) (collectively, the Australia Partnership), which is the holding entity for all of the Company’s Australian businesses, including GRail, to a consortium of funds and clients managed by Macquarie Infrastructure and Real Assets (MIRA), a large infrastructure investment firm. The Company, through wholly-owned subsidiaries, also made incremental investments and retained a 51.1% ownership in GWAHLP. The investments made by both the Company and MIRA consisted of equity and debt financing of GWAHLP in similar proportions. As MIRA's investments were made at the contemporaneous fair value of GWAHLP as of December 1, 2016, accounting for MIRA's noncontrolling interest in the Company's consolidated financial statements required adjustments to reflect a proportional interest in the net book value of GWAHLP. During the three months ended March 31, 2018, the Company determined that there was an error in its December 1, 2016 calculation of the noncontrolling interest for MIRA's 48.9% equity interest, which resulted in the following adjustment within the total equity section of the Company's consolidated balance sheet: a decrease in noncontrolling interest of $71.9 million, an increase in additional paid-in capital of $57.9 million and a decrease in AOCL of $14.0 million. This revision has been reflected in the Company's consolidated balance sheet as of December 31, 2017 as well as the December 31, 2016 equity balances as disclosed in the Company's consolidated statements of changes in equity. There was no effect on any other section of the Company's balance sheet. This revision had no impact on the Company's consolidated statements of operations, comprehensive income or cash flows for the three and nine months ended September 30, 2018 and 2017. The Company does not consider this revision material to any previously issued consolidated financial statements.

When comparing the Company's results of operations from one reporting period to another, it is important to consider that the Company has historically experienced fluctuations in revenues and expenses due to acquisitions, changing economic conditions, fluctuations in commodity prices, competitive forces, changes in foreign currency exchange rates, rail network issues and congestion, the ability to attract and retain skilled workers, one-time freight moves, fuel price fluctuations, customer plant expansions and shutdowns, sales of property and equipment, derailments and weather-related conditions, such as hurricanes, cyclones, tornadoes, high winds, droughts, heavy snowfall, unseasonably hot or cold weather, freezing and flooding, among other factors. In periods when these events occur, the Company's results of operations are not easily comparable from one period to another. Finally, certain of the Company's railroads have commodity shipments that are sensitive to general economic conditions, global commodity prices and foreign exchange rates, such as steel products, iron ore, paper products, lumber and forest products and agricultural products, as well as product specific market conditions, such as the availability of lower priced alternative sources of power generation (coal) and energy commodity price differentials (crude oil and natural gas liquids) or congestion at ports (intermodal). Other shipments are relatively less affected by economic conditions and are more closely affected by other factors, such as winter weather (salt) and seasonal rainfall (agricultural products). As a result of these and other factors, the Company's results of operations in any reporting period may not be directly comparable to the Company's results of operations in other reporting periods.