Basis of Presentation and Significant Accounting Policies	9 Months Ended
Sep. 30, 2018
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	Basis of Presentation and Significant Accounting Policies World Fuel Services Corporation (the “Company”) was incorporated in Florida in July 1984 and along with its consolidated subsidiaries is referred to collectively in this Quarterly Report on Form 10‑Q ("10-Q Report") as “World Fuel,” “we,” “our” and “us.” We are a leading global fuel services company, principally engaged in the distribution of fuel and related products and services in the aviation, marine and land transportation industries. We have expanded our product and service offerings to include energy advisory services and supply fulfillment with respect to natural gas and power and transaction and payment management solutions to commercial and industrial customers. Our intention is to become a leading global energy management company offering a full suite of energy advisory, management and fulfillment services and technology solutions across the energy product spectrum. We also seek to become a leading transaction and payment management company, offering payment management solutions to commercial and industrial customers, principally in the aviation, land and marine transportation industries. We prepared the consolidated financial statements following the requirements of the United States (“U.S.”) Securities and Exchange Commission (“SEC”) for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by accounting principles generally accepted in the U.S. (“U.S. GAAP”) can be condensed or omitted. Revenues, expenses, assets and liabilities can vary during each quarter of the year. Therefore, the results and trends in these interim financial statements may not be representative of those for the full year. In our opinion, all adjustments necessary for a fair statement of the financial statements, which are of a normal and recurring nature, have been made for the interim periods reported. The information included in this 10-Q Report should be read in conjunction with the consolidated financial statements and accompanying notes included in our 2017 Annual Report on Form 10-K (“2017 10-K Report”). Certain amounts in the consolidated financial statements and associated notes may not add due to rounding. All percentages have been calculated using unrounded amounts. There have been no significant changes, other than those related to the adopted new accounting standards below, in the Company's accounting policies from those disclosed in our 2017 10‑K Report. The significant accounting policies we use for quarterly financial reporting are disclosed in Note 1 of the “Notes to the Consolidated Financial Statements” included in our 2017 10‑K Report, and in the adopted accounting standards below. Adoption of New Accounting Standard Revenue Recognition (Topic 606): Revenue from Contracts with Customers. In May 2014, ASU 2014-09 was issued. Under this ASU and subsequently issued amendments, we recognize the amount of revenue when delivery is made and our customer obtains control, and we are entitled to compensation for performance completed. The updated standard replaced most existing revenue recognition guidance in U.S. GAAP. We adopted this standard as of January 1, 2018 using the modified retrospective adoption approach, and elected to apply it only to those contracts that were not considered completed contracts as of this adoption date. This approach required us to recognize the cumulative effect of initially applying the new standard as an adjustment to the opening balance of retained earnings. This cumulative adjustment did not have a material impact on our financial statements. Income Statement - Reporting Comprehensive Income (Topic 220). In February 2018, ASU 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, was issued. ASU 2018-02 provides the option to reclassify stranded tax effects within AOCI to retained earnings in each period in which the effect of the change in the U.S. federal corporate tax rate in the U.S. Tax Cuts and Jobs Act ("Tax Reform Act") is recorded. ASU 2018-02 is effective for fiscal years beginning after December 15, 2018, and interim periods within those years. Early adoption is permitted. This updated standard allows for adoption in the period of adoption or retrospectively to each period in which the effect of the change in the U.S. federal corporate income tax rate in the Tax Reform Act is recognized. We adopted this updated standard in the first quarter of 2018, and subsequently reclassified the tax rate disparity to retained earnings. Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40). In August 2018, ASU 2018-15, Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract, was issued. The ASU aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The standard also requires the entity (customer) to expense the capitalized implementation costs over the term of the hosting arrangement. We early adopted this updated standard, which did not have a material impact on our consolidated financial statements. Income Taxes (Topic 740). In March 2018, ASU 2018-05, Amendments to SEC Paragraphs Pursuant to SEC Staff Accounting Bulletin No. 118, was issued. ASU 2018-05 amends certain SEC material in Topic 740 for the income tax accounting implications of the recently issued U.S. Tax Cuts and Jobs Act ("Tax Reform Act"). We have adopted these amendments and where the accounting under Topic 740 is incomplete for certain specific income tax effects of the Tax Reform Act, we reported provisional amounts. Business Combinations (Topic 805): Clarifying the Definition of a Business. In January 2017, ASU 2017-01 was issued. The update clarifies the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of businesses after adoption. This standard was effective at the beginning of our 2018 fiscal year and did not have a material impact on our consolidated financial statements and disclosures. Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities. In August 2017, ASU 2017-12 was issued. The ASU is targeted at simplifying hedge accounting requirements, creating more transparency around how economic results are presented and disclosed on the consolidated financial statements and accompanying footnote disclosures. We early adopted this updated standard, which did not have a material impact on our consolidated financial statements. We have provided updated disclosures in Note 3. Derivatives. Cash Flows: Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments. In August 2016, ASU 2016-15 was issued. The ASU provides guidance on classification of eight specific cash flows items. This standard is effective at the beginning of our 2018 fiscal year and we have provided an updated line item attributable to retained beneficial interests associated with our receivables purchase agreements on our consolidated statements of cash flows. The adoption resulted in a $236.3 million retrospective reclassification of the beneficial interest received in exchange for accounts receivable sales for the nine months ended September 30, 2017 from cash flows from operating activities to cash flows from investing activities. Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other than Inventory. In October 2016, ASU 2016-16 was issued. The update prohibits the recognition of current and deferred income taxes for an intra-entity asset transfer until the asset has been sold to an outside party. This standard is effective at the beginning of our 2018 fiscal year. The adoption of this ASU did not have a material impact on our consolidated financial statements and disclosures. Cash Flows: Statement of Cash Flows (Topic 230): Restricted Cash. In November 2016, ASU 2016-18 was issued. The update requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash or restricted cash equivalents. This standard is effective at the beginning of our 2018 fiscal year. The adoption of this ASU did not have a material impact on our consolidated financial statements and disclosures. Accounting Standards Issued but Not Yet Adopted Leases (Topic 842). In February 2016, ASU 2016-02, Leases, was issued. The new standard requires lessors to account for leases using an approach that is substantially equivalent to existing guidance for direct financing and operating leases. Upon adoption, this standard will require all lessees to recognize a right of use asset and a liability to make lease payments (lease liability) on the balance sheet, except for leases with durations of twelve months or less. Lessees (for capital and operating leases) must apply a modified retrospective transition approach for leases existing at or after the beginning of the earliest comparative period presented in the consolidated financial statements. The modified retrospective approach would not require any transition accounting for leases that expired before the earliest comparative period presented. This standard is effective at the beginning of our 2019 fiscal year. In preparation for adoption of the standard, we developed a cross-functional team and engaged a third-party service provider to assist us throughout our evaluation, including the selection of a lease software and contract administration platform. We continue to evaluate the overall impact the adoption of this new guidance will have on our consolidated financial statements and related disclosures.

World Fuel Services Corporation (the “Company”) was incorporated in Florida in July 1984 and along with its consolidated subsidiaries is referred to collectively in this Quarterly Report on Form 10‑Q ("10-Q Report") as “World Fuel,” “we,” “our” and “us.”

We are a leading global fuel services company, principally engaged in the distribution of fuel and related products and services in the aviation, marine and land transportation industries. We have expanded our product and service offerings to include energy advisory services and supply fulfillment with respect to natural gas and power and transaction and payment management solutions to commercial and industrial customers. Our intention is to become a leading global energy management company offering a full suite of energy advisory, management and fulfillment services and technology solutions across the energy product spectrum. We also seek to become a leading transaction and payment management company, offering payment management solutions to commercial and industrial customers, principally in the aviation, land and marine transportation industries.

We prepared the consolidated financial statements following the requirements of the United States (“U.S.”) Securities and Exchange Commission (“SEC”) for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by accounting principles generally accepted in the U.S. (“U.S. GAAP”) can be condensed or omitted.

Revenues, expenses, assets and liabilities can vary during each quarter of the year. Therefore, the results and trends in these interim financial statements may not be representative of those for the full year. In our opinion, all adjustments necessary for a fair statement of the financial statements, which are of a normal and recurring nature, have been made for the interim periods reported. The information included in this 10-Q Report should be read in conjunction with the consolidated financial statements and accompanying notes included in our 2017 Annual Report on Form 10-K (“2017 10-K Report”). Certain amounts in the consolidated financial statements and associated notes may not add due to rounding. All percentages have been calculated using unrounded amounts.

There have been no significant changes, other than those related to the adopted new accounting standards below, in the Company's accounting policies from those disclosed in our 2017 10‑K Report. The significant accounting policies we use for quarterly financial reporting are disclosed in Note 1 of the “Notes to the Consolidated Financial Statements” included in our 2017 10‑K Report, and in the adopted accounting standards below.

Revenue Recognition (Topic 606): Revenue from Contracts with Customers. In May 2014, ASU 2014-09 was issued. Under this ASU and subsequently issued amendments, we recognize the amount of revenue when delivery is made and our customer obtains control, and we are entitled to compensation for performance completed. The updated standard replaced most existing revenue recognition guidance in U.S. GAAP. We adopted this standard as of January 1, 2018 using the modified retrospective adoption approach, and elected to apply it only to those contracts that were not considered completed contracts as of this adoption date. This approach required us to recognize the cumulative effect of initially applying the new standard as an adjustment to the opening balance of retained earnings. This cumulative adjustment did not have a material impact on our financial statements.

Income Statement - Reporting Comprehensive Income (Topic 220). In February 2018, ASU 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, was issued. ASU 2018-02 provides the option to reclassify stranded tax effects within AOCI to retained earnings in each period in which the effect of the change in the U.S. federal corporate tax rate in the U.S. Tax Cuts and Jobs Act ("Tax Reform Act") is recorded. ASU 2018-02 is effective for fiscal years beginning after December 15, 2018, and interim periods within those years. Early adoption is permitted. This updated standard allows for adoption in the period of adoption or retrospectively to each period in which the effect of the change in the U.S. federal corporate income tax rate in the Tax Reform Act is recognized. We adopted this updated standard in the first quarter of 2018, and subsequently reclassified the tax rate disparity to retained earnings.

Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40). In August 2018, ASU 2018-15, Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract, was issued. The ASU aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The standard also requires the entity (customer) to expense the

capitalized implementation costs over the term of the hosting arrangement. We early adopted this updated standard, which did not have a material impact on our consolidated financial statements.

Income Taxes (Topic 740). In March 2018, ASU 2018-05, Amendments to SEC Paragraphs Pursuant to SEC Staff Accounting Bulletin No. 118, was issued. ASU 2018-05 amends certain SEC material in Topic 740 for the income tax accounting implications of the recently issued U.S. Tax Cuts and Jobs Act ("Tax Reform Act"). We have adopted these amendments and where the accounting under Topic 740 is incomplete for certain specific income tax effects of the Tax Reform Act, we reported provisional amounts.

Business Combinations (Topic 805): Clarifying the Definition of a Business. In January 2017, ASU 2017-01 was issued. The update clarifies the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of businesses after adoption. This standard was effective at the beginning of our 2018 fiscal year and did not have a material impact on our consolidated financial statements and disclosures.

Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities. In August 2017, ASU 2017-12 was issued. The ASU is targeted at simplifying hedge accounting requirements, creating more transparency around how economic results are presented and disclosed on the consolidated financial statements and accompanying footnote disclosures. We early adopted this updated standard, which did not have a material impact on our consolidated financial statements. We have provided updated disclosures in Note 3. Derivatives.

Cash Flows: Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments. In August 2016, ASU 2016-15 was issued. The ASU provides guidance on classification of eight specific cash flows items. This standard is effective at the beginning of our 2018 fiscal year and we have provided an updated line item attributable to retained beneficial interests associated with our receivables purchase agreements on our consolidated statements of cash flows. The adoption resulted in a $236.3 million retrospective reclassification of the beneficial interest received in exchange for accounts receivable sales for the nine months ended September 30, 2017 from cash flows from operating activities to cash flows from investing activities.

Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other than Inventory. In October 2016, ASU 2016-16 was issued. The update prohibits the recognition of current and deferred income taxes for an intra-entity asset transfer until the asset has been sold to an outside party. This standard is effective at the beginning of our 2018 fiscal year. The adoption of this ASU did not have a material impact on our consolidated financial statements and disclosures.

Cash Flows: Statement of Cash Flows (Topic 230): Restricted Cash. In November 2016, ASU 2016-18 was issued. The update requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash or restricted cash equivalents. This standard is effective at the beginning of our 2018 fiscal year. The adoption of this ASU did not have a material impact on our consolidated financial statements and disclosures.