Overview	6 Months Ended
Jun. 30, 2016
Overview [Abstract]
OVERVIEW	OVERVIEW SemGroup Corporation is a Delaware corporation headquartered in Tulsa, Oklahoma. The terms "we," "our," "us," "SemGroup," "the Company" and similar language used in these notes to the unaudited condensed consolidated financial statements refer to SemGroup Corporation and its subsidiaries. Basis of presentation The accompanying condensed consolidated balance sheet at December 31, 2015, which is derived from audited financial statements, and the unaudited condensed consolidated interim financial statements have been prepared in accordance with accounting principles generally accepted in the United States and the rules and regulations of the Securities and Exchange Commission ("SEC"). These financial statements include all normal and recurring adjustments that, in the opinion of management, are necessary to present fairly the financial position of the Company and the results of its operations and its cash flows. Our condensed consolidated financial statements include the accounts of our controlled subsidiaries. All significant transactions between our consolidated subsidiaries have been eliminated. The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the amounts and disclosures in the financial statements. Although management believes these estimates are reasonable, actual results could differ materially from these estimates. The results of operations for the three months and six months ended June 30, 2016, are not necessarily indicative of the results to be expected for the full year ending December 31, 2016. Pursuant to the rules and regulations of the SEC, the accompanying condensed consolidated financial statements do not include all of the information and notes normally included with financial statements prepared in accordance with accounting principles generally accepted in the United States. Certain reclassifications have been made to conform previously reported balances to the current presentation. These condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2015, which are included in our Annual Report on Form 10-K for the year ended December 31, 2015, filed with the SEC. Our significant accounting policies are consistent with those described in our Annual Report on Form 10-K for the year ended December 31, 2015. Recent accounting pronouncements In June 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-13, "Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments", which introduces new guidance for estimating credit losses on certain types of financial instruments based on expected losses and the timing of the recognition of such losses. For public entities, this ASU is effective for annual periods beginning after December 15, 2019, and interim periods within those years and early adoption is permitted in the year prior to the effective date. We will adopt this guidance in the first quarter of 2020. The impact is not expected to be material. In March 2016, the FASB issued ASU 2016-09, "Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting'', which simplifies several aspects of the accounting for employee share-based payment transactions, including the accounting for income taxes, forfeitures and statutory tax withholding requirements, as well as classification in the statement of cash flows. For public entities, this ASU is effective for annual periods beginning after December 15, 2016, and interim periods within those years and early adoption is permitted. We will adopt this guidance in the first quarter of 2017. The impact is not expected to be material. In February 2016, the FASB issued ASU 2016-02, "Leases (Topic 842)", which amends the existing lease guidance to require lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by operating and finance leases and to disclose additional quantitative and qualitative information about leasing arrangements. This ASU also provides clarifications surrounding the presentation of the effects of leases in the income statement and statement of cash flows. For public entities, this ASU will be effective for annual periods beginning after December 15, 2018, and interim periods within those years. The new guidance shall be applied using a modified retrospective approach and early adoption is permitted. We are currently evaluating the impact of the adoption of ASU 2016-02 on our consolidated financial statements. We will adopt this guidance in the first quarter of 2019. In November 2015, the FASB issued ASU 2015-17, "Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes", which requires all deferred tax assets and liabilities to be classified as noncurrent in the statement of financial position. For public entities, this ASU is effective for annual periods beginning after December 15, 2016, and interim periods within those years. The new guidance may be applied prospectively or retrospectively and early adoption is permitted. We have not determined which method we will apply when we adopt the standard. We will adopt this guidance in the first quarter of 2017. The impact is not expected to be material. In July 2015, the FASB issued ASU 2015-11, "Inventory (Topic 330): Simplifying the Measurement of Inventory", which requires that inventory within the scope of the guidance be measured at the lower of cost and net realizable value rather than the lower of cost or market. The standard will be effective for public business entities for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. The new guidance shall be applied prospectively and early adoption is permitted. We will adopt this guidance in the first quarter of 2017. The impact is not expected to be material. In April 2015, the FASB issued ASU 2015-03, “Interest - Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs”, which is designed to simplify presentation of debt issuance costs. The standard requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. In August 2015, the FASB issued ASU 2015-15, “Interest - Imputation of Interest (Subtopic 835-30): Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements - Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EITF Meeting,” which amended the SEC paragraphs of ASC Subtopic 835-30 to include the language from the SEC Staff Announcement indicating that the SEC would not object to presenting deferred debt issuance costs related to line-of-credit agreements as assets and subsequently amortizing the deferred debt issuance costs ratably over the term of the agreement. The standards are effective for U.S. public companies for annual reporting periods beginning after December 15, 2015. The new guidance has been applied on a retrospective basis for all periods presented. We adopted this guidance in the first quarter of 2016. The impact was not material. For presentation purposes, $16.8 million of debt issuance costs which had previously been reported as other noncurrent assets were reclassified as a reduction of long-term debt on the December 31, 2015 balance sheet. Capitalized loan fees related to our revolving credit facilities continue to be presented as other noncurrent assets. In February 2015, the FASB issued ASU 2015-02, “Consolidation (Topic 810): Amendments to the Consolidation Analysis,” which adds requirements that limited partnerships must meet to qualify as voting interest entities and modifies the evaluation of whether limited partnerships are variable interest entities or voting interest entities. It also eliminates the presumption that a general partner should consolidate a limited partnership. This guidance is effective for public companies for fiscal years beginning after December 15, 2015. We adopted this guidance in the first quarter of 2016. The impact was not material. In May 2014, the FASB issued ASU 2014-09, "Revenue from Contracts with Customers," which supersedes nearly all existing revenue recognition guidance under accounting principles generally accepted in the United States ("U.S. GAAP"). The core principle of ASU 2014-09 is to recognize revenues when promised goods or services are transferred to customers in an amount that reflects the consideration to which an entity expects to be entitled for those goods or services. ASU 2014-09 defines a five step process to achieve this core principle and, in doing so, more judgment and estimates may be required within the revenue recognition process than are required under existing U.S. GAAP. The standard permits using either of the following transition methods: (i) a full retrospective approach reflecting the application of the standard in each prior reporting period with the option to elect certain practical expedients, or (ii) a retrospective approach with the cumulative effect of initially adopting ASU 2014-09 recognized at the date of adoption (which includes additional footnote disclosures). In August 2015, the FASB issued ASU 2015-14 which deferred the effective date of ASU 2014-09 by one year. In March 2016, the FASB issued ASU 2016-08 which amended the principal-versus-agent implementation guidance set forth in ASU 2014-09. Among other things, ASU 2016-08 clarifies that an entity should evaluate whether it is the principal or the agent for each specified good or service promised in a contract with a customer. In April 2016, the FASB issued ASU 2016-10 which amended certain aspects of the guidance related to identifying performance obligations and licensing implementation within ASU 2014-09. In June 2016, the FASB issued ASU 2016-12 which narrows the scope around certain aspects of the criterion used in determining when to recognize revenue. We are currently evaluating the impact of our pending adoption of ASU 2014-09 on our consolidated financial statements and have not yet determined the method by which we will adopt the standard. We will adopt this guidance in the first quarter of 2018.

OVERVIEW

SemGroup Corporation is a Delaware corporation headquartered in Tulsa, Oklahoma. The terms "we," "our," "us," "SemGroup," "the Company" and similar language used in these notes to the unaudited condensed consolidated financial statements refer to SemGroup Corporation and its subsidiaries.

Basis of presentation

The accompanying condensed consolidated balance sheet at December 31, 2015, which is derived from audited financial statements, and the unaudited condensed consolidated interim financial statements have been prepared in accordance with accounting principles generally accepted in the United States and the rules and regulations of the Securities and Exchange Commission ("SEC"). These financial statements include all normal and recurring adjustments that, in the opinion of management, are necessary to present fairly the financial position of the Company and the results of its operations and its cash flows.

Our condensed consolidated financial statements include the accounts of our controlled subsidiaries. All significant transactions between our consolidated subsidiaries have been eliminated.

The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the amounts and disclosures in the financial statements. Although management believes these estimates are reasonable, actual results could differ materially from these estimates. The results of operations for the three months and six months ended June 30, 2016, are not necessarily indicative of the results to be expected for the full year ending December 31, 2016.

Pursuant to the rules and regulations of the SEC, the accompanying condensed consolidated financial statements do not include all of the information and notes normally included with financial statements prepared in accordance with accounting principles generally accepted in the United States. Certain reclassifications have been made to conform previously reported balances to the current presentation. These condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2015, which are included in our Annual Report on Form 10-K for the year ended December 31, 2015, filed with the SEC.

Our significant accounting policies are consistent with those described in our Annual Report on Form 10-K for the year ended December 31, 2015.

Recent accounting pronouncements

In June 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-13, "Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments", which introduces new guidance for estimating credit losses on certain types of financial instruments based on expected losses and the timing of the recognition of such losses. For public entities, this ASU is effective for annual periods beginning after December 15, 2019, and interim periods within those years and early adoption is permitted in the year prior to the effective date. We will adopt this guidance in the first quarter of 2020. The impact is not expected to be material.

In March 2016, the FASB issued ASU 2016-09, "Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting'', which simplifies several aspects of the accounting for employee share-based payment transactions, including the accounting for income taxes, forfeitures and statutory tax withholding requirements, as well as classification in the statement of cash flows. For public entities, this ASU is effective for annual periods beginning after December 15, 2016, and interim periods within those years and early adoption is permitted. We will adopt this guidance in the first quarter of 2017. The impact is not expected to be material.

In February 2016, the FASB issued ASU 2016-02, "Leases (Topic 842)", which amends the existing lease guidance to require lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by operating and finance leases and to disclose additional quantitative and qualitative information about leasing arrangements. This ASU also provides clarifications surrounding the presentation of the effects of leases in the income statement and statement of cash flows. For public entities, this ASU will be effective for annual periods beginning after December 15, 2018, and interim periods within those years. The new guidance shall be applied using a modified retrospective approach and early adoption is permitted. We are currently evaluating the impact of the adoption of ASU 2016-02 on our consolidated financial statements. We will adopt this guidance in the first quarter of 2019.

In November 2015, the FASB issued ASU 2015-17, "Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes", which requires all deferred tax assets and liabilities to be classified as noncurrent in the statement of financial position. For public entities, this ASU is effective for annual periods beginning after December 15, 2016, and interim periods within those years. The new guidance may be applied prospectively or retrospectively and early adoption is permitted. We have not determined which method we will apply when we adopt the standard. We will adopt this guidance in the first quarter of 2017. The impact is not expected to be material.

In July 2015, the FASB issued ASU 2015-11, "Inventory (Topic 330): Simplifying the Measurement of Inventory", which requires that inventory within the scope of the guidance be measured at the lower of cost and net realizable value rather than the lower of cost or market. The standard will be effective for public business entities for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. The new guidance shall be applied prospectively and early adoption is permitted. We will adopt this guidance in the first quarter of 2017. The impact is not expected to be material.

In April 2015, the FASB issued ASU 2015-03, “Interest - Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs”, which is designed to simplify presentation of debt issuance costs. The standard requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. In August 2015, the FASB issued ASU 2015-15, “Interest - Imputation of Interest (Subtopic 835-30): Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements - Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EITF Meeting,” which amended the SEC paragraphs of ASC Subtopic 835-30 to include the language from the SEC Staff Announcement indicating that the SEC would not object to presenting deferred debt issuance costs related to line-of-credit agreements as assets and subsequently amortizing the deferred debt issuance costs ratably over the term of the agreement. The standards are effective for U.S. public companies for annual reporting periods beginning after December 15, 2015. The new guidance has been applied on a retrospective basis for all periods presented. We adopted this guidance in the first quarter of 2016. The impact was not material. For presentation purposes, $16.8 million of debt issuance costs which had previously been reported as other noncurrent assets were reclassified as a reduction of long-term debt on the December 31, 2015 balance sheet. Capitalized loan fees related to our revolving credit facilities continue to be presented as other noncurrent assets.

In February 2015, the FASB issued ASU 2015-02, “Consolidation (Topic 810): Amendments to the Consolidation Analysis,” which adds requirements that limited partnerships must meet to qualify as voting interest entities and modifies the evaluation of whether limited partnerships are variable interest entities or voting interest entities. It also eliminates the presumption that a general partner should consolidate a limited partnership. This guidance is effective for public companies for fiscal years beginning after December 15, 2015. We adopted this guidance in the first quarter of 2016. The impact was not material.

In May 2014, the FASB issued ASU 2014-09, "Revenue from Contracts with Customers," which supersedes nearly all existing revenue recognition guidance under accounting principles generally accepted in the United States ("U.S. GAAP"). The core principle of ASU 2014-09 is to recognize revenues when promised goods or services are transferred to customers in an amount that reflects the consideration to which an entity expects to be entitled for those goods or services. ASU 2014-09 defines a five step process to achieve this core principle and, in doing so, more judgment and estimates may be required within the revenue recognition process than are required under existing U.S. GAAP. The standard permits using either of the following transition methods: (i) a full retrospective approach reflecting the application of the standard in each prior reporting period with the option to elect certain practical expedients, or (ii) a retrospective approach with the cumulative effect of initially adopting ASU 2014-09 recognized at the date of adoption (which includes additional footnote disclosures). In August 2015, the FASB issued ASU 2015-14 which deferred the effective date of ASU 2014-09 by one year. In March 2016, the FASB issued ASU 2016-08 which amended the principal-versus-agent implementation guidance set forth in ASU 2014-09. Among other things, ASU 2016-08 clarifies that an entity should evaluate whether it is the principal or the agent for each specified good or service promised in a contract with a customer. In April 2016, the FASB issued ASU 2016-10 which amended certain aspects of the guidance related to identifying performance obligations and licensing implementation within ASU 2014-09. In June 2016, the FASB issued ASU 2016-12 which narrows the scope around certain aspects of the criterion used in determining when to recognize revenue. We are currently evaluating the impact of our pending adoption of ASU 2014-09 on our consolidated financial statements and have not yet determined the method by which we will adopt the standard. We will adopt this guidance in the first quarter of 2018.