Background and Basis of Presentation	6 Months Ended
Background and Basis of Presentation	Jun. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Background and Basis of Presentation	Background and Basis of Presentation Terra Nitrogen Company, L.P. ("TNCLP," "we," "our" or "us") is a Delaware limited partnership that produces nitrogen fertilizer products. Our principal products are anhydrous ammonia (ammonia) and urea ammonium nitrate solution (UAN), which we manufacture at our facility in Verdigris, Oklahoma. We conduct our operations through an operating partnership, Terra Nitrogen, Limited Partnership (TNLP or the Operating Partnership, and collectively with TNCLP, the Partnership). Terra Nitrogen GP Inc. (TNGP or the General Partner), a Delaware corporation, is the general partner of both TNCLP and TNLP and owns a 0.025% general partner interest in each of TNCLP and TNLP. The General Partner is an indirect, wholly owned subsidiary of CF Industries Holdings, Inc. (CF Industries), a Delaware corporation. Ownership of TNCLP is composed of the general partner interests and the limited partner interests. The general partner interest in TNCLP is represented by 4,720 general partner units. Limited partner interests are represented by common units, which are listed for trading on the New York Stock Exchange under the symbol "TNH," and Class B common units. As of June 30, 2017, we had 18,501,576 common units and 184,072 Class B common units issued and outstanding. CF Industries through its subsidiaries owned 13,889,014 common units (representing approximately 75.1% of the total outstanding common units) and all of the Class B common units as of June 30, 2017. We are a master limited partnership (MLP). Partnerships are generally not subject to federal income tax, although publicly traded partnerships (such as TNCLP) are treated as corporations for federal income tax purposes (and therefore are subject to federal income tax), unless at least 90% of the partnership's gross income is "qualifying income" as defined in Section 7704 of the Internal Revenue Code of 1986, as amended, and the partnership is not required to register as an investment company under the Investment Company Act of 1940. As we currently satisfy the requirements to be treated as a partnership for federal income tax purposes, no federal income taxes are paid by the Partnership. On January 19, 2017, the Internal Revenue Service (IRS) issued final regulations on the types of income and activities that constitute or generate qualifying income of a MLP. For calendar year MLPs, the effective date of the regulations is January 1, 2018. The regulations have the effect of limiting the types of income and activities that qualify under the MLP rules, subject to certain transition provisions. The regulations define the activities that generate qualifying income from certain processing or refining and transportation activities with respect to any mineral or natural resource (including fertilizer) as activities that generate qualifying income, but the regulations reserve on specifics regarding fertilizer-related activities. However, the IRS has issued a private letter ruling to a taxpayer in the fertilizer industry unrelated to TNCLP which would indicate that each taxpayer's fertilizer manufacturing activities should produce qualifying income for purposes of determining whether 90% of the partnership's gross income is qualifying income. The entity to which this private letter ruling was issued would appear to operate a nitrogen fertilizer manufacturing business that is similar to ours. While this private letter ruling provides some insight into the manner in which the IRS analyzed fertilizer manufacturing activities at the time this ruling was issued, this private letter ruling is specific to a different entity. Thus, the IRS is not bound to follow it in respect of TNCLP, nor may we rely on it as precedent when determining whether we satisfy the MLP 90% gross income test. Any change in the federal income tax treatment of income from fertilizer-related activities as qualifying income could have a material impact on the taxation of the Partnership and could have a material adverse impact on unitholder distributions. We continue to monitor these IRS regulatory activities. The accompanying unaudited interim consolidated financial statements have been prepared on the same basis as our audited consolidated financial statements for the year ended December 31, 2016, in accordance with accounting principles generally accepted in the United States (U.S. GAAP) for interim financial reporting. In the opinion of management, these statements reflect all adjustments, consisting only of normal and recurring adjustments, that are necessary for the fair representation of the information for the periods presented. The unaudited interim consolidated financial statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (SEC). Certain information and footnote disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles have been condensed or omitted pursuant to such rules and regulations. Operating results for any period presented apply to that period only and are not necessarily indicative of results for any future period. The preparation of the unaudited interim consolidated financial statements requires management to make use of estimates and assumptions that affect the reported amount of assets and liabilities, revenue and expenses and certain financial statement disclosures. Actual results could differ from these estimates. Significant estimates and assumptions in these unaudited interim consolidated financial statements include net realizable value of inventories, environmental remediation liabilities, environmental and litigation contingencies, useful lives of property, plant and equipment, the assumptions used in the evaluation of potential impairments of property, plant and equipment and the allowance for doubtful accounts receivable. The accompanying unaudited interim consolidated financial statements should be read in conjunction with our audited consolidated financial statements and related disclosures included in our 2016 Annual Report on Form 10-K filed with the SEC on February 23, 2017. Throughout this document, the term "affiliates of the General Partner" refers to consolidated subsidiaries of CF Industries, including TNGP.

TERRA NITROGEN CO L P /DE 10-Q