Sisecam Resources (SIRE) 10-Q 11 May 20 2020 Q1 Quarterly report Financial data

DOCUMENT AND ENTITY INFORMATION

DOCUMENT AND ENTITY INFORMATION - shares	3 Months Ended
	Mar. 31, 2020	May 04, 2020
Document Information [Line Items]
Entity Registrant Name	Ciner Resources LP
Entity Central Index Key	0001575051
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus (Q1,Q2,Q3,FY)	Q1
Amendment Flag	false
Emerging Growth Company	false
Small Business Entity	false
Entity Current Reporting Status	Yes
Entity Shell Company	false
Common Unitholders
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		19,767,335
General Partner
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		399,000

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 51.4	$ 14.9
Accounts receivable—affiliates	86.2	95
Accounts receivable, net	44.6	36
Inventory	31	24.2
Other current assets	1.5	2.2
Total current assets	214.7	172.3
Property, plant and equipment, net	302.7	297.7
Other non-current assets	23	24.3
Total assets	540.4	494.3
Current liabilities:
Current portion of long-term debt	2.9	0
Accounts payable	19.4	14.2
Due to affiliates	2	3
Accrued expenses	34.2	39.1
Total current liabilities	58.5	56.3
Long-term debt	173.4	129.5
Other non-current liabilities	10.3	8.6
Total liabilities	242.2	194.4
Commitments and contingencies (See Note 9)
Equity:
Common unitholders - Public and Ciner Holdings (19.7 and 19.8 units issued and outstanding at March 31, 2020 and December 31, 2019)	171.4	171.4
General partner unitholders - Ciner Resource Partners LLC (0.4 units issued and outstanding at March 31, 2020 and December 31, 2019)	4.3	4.3
Accumulated other comprehensive loss	(4)	(3)
Partners’ capital attributable to Ciner Resources LP	171.7	172.7
Non-controlling interest	126.5	127.2
Total equity	298.2	299.9
Total liabilities and partners’ equity	$ 540.4	$ 494.3

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - shares shares in Millions	Mar. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Common units issued (in shares)	19.7	19.8
Common units outstanding (in shares)	19.7	19.8
General partner units issued (in shares)	0.4	0.4
General partner units outstanding (in shares)	0.4	0.4

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Net Sales:
Sales—affiliates	$ 54	$ 77.5
Sales—others	60.4	52.9
Net sales	114.4	130.4
Operating costs and expenses:
Cost of products sold including freight costs (excludes depreciation, depletion and amortization expense set forth separately below)	86.6	90.2
Depreciation, depletion and amortization expense	6.5	6.3
Selling, general and administrative expenses—affiliates	4.1	5.5
Selling, general and administrative expenses—others	1.7	1.9
Total operating costs and expenses	98.9	103.9
Operating income	15.5	26.5
Other income (expenses):
Interest income	0	0.1
Interest expense	(1.3)	(1.4)
Total other expense, net	(1.3)	(1.3)
Net income	14.2	25.2
Net income attributable to non-controlling interest	7.5	12.9
Net income attributable to Ciner Resources LP	6.7	12.3
Other comprehensive loss:
(Loss)/income on derivative financial instruments	(2.1)	2
Comprehensive income	12.1	27.2
Comprehensive income attributable to non-controlling interest	6.4	13.9
Comprehensive income attributable to Ciner Resources LP	$ 5.7	$ 13.3
Net income per limited partner unit:
Net income per limited partner unit - basic and diluted (in dollars per share)	$ 0.34	$ 0.61
Limited partner units outstanding:
Weighted average limited partner units outstanding - basic and diluted (in shares)	19.7	19.7

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2013
Cash flows from operating activities:
Net income	$ 14.2	$ 25.2
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization expense	6.5	6.3
Equity-based compensation expenses	0.4	0.4
Other non-cash items	0	(0.1)
Changes in operating assets and liabilities:
Accounts receivable—affiliates	8.8	(22.4)
Accounts receivable, net	(8.6)	(4.5)
Inventory	(5.5)	(2.1)
Other current and non current assets	0.7	0.4
Increase (decrease) in:
Accounts payable	4.4	2.2
Due to affiliates	(0.9)	1.7
Accrued expenses and other liabilities	(3.3)	(1.5)
Net cash provided by operating activities	16.7	5.6
Cash flows from investing activities:
Capital expenditures	(12.9)	(24.7)
Net cash used in investing activities	(12.9)	(24.7)
Cash flows from financing activities:
Borrowings on Ciner Wyoming Credit Facility	76.5	60
Borrowings on Ciner Wyoming Equipment Financing Arrangement	30	0
Repayments on Ciner Wyoming Credit Facility	(59.5)	(12)
Debt issuance costs	(0.2)	0
Common units surrendered for taxes	(0.2)	(0.5)
Distributions to non-controlling interest	(7.1)	(9.8)
Net cash provided by financing activities	32.7	26.4
Net increase in cash and cash equivalents	36.5	7.3
Cash and cash equivalents at beginning of period	14.9	10.2
Cash and cash equivalents at end of period	51.4	17.5
Supplemental disclosure of cash flow information:
Interest paid during the period	1.3	1.2
Supplemental disclosure of non-cash investing activities:
Capital expenditures on account	5.6		$ 8
Common Unitholders
Cash flows from financing activities:
Distributions	(6.7)	(11.1)
General Partner
Cash flows from financing activities:
Distributions	$ (0.1)	$ (0.2)

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Millions	Total	Accumulated Other Comprehensive Loss	Partners’ Capital Attributable to Ciner Resources LP Equity	Non-controlling Interest	Common UnitholdersPartnership units	General PartnerPartnership units
Beginning balance at Dec. 31, 2018	$ 260.1	$ (3.8)	$ 153.9	$ 106.2	$ 153.8	$ 3.9
Increase (decrease) in shareholders' equity
Net income	25.2		12.3	12.9	12.1	0.2
Other comprehensive income/(loss)	2	1	1	1
Equity-based compensation plan activity	(0.3)		(0.3)		(0.3)
Distributions	(21.1)		(11.3)	(9.8)	(11.1)	(0.2)
Ending balance at Mar. 31, 2019	265.9	(2.8)	155.6	110.3	154.5	3.9
Beginning balance at Dec. 31, 2019	299.9	(3)	172.7	127.2	171.4	4.3
Increase (decrease) in shareholders' equity
Net income	14.2		6.7	7.5	6.6	0.1
Other comprehensive income/(loss)	(2.1)	(1)	(1)	(1.1)
Equity-based compensation plan activity	0.1		0.1		0.1
Distributions	(13.9)		(6.8)	(7.1)	(6.7)	(0.1)
Ending balance at Mar. 31, 2020	$ 298.2	$ (4)	$ 171.7	$ 126.5	$ 171.4	$ 4.3

CORPORATE STRUCTURE AND SUMMARY

CORPORATE STRUCTURE AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
CORPORATE STRUCTURE AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	CORPORATE STRUCTURE AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Nature of Operations The unaudited condensed consolidated financial statements are composed of Ciner Resources LP (the “Partnership,” “CINR,” “Ciner Resources,” “we,” “us,” or “our”), a publicly traded Delaware limited partnership, and its consolidated subsidiary, Ciner Wyoming LLC (“Ciner Wyoming”), which is in the business of mining trona ore to produce soda ash. The Partnership’s operations consist solely of its investment in Ciner Wyoming. The Partnership was formed in April 2013 by Ciner Wyoming Holding Co. (“Ciner Holdings”), a wholly-owned subsidiary of Ciner Resources Corporation (“Ciner Corp”). Ciner Corp is a direct wholly-owned subsidiary of Ciner Enterprises Inc. (“Ciner Enterprises”), which is a direct wholly-owned subsidiary of WE Soda Ltd., a U.K. corporation (“WE Soda”). WE Soda is a direct wholly-owned subsidiary of KEW Soda Ltd., a U.K. corporation (“KEW Soda”), which is a direct wholly-owned subsidiary of Akkan Enerji ve Madencilik Anonim Şirketi (“Akkan”). Akkan is directly and wholly owned by Turgay Ciner, the Chairman of the Ciner Group (“Ciner Group”), a Turkish conglomerate of companies engaged in energy and mining (including soda ash mining), media and shipping markets. The Partnership owns a controlling interest comprised of 51.0% membership interest in Ciner Wyoming. All of our soda ash processed is currently sold to various domestic and international customers, including ANSAC which is an affiliate for export sales. All mining and processing activities of Ciner Wyoming take place in one facility located in the Green River Basin of Wyoming. Basis of Presentation and Significant Accounting Policies The accompanying unaudited condensed consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles (“GAAP”) applicable to interim period financial statements and reflect all adjustments, consisting of normal recurring accruals, which are necessary for fair presentation of the results of operations, financial position and cash flows for the periods presented. All intercompany transactions, balances, revenue and expenses have been eliminated in consolidation. The results of operations for the three -month periods ended March 31, 2020 and 2019 are not necessarily indicative of the operating results for the full year. These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes to audited consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2019 (the “ 2019 Annual Report”) filed with the United States Securities and Exchange Commission on March 9, 2020. There have been no other material changes in the significant accounting policies followed by us during the three months ended March 31, 2020 from those disclosed in the 2019 Annual Report. Non-controlling interests NRP Trona LLC, a wholly-owned subsidiary of Natural Resource Partners L.P. ("NRP"), currently owns a 49.0% membership interest in Ciner Wyoming. NRP’s membership interest in Ciner Wyoming is reflected as the non-controlling interest in the Partnership’s financial results. Use of Estimates The preparation of these unaudited condensed consolidated financial statements, in accordance with GAAP, 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 dates of the unaudited condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Furthermore, we considered the impact of the COVID-19 pandemic on the use of estimates and assumptions used for financial reporting and determined that there was no adverse material impact to our results of operations for the first quarter of 2020. While our production is considered “essential”, the COVID-19 outbreak could also disrupt our customers and customer segments, which could have a negative impact on the demand for our products which could materially adversely affect our operations. As a result of these uncertainties, actual results could differ from those estimates and assumptions. If the economy or markets in which we operate remain weak or deteriorate further, our business, financial condition and results of operations may be materially and adversely impacted. Subsequent Events We have evaluated subsequent events through the filing date of this Quarterly Report on Form 10-Q. Recently Issued Accounting Pronouncements Recently Adopted Accounting Guidance In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-13, “Financial Instruments-Credit Losses (Topic 326)” (“ASU 2016-13”). This ASU introduces the current expected credit loss (CECL) model, which will require an entity to measure credit losses for certain financial instruments and financial assets, including trade receivables. Under this update, on initial recognition and at each reporting period, an entity will be required to recognize an allowance that reflects the entity’s current estimate of credit losses expected to be incurred over the life of the financial instrument. The Partnership adopted ASU 2016-13 effective January 1, 2020 and concluded there was no material impact to the Partnership’s condensed consolidated financial statements. In August 2018, the FASB issued ASU 2018-15, “Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (a consensus of the FASB Emerging Issues Task Force)” (“ASU 2018-15”), which amends Accounting Standards Codification (“ASC”) 350-40 (“ASC 350-40”) to address a customer’s accounting for implementation costs incurred in a cloud computing arrangement (“CCA”) that is a service contract. ASU 2018-15 amends ASC 350 and clarifies that a customer should apply ASC 350-40 to determine which implementation costs should be capitalized in a CCA. ASU 2018-15 does not expand on existing disclosure requirements except to require a description of the nature of hosting arrangements that are service contracts. Entities are permitted to apply either a retrospective or prospective transition approach to adopt the guidance. The Partnership adopted ASU 2018-15 effective January 1, 2020 and concluded there was no material impact to the Partnership’s condensed consolidated financial statements.

NET INCOME PER UNIT AND CASH DI

NET INCOME PER UNIT AND CASH DISTRIBUTION	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
NET INCOME PER UNIT AND CASH DISTRIBUTION	NET INCOME PER UNIT AND CASH DISTRIBUTION Allocation of Net Income Net income per unit applicable to limited partners is computed by dividing limited partners’ interest in net income attributable to Ciner Corp, after deducting the general partner’s interest and any incentive distributions, by the weighted average number of outstanding common units. Our net income is allocated to the general partner and limited partners in accordance with their respective partnership percentages, after giving effect to priority income allocations for incentive distributions, if any, to our general partner, pursuant to our partnership agreement. Earnings in excess of distributions are allocated to the general partner and limited partners based on their respective ownership interests. Payments made to our unitholders are determined in relation to actual distributions declared and are not based on the net income allocations used in the calculation of net income per unit. In addition to the common units, we have also identified the general partner interest and incentive distribution rights (“IDRs”) as participating securities and use the two-class method when calculating the net income per unit applicable to limited partners, which is based on the weighted-average number of common units outstanding during the period. Potentially anti-dilutive units outstanding were immaterial for both the three months ended March 31, 2020 and 2019 . The net income attributable to limited partner unitholders and the weighted average units for calculating basic and diluted net income per limited partner units were as follows: Three Months Ended (In millions, except per unit data) 2020 2019 Numerator: Net income attributable to Ciner Resources LP $ 6.7 $ 12.3 Less: General partner’s interest in net income 0.1 0.2 Total limited partners’ interest in net income $ 6.6 $ 12.1 Denominator: Weighted average limited partner units outstanding: Weighted average limited partner units outstanding (basic) 19.7 19.7 Weighted average limited partner units outstanding (diluted) 19.7 19.7 Net income per limited partner units: Net income per limited partner unit (basic) $ 0.34 $ 0.61 Net income per limited partner unit (diluted) $ 0.34 $ 0.61 The calculation of limited partners’ interest in net income is as follows: Three Months Ended (In millions) 2020 2019 Net income attributable to common unitholders: Distributions (1) $ 6.7 $ 6.7 (Distributions in excess)/Undistributed earnings of net income (0.1 ) 5.4 Common unitholders’ interest in net income $ 6.6 $ 12.1 (1) Distributions declared per limited partner unit for the period $ 0.340 $ 0.340 Quarterly Distribution Declared On April 28, 2020 , the Partnership declared its first quarter 2020 quarterly cash distribution of $0.340 per unit. The quarterly cash distribution is payable on May 22, 2020 to unitholders of record on May 8, 2020 . Our general partner has considerable discretion in determining the amount of available cash, the amount of distributions and the decision to make any distribution. Although our partnership agreement requires that we distribute all of our available cash quarterly, there is no guarantee that we will make quarterly cash distributions to our unitholders at our current quarterly distribution level, at the minimum quarterly distribution level or at any other rate, and we have no legal obligation to do so. General Partner Interest and Incentive Distribution Rights Our partnership agreement provides that our general partner initially will be entitled to 2.0% of all distributions that we make prior to our liquidation. Our general partner has the right, but not the obligation, to contribute up to a proportionate amount of capital to us in order to maintain its 2.0% general partner interest if we issue additional units (other than the issuance of common units upon a reset of the IDRs). Our general partner currently has an approximate 2.0% ownership interest in the partnership. Our partnership agreement does not require that our general partner fund its capital contribution with cash. It may, instead, fund its capital contribution by contributing to us common units or other property. IDRs represent the right to receive increasing percentages ( 13.0% , 23.0% and 48.0% ) of quarterly distributions from operating surplus after we have achieved the minimum quarterly distribution and the target distribution levels. Our general partner currently holds the IDRs, but may transfer these rights separately from its general partner interest, subject to certain restrictions in our partnership agreement. Percentage Allocations of Distributions from Operating Surplus The following table illustrates the percentage allocations of distributions from operating surplus between the unitholders and our general partner based on the specified target distribution levels. The amounts set forth under the column heading “Marginal Percentage Interest in Distributions” are the percentage interests of our general partner and the unitholders in any distributions from operating surplus we distribute up to and including the corresponding amount in the column “Total Quarterly Distribution per Unit Target Amount.” The percentage interests shown for our unitholders and our general partner for the minimum quarterly distribution also apply to quarterly distribution amounts that are less than the minimum quarterly distribution, including for the declared quarterly distributions of $0.340 per unit for the first quarter of 2020. Under our partnership agreement, our general partner has considerable discretion to determine the amount of available cash (as defined therein) for distribution each quarter to the Partnership’s unitholders, including the discretion to establish cash reserves that would limit the amount of available cash eligible for distribution to the Partnership’s unitholders for any quarter. The Partnership does not guarantee that it will pay the target amount of the minimum quarterly distribution listed below (or any distributions) on its units in any quarter. The percentage interests set forth below for our general partner (1) include its 2.0% general partner interest, (2) assume that our general partner has contributed any additional capital necessary to maintain its 2.0% general partner interest, (3) assume that our general partner has not transferred its IDRs and (4) assume that we do not issue additional classes of equity securities. Marginal Percentage Interest in Distributions Total Quarterly Distribution per Unit Target Amount Unitholders General Partner Minimum Quarterly Distribution $0.5000 98.0 % 2.0 % First Target Distribution above $0.5000 up to $0.5750 98.0 % 2.0 % Second Target Distribution above $0.5750 up to $0.6250 85.0 % 15.0 % Third Target Distribution above $0.6250 up to $0.7500 75.0 % 25.0 % Thereafter above $0.7500 50.0 % 50.0 %

INVENTORY

INVENTORY	3 Months Ended
	Mar. 31, 2020
Inventory Disclosure [Abstract]
INVENTORY	INVENTORY Inventory consisted of the following: As of (In millions) March 31, December 31, Raw materials $ 11.1 $ 8.7 Finished goods 8.6 6.9 Stores inventory 11.3 8.6 Total $ 31.0 $ 24.2

DEBT

DEBT	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
DEBT	DEBT Long-term debt, net of debt issuance costs, consisted of the following: As of (In millions) March 31, December 31, Ciner Wyoming Credit Facility, unsecured principal expiring on August 1, 2022, variable interest rate as a weighted average rate of 2.31% and 3.27% at March 31, 2020 and December 31, 2019, respectively $ 146.5 $ 129.5 Ciner Wyoming Equipment Financing Arrangement, principal and interest due in monthly installments beginning in April 2020 through March 2028, fixed rate interest at 2.479% per annum 29.8 — Total debt 176.3 129.5 Current portion of long-term debt 2.9 — Total long-term debt $ 173.4 $ 129.5 Aggregate maturities required on long-term debt at March 31, 2020 are due in future years as follows: (In millions) Amount 2020 $ 2.2 2021 3.0 2022 149.6 2023 3.2 2024 3.3 Thereafter 15.2 Total $ 176.5 Ciner Wyoming Equipment Financing Arrangement On March 26, 2020, Ciner Wyoming and Banc of America Leasing & Capital, LLC, as lender (the “Lender”), entered into an equipment financing arrangement (the “Ciner Wyoming Equipment Financing Arrangement”) including a Master Loan and Security Agreement, dated as of March 25, 2020 (the “Master Agreement”) and an Equipment Security Note Number 001, dated as of March 25, 2020 (the “Initial Secured Note”), which provides the terms and conditions for the debt financing of certain equipment related to Ciner Wyoming’s new natural gas-fired turbine co-generation facility that became operational in March 2020. Each equipment financing under the Ciner Wyoming Equipment Financing Arrangement will be evidenced by the execution of one or more equipment notes (including the Initial Secured Note) that incorporate the terms and conditions of the Master Agreement (each, an “Equipment Note”). In order to secure the payment and performance of Ciner Wyoming’s obligations under the Ciner Wyoming Equipment Financing Arrangement and other debt obligations owed by Ciner Wyoming to Lender, Ciner Wyoming granted to the Lender a continuing security interest in all of Ciner Wyoming’s right, title and interest in and to the Equipment (as defined in the Master Agreement) and certain related collateral. The Ciner Wyoming Equipment Financing Arrangement (1) incorporates all covenants of Ciner Wyoming that are based upon a specified level or ratio relating to assets, liabilities, indebtedness, rentals, net worth, cash flow, earnings, profitability, or any other accounting-based measurement or test, now or hereafter existing, in the Ciner Wyoming Credit Facility (as defined herein), or in any applicable replacement credit facility accepted in writing by Lender and (2) includes customary events of default subject to applicable grace periods, including, among others, (i) payment defaults, (ii) certain mergers or changes in control of Ciner Wyoming, (iii) cross defaults with certain other indebtedness (a) to which the Lender is a party or (b) to third parties in excess of $10 million , and (iv) the commencement of certain insolvency proceedings or related events identified in the Master Agreement. Upon the occurrence of an event of default, in its discretion, the Lender may exercise certain remedies, including, among others, the ability to accelerate the maturity of any Equipment Note such that all amounts thereunder will become immediately due and payable, to take possession of the Equipment identified in any Equipment Note, and to charge Ciner Wyoming a default rate of interest on all then outstanding or thereafter incurred obligations under the Ciner Wyoming Equipment Financing Arrangement. Among other things, the Initial Secured Note: • has a principal amount of $30,000,000 ; • has a maturity date of March 26, 2028; • shall be payable by Ciner Wyoming to Lender in 96 consecutive monthly installments of principal and interest commencing on April 26, 2020 and continuing thereafter until the maturity date of the Initial Secured Note, which shall be in the amount of approximately $307,000 for the first 95 monthly installments and approximately $4,307,000 for the final monthly installment; and • entitles Ciner Wyoming to prepay all (but not less than all) of the outstanding principal balance of the Initial Secured Note (together with all accrued interest and other charges and amounts owed thereunder) at any time after one (1) year from the date of the Initial Secured Note, subject to Ciner Wyoming paying to Lender an additional prepayment amount determined by the amount of principal balance prepaid and the date such prepayment is made. Ciner Wyoming’s balance under the Ciner Wyoming Equipment Financing Arrangement at March 31, 2020 was $30.0 million ( $29.8 million net of financing costs). During three months ended March 31, 2020 , Ciner Wyoming recorded $0.2 million of debt issuance costs in association with the Ciner Wyoming Equipment Financing Arrangement. At March 31, 2020 , Ciner Wyoming was in compliance with all financial covenants of the Ciner Wyoming Equipment Financing Arrangement. Ciner Wyoming Credit Facility On August 1, 2017, Ciner Wyoming entered into a Credit Agreement (as amended, the “Ciner Wyoming Credit Facility”) with each of the lenders listed on the respective signature pages thereof and PNC Bank, National Association (“PNC Bank”), as administrative agent, swing line lender and a Letter of Credit (“L/C”) issuer. On February 28, 2020, the Ciner Wyoming Credit Facility was amended to, among other things, increase flexibility for debt financing to be incurred by Ciner Wyoming in connection with its new natural gas-fired turbine co-generation facility, including, among other things (i) increasing the basket for purchase money indebtedness permitted from $5.0 million to $30.0 million ; (ii) adding procedures for transition to a benchmark other than the Eurodollar Rate to determine the applicable interest rate (including reference to the Secured Overnight Financing Rate published by the Federal Reserve Bank of New York), with provisions applying to that alternate benchmark; and (iii) adding customary new provisions relating to qualified financial contracts, sanctions and anti-money laundering rules and laws. The Ciner Wyoming Credit Facility is a $225.0 million senior unsecured revolving credit facility with a syndicate of lenders, which will mature on the fifth anniversary of the closing date of such credit facility. The Ciner Wyoming Credit Facility provides for revolving loans to fund working capital requirements, capital expenditures, to consummate permitted acquisitions and for all other lawful partnership purposes. The Ciner Wyoming Credit Facility has an accordion feature that allows Ciner Wyoming to increase the available revolving borrowings under the facility by up to an additional $75.0 million , subject to Ciner Wyoming receiving increased commitments from existing lenders or new commitments from new lenders and the satisfaction of certain other conditions. In addition, the Ciner Wyoming Credit Facility includes a sublimit up to $20.0 million for same-day swing line advances and a sublimit up to $40.0 million for letters of credit. Ciner Wyoming’s obligations under the Ciner Wyoming Credit Facility are unsecured. The Ciner Wyoming Credit Facility contains various covenants and restrictive provisions that limit (subject to certain exceptions) Ciner Wyoming’s ability to: • make distributions on or redeem or repurchase units; • incur or guarantee additional debt; • make certain investments and acquisitions; • incur certain liens or permit them to exist; • enter into certain types of transactions with affiliates of Ciner Wyoming; • merge or consolidate with another company; and • transfer, sell or otherwise dispose of assets. The Ciner Wyoming Credit Facility also requires quarterly maintenance of a consolidated leverage ratio (as defined in the Ciner Wyoming Credit Facility) of not more than 3.00 to 1.00 and a consolidated interest coverage ratio (as defined in the Ciner Wyoming Credit Facility) of not less than 3.00 to 1.00. The Ciner Wyoming Credit Facility contains events of default customary for transactions of this nature, including (i) failure to make payments required under the Ciner Wyoming Credit Facility, (ii) events of default resulting from failure to comply with covenants and financial ratios in the Ciner Wyoming Credit Facility, (iii) the occurrence of a change of control, (iv) the institution of insolvency or similar proceedings against Ciner Wyoming and (v) the occurrence of a default under any other material indebtedness Ciner Wyoming may have. Upon the occurrence and during the continuation of an event of default, subject to the terms and conditions of the Ciner Wyoming Credit Facility, the administrative agent shall, at the request of the Required Lenders (as defined in the Ciner Wyoming Credit Facility), or may, with the consent of the Required Lenders, terminate all outstanding commitments under the Ciner Wyoming Credit Facility and may declare any outstanding principal of the Ciner Wyoming Credit Facility debt, together with accrued and unpaid interest, to be immediately due and payable. Under the Ciner Wyoming Credit Facility, a change of control is triggered if Ciner Corp and its wholly-owned subsidiaries, directly or indirectly, cease to own all of the equity interests, or cease to have the ability to elect a majority of the board of directors (or similar governing body) of our general partner (or any entity that performs the functions of the Partnership’s general partner). In addition, a change of control would be triggered if the Partnership ceases to own at least 50.1% of the economic interests in Ciner Wyoming or ceases to have the ability to elect a majority of the members of Ciner Wyoming’s board of managers. Loans under the Ciner Wyoming Credit Facility bear interest at Ciner Wyoming’s option at either: • a Base Rate, which equals the highest of (i) the federal funds rate in effect on such day plus 0.50% , (ii) the administrative agent’s prime rate in effect on such day or (iii) one-month LIBOR plus 1.0% , in each case, plus an applicable margin; or • the Eurodollar Rate plus an applicable margin; provided , that with respect to an applicable loan, if the Eurodollar Rate cannot be determined by the administrative agent or if the administrative agent or certain lenders determined that the Eurodollar Rate does not adequately and fairly reflect the cost to such lenders of funding an applicable loan, the administrative agent in consultation with Ciner Wyoming, may establish an alternative interest rate for the applicable loan. The unused portion of the Ciner Wyoming Credit Facility is subject to an unused line fee ranging from 0.225% to 0.300% per annum based on Ciner Wyoming’s then current consolidated leverage ratio. At March 31, 2020 , Ciner Wyoming was in compliance with all financial covenants of the Ciner Wyoming Credit Facility. Ciner Resources Credit Facility On August 1, 2017, the Partnership entered into a Credit Agreement (as amended, the “Ciner Resources Credit Facility”) with each of the lenders listed on the respective signature pages thereof and PNC Bank, as administrative agent, swing line lender and an L/C issuer. On February 28, 2020, the Ciner Resources Credit Facility was amended to, among other things, increase flexibility for debt financing to be incurred by Ciner Wyoming in connection with its new natural gas-fired turbine co-generation facility, including, among other things (i) increasing the basket for purchase money indebtedness permitted under the Ciner Resources Credit Facility from $5.0 million to $30.0 million ; (ii) adding procedures under the Ciner Resources Credit Facility for transition to a benchmark other than the Eurodollar Rate to determine the applicable interest rate (including reference to the Secured Overnight Financing Rate published by the Federal Reserve Bank of New York), with provisions applying to that alternate benchmark; and (iii) adding customary new provisions relating to qualified financial contracts, sanctions and anti-money laundering rules and laws. The Ciner Resources Credit Facility is a $10.0 million senior secured revolving credit facility with a syndicate of lenders, which will mature on the fifth anniversary of the closing date of such credit facility. The Ciner Resources Credit Facility provides for revolving loans to be available to fund distributions on the Partnership’s units and working capital requirements and capital expenditures, to consummate permitted acquisitions and for all other lawful partnership purposes. The Ciner Resources Credit Facility includes a sublimit up to $5.0 million for same-day swing line advances and a sublimit up to $5.0 million for letters of credit. The Partnership’s obligations under the Ciner Resources Credit Facility are guaranteed by each of the Partnership’s material domestic subsidiaries other than Ciner Wyoming. In addition, the Partnership’s obligations under the Ciner Resources Credit Facility are secured by a pledge of substantially all of the Partnership’s assets (subject to certain exceptions), including the membership interests held in Ciner Wyoming by the Partnership. The Ciner Resources Credit Facility contains various covenants and restrictive provisions that limit (subject to certain exceptions) the Partnership’s ability to (and the ability of the Partnership’s subsidiaries, including without limitation, Ciner Wyoming to): • make distributions on or redeem or repurchase units; • incur or guarantee additional debt; • make certain investments and acquisitions; • incur certain liens or permit them to exist; • enter into certain types of transactions with affiliates; • merge or consolidate with another company; and • transfer, sell or otherwise dispose of assets. The Ciner Resources Credit Facility also requires quarterly maintenance of a consolidated leverage ratio (as defined in the Ciner Resources Credit Facility) of not more than 3.00 to 1.00 and a consolidated interest coverage ratio (as defined in the Ciner Resources Credit Facility) of not less than 3.00 to 1.00. In addition, the Ciner Resources Credit Facility contains events of default customary for transactions of this nature, including (i) failure to make payments required under the Ciner Resources Credit Facility, (ii) events of default resulting from failure to comply with covenants and financial ratios, (iii) the occurrence of a change of control, (iv) the institution of insolvency or similar proceedings against the Partnership or its material subsidiaries and (v) the occurrence of a default under any other material indebtedness the Partnership (or any of its subsidiaries) may have, including the Ciner Wyoming Credit Facility. Upon the occurrence and during the continuation of an event of default, subject to the terms and conditions of the Ciner Resources Credit Facility, the lenders may terminate all outstanding commitments under the Ciner Resources Credit Facility and may declare any outstanding principal of the Ciner Resources Credit Facility debt, together with accrued and unpaid interest, to be immediately due and payable. Under the Ciner Resources Credit Facility, a change of control is triggered if Ciner Corp and its wholly-owned subsidiaries, directly or indirectly, cease to own all of the equity interests, or cease to have the ability to elect a majority of the board of directors (or similar governing body) of, Ciner Holdings or Ciner GP (or any entity that performs the functions of the Partnership’s general partner). In addition, a change of control would be triggered if the Partnership ceases to own at least 50.1% of the economic interests in Ciner Wyoming or ceases to have the ability to elect a majority of the members of Ciner Wyoming’s board of managers. Loans under the Ciner Resources Credit Facility bear interest at our option at either: • a Base Rate, which equals the highest of (i) the federal funds rate in effect on such day plus 0.50% , (ii) the administrative agent’s prime rate in effect on such day or (iii) one-month LIBOR plus 1.0% , in each case, plus an applicable margin; or • Eurodollar Rate plus an applicable margin; provided , that with respect to an applicable loan, if the Eurodollar Rate cannot be determined by the administrative agent or if the administrative agent or certain lenders determined that the Eurodollar Rate does not adequately and fairly reflect the cost to such lenders of funding an applicable loan, the administrative agent in consultation with Ciner Resources, may establish an alternative interest rate for the applicable loan. The unused portion of the Ciner Resources Credit Facility is subject to an unused line fee ranging from 0.225% to 0.300% based on our then current consolidated leverage ratio. At March 31, 2020 , the Partnership was in compliance with all financial covenants of the Ciner Resources Credit Facility. WE Soda and Ciner Enterprises Facilities Agreement On August 1, 2018, Ciner Enterprises, the entity that indirectly owns and controls our general partner, refinanced its existing credit agreement and entered into a new facilities agreement, to which WE Soda and Ciner Enterprises (as borrowers), and KEW Soda, WE Soda, certain related parties and Ciner Enterprises, Ciner Holdings and Ciner Corp (as original guarantors and together with the borrowers, the “Ciner obligors”), are parties (as amended and restated or otherwise modified, the “Facilities Agreement”), and certain related finance documents. The Facilities Agreement expires on August 1, 2025. Even though neither the Partnership nor Ciner Wyoming is a party or a guarantor under the Facilities Agreement, while any amounts are outstanding under the Facilities Agreement we will be indirectly affected by certain affirmative and restrictive covenants that apply to WE Soda and its subsidiaries (which include us). Besides the customary covenants and restrictions, the Facilities Agreement includes provisions that, without a waiver or amendment approved by lenders whose commitments are more than 66-2/3% of the total commitments under the Facilities Agreement to undertake such action, would (i) prevent transactions with our affiliates that could reasonably be expected to materially and adversely affect the interests of certain finance parties, (ii) restrict the ability to amend our limited partnership agreement or the general partner’s limited liability company agreement or our other constituency documents if such amendment could reasonably be expected to materially and adversely affect the interests of the lenders to the Facilities Agreement; and (iii) prevent actions that enable certain restrictions or prohibitions on our ability to upstream cash (including via distributions) to the borrowers under the Facilities Agreement. In addition, while the general partner’s interest is not subject to a lien under the Facilities Agreement, Ciner Enterprises’ ownership in Ciner Holdings, which directly owns the general partner, is subject to a lien under the Facilities Agreement, which enables the lenders under the Facilities Agreement to foreclose on such collateral and take control of the general partner if any of WE Soda or KEW Soda or certain of their related parties, or Ciner Enterprises, Ciner Corp or Ciner Holdings is unable to satisfy its respective obligations under the Facilities Agreement. As of March 31, 2020, WE Soda was in compliance with the covenants under the Facilities Agreement. However given the uncertainty surrounding the negative financial impact of COVID-19 on the economy, WE Soda management anticipates that, in the absence of a waiver, there are scenarios whereby WE Soda may not be in compliance with certain covenants within the next 12 months and there is no assurance that such waiver may be obtained, if required.

OTHER NON-CURRENT LIABILITIES

OTHER NON-CURRENT LIABILITIES	3 Months Ended
	Mar. 31, 2020
Asset Retirement Obligation Disclosure [Abstract]
OTHER NON-CURRENT LIABILITIES	OTHER NON-CURRENT LIABILITIES Other non-current liabilities consisted of the following: As of (In millions) March 31, December 31, Reclamation reserve $ 5.8 $ 5.7 Derivative instruments and hedges, fair value liabilities 4.5 2.9 Total $ 10.3 $ 8.6 A reconciliation of the Partnership’s reclamation reserve liability is as follows: For the period ended (In millions) March 31, December 31, Beginning reclamation reserve balance $ 5.7 $ 5.4 Accretion expense 0.1 0.3 Ending reclamation reserve balance $ 5.8 $ 5.7

EMPLOYEE COMPENSATION

EMPLOYEE COMPENSATION	3 Months Ended
	Mar. 31, 2020
Retirement Benefits [Abstract]
EMPLOYEE COMPENSATION	EMPLOYEE COMPENSATION The Partnership participates in various benefit plans offered and administered by Ciner Corp and is allocated its portions of the annual costs related thereto. The specific plans are as follows: Retirement Plans - Benefits provided under the pension plan for salaried employees and pension plan for hourly employees (collectively, the “Retirement Plans”) are based upon years of service and average compensation for the highest 60 consecutive months of the employee’s last 120 months of service, as defined. Each Retirement Plan covers substantially all full-time employees hired before May 1, 2001. Ciner Corp’s Retirement Plans had a net unfunded liability balance of $53.3 million and $54.8 million at March 31, 2020 and December 31, 2019 , respectively. Ciner Corp’s current funding policy is to contribute an amount within the range of the minimum required and the maximum tax-deductible contribution. The Partnership’s allocated portion of the Retirement Plan’s net periodic pension costs for the three months ended March 31, 2020 and 2019 were a benefit of $(0.4) million and expense of $0.2 million , respectively. Savings Plan - The 401(k) retirement plan (the “401(k) Plan”) covers all eligible hourly and salaried employees. Eligibility is limited to all domestic residents and any foreign expatriates who are in the United States indefinitely. The 401(k) Plan permits employees to contribute specified percentages of their compensation, while the Partnership makes contributions based upon specified percentages of employee contributions. Participants hired on or subsequent to May 1, 2001, will receive an additional contribution from the Partnership based on a percentage of the participant’s base pay. Contributions made to the 401(k) Plan for the three months ended March 31, 2020 and 2019 were $1.6 million and $1.4 million , respectively. Postretirement Benefits - Most of the Partnership’s employees are eligible for postretirement benefits other than pensions if they reach retirement age while still employed. The postretirement benefits are accounted for by Ciner Corp on an accrual basis over an employee’s period of service. The postretirement plan, excluding pensions, are not funded, and Ciner Corp has the right to modify or terminate the plan. The post-retirement plan had a net unfunded liability of $13.4 million and $13.8 million at March 31, 2020 and December 31, 2019 , respectively. The Partnership’s allocated portion of postretirement costs (benefit) for the three months ended March 31, 2020 and 2019 were $0.2 million and $(0.6) million , respectively. The prior period benefit was the result of previous plan changes that have fully amortized.

EQUITY - BASED COMPENSATION

EQUITY - BASED COMPENSATION	3 Months Ended
	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
EQUITY - BASED COMPENSATION	EQUITY - BASED COMPENSATION In July 2013, our general partner established the Ciner Resource Partners LLC 2013 Long-Term Incentive Plan (as amended to date, the “Plan” or “LTIP”). The Plan provides for awards in the form of common units, phantom units, distribution equivalent rights (“DERs”), cash awards and other unit-based awards. The key terms of our time restricted unit awards (“Time Restricted Unit Awards”), total return restricted performance unit awards (“TR Performance Unit Awards”) and performance based unit awards based on the achievement of certain financial, operating and safety-related performance metrics (“2019 Performance Unit Awards”), including all financial disclosures, are set forth in Part II, Item 8. “Financial Statements and Supplementary Data” of our 2019 Annual Report. All non-employee directors of us and our parents and subsidiaries are eligible to be selected to participate in the Plan. As of March 31, 2020 , subject to further adjustment as provided in the Plan, a total of 0.7 million common units were available for awards under the Plan. Any common units tendered by a participant in payment of the tax liability with respect to an award, including common units withheld from any such award, will not be available for future awards under the Plan. Common units awarded under the Plan may be reserved or made available from our authorized and unissued common units or from common units reacquired (through open market transactions or otherwise). Any common units issued under the Plan through the assumption or substitution of outstanding grants from an acquired company will not reduce the number of common units available for awards under the Plan. If any common units subject to an award under the Plan are forfeited, those forfeited units will again be available for awards under the Plan. The Partnership has made a policy election to recognize forfeitures as they occur in lieu of estimating future forfeiture activity under the Plan. Non-employee Director Awards There were no grants of non-employee director awards during the three months ended March 31, 2020 or 2019 . Time Restricted Unit Awards We grant restricted unit awards in the form of common units to certain employees that vest over a specified period of time, usually between one to three years, with vesting based on continued employment as of each applicable vesting date. Award recipients are entitled to distributions subject to the same restrictions as the underlying common unit. The awards are classified as equity awards, and are accounted for at fair value at grant date. The following table presents a summary of activity on the Time Restricted Unit Awards: Three Months Ended Three Months Ended (Units in whole numbers) Number of Common Units Grant-Date Average Fair Value per Unit (1) Number of Common Units Grant-Date Average Fair Value per Unit (1) Unvested at the beginning of period 55,454 $ 20.33 71,436 $ 27.56 Granted — — — — Vested (27,810 ) 22.94 (32,087 ) 27.85 Forfeited — — — — Unvested at the end of the period 27,644 $ 17.71 39,349 $ 27.33 (1) Determined by dividing the aggregate grant date fair value of awards by the number of common units. Total Return Performance Unit Awards Historically, we have granted TR Performance Unit Awards to certain employees. The TR Performance Unit Awards represent the right to receive a number of common units at a future date based on the achievement of market-based performance requirements in accordance with the TR Performance Unit Award agreement, and also include DERs representing the right to receive an amount equal to the accumulated cash distributions made during the period with respect to each common unit issued upon vesting. The TR Performance Unit Awards vest at the end of the performance period, usually between two to three years from the date of the grant. Performance is measured on the achievement of a specified level of total return (“TR”), relative to the TR of a peer group comprised of other limited partnerships. The potential payout ranges from 0 - 200% of the grant target quantity and is adjusted based on our total return performance relative to the peer group. For purposes of the table below the number of units are included at target quantity. We utilized a Monte Carlo simulation model to estimate the grant date fair value of TR Performance Unit Awards granted to employees, adjusted for market conditions. This type of award requires the input of highly subjective assumptions, including expected volatility and expected distribution yield. Historical and implied volatilities were used in estimating the fair value of these awards. The following table presents a summary of activity on the TR Performance Unit Awards: Three Months Ended Three Months Ended (Units in whole numbers) Number of Common Units Grant-Date Average Fair Value per Unit (1) Number of Common Units Grant-Date Average Fair Value per Unit (1) Unvested at the beginning of period 20,173 $ 41.79 52,974 $ 42.22 Granted — — — — Vested (9,058 ) 42.21 (4,766 ) 43.93 Forfeited — — — — Unvested at the end of the period 11,115 $ 41.59 48,208 $ 42.05 (1) Determined by dividing the aggregate grant date fair value of awards by the number of common units. 2019 Performance Unit Awards On September 23, 2019, the board of directors of our general partner approved a new form of performance unit award agreement (“2019 Performance Unit Award Agreement”) that will be used to grant 2019 Performance Unit Awards that are based upon the achievement of certain financial, operating and safety-related performance metrics pursuant to our LTIP, and approved grants of 2019 Performance Unit Awards to certain of our executives. In addition to being subject to all the general terms and conditions of our LTIP, the vesting of the 2019 Performance Unit Awards is linked to a weighted average consisting of internal performance metrics (as each is defined in the corresponding 2019 Performance Unit Award Agreement, and collectively referred to herein as the “Performance Metrics”) during a three-year performance period (the “Measurement Period”). The vesting of the 2019 Performance Unit Awards, and number of common units of the Partnership distributable pursuant to such vesting, is dependent on our performance relative to a pre-established budget over the Measurement Period (provided that the awardee remains continuously employed with our general partner or its affiliates or satisfies other service-related criteria through the end of the Measurement Period, except in certain cases of Changes in Control (as defined in our LTIP) or the awardee’s death or disability). Vested 2019 Performance Unit Awards are to be settled in our common units, with the number of such common units payable under the award for a given year in the Measurement Period to be calculated by multiplying the target number provided in the corresponding 2019 Performance Unit Award Agreement by a payout multiplier, which may range from 0% - 200% in each case, as determined by aggregating the corresponding weighted average assigned to the Performance Metrics. The 2019 Performance Unit Awards also contain DERs and entitle the recipient the right to receive an amount equal to the accumulated cash distributions made during the period with respect to each common unit issued. Upon vesting of the 2019 Performance Unit Awards, the award recipient is entitled to receive a cash payment equal to the sum of the distribution equivalents accumulated with respect to vested 2019 Performance Unit Awards during the period beginning on January 1, 2019 and ending on the applicable vesting date. The 2019 Performance Unit Awards granted to these award recipients have a performance cycle beginning on January 1, 2019 and ending December 31, 2021. The following table presents a summary of activity on the 2019 Performance Unit Awards for the period: Three Months Ended Three Months Ended (Units in whole numbers) Number of Common Units Grant-Date Average Fair Value per Unit (1) Number of Common Units Grant-Date Average Fair Value per Unit (1) Unvested at the beginning of period 35,908 $ 16.45 — $ — Granted — — — — Vested — — — — Forfeited — — — — Unvested at the end of the period 35,908 $ 16.45 — $ — (1) Determined by dividing the weighted average price per common unit on the date of grant. Unrecognized Compensation Expense A summary of the Partnership’s unrecognized compensation expense for its unvested restricted time and all performance based units, and the weighted-average periods over which the compensation expense is expected to be recognized are as follows: Three Months Ended Three Months Ended Unrecognized Compensation Expense (In millions) Weighted Average to be Recognized (In years) Unrecognized Compensation Expense (In millions) Weighted Average to be Recognized (In years) Time Restricted Unit Awards $ 0.5 1.76 $ 1.0 1.39 TR Performance Unit Awards 0.1 0.84 1.0 1.57 2019 Performance Unit Awards 0.3 1.84 — — Total $ 0.9 $ 2.0

ACCUMULATED OTHER COMPREHENSIVE

ACCUMULATED OTHER COMPREHENSIVE LOSS	3 Months Ended
	Mar. 31, 2020
Equity [Abstract]
ACCUMULATED OTHER COMPREHENSIVE LOSS	ACCUMULATED OTHER COMPREHENSIVE LOSS Accumulated Other Comprehensive Loss Accumulated other comprehensive loss, attributable to Ciner Resources, includes unrealized gains and losses on derivative financial instruments. Amounts recorded in accumulated other comprehensive loss as of March 31, 2020 and December 31, 2019 , and changes within the period, consisted of the following: (In millions) Gains and (Losses) on Cash Flow Hedges Balance at December 31, 2019 $ (3.0 ) Other comprehensive loss before reclassification (1.4 ) Amounts reclassified from accumulated other comprehensive loss 0.4 Net current period other comprehensive loss (1.0 ) Balance at March 31, 2020 $ (4.0 ) Other Comprehensive Loss Other comprehensive income/(loss), including the portion attributable to non-controlling interest, is derived from adjustments to reflect the unrealized gains/(loss) on derivative financial instruments. The components of other comprehensive income/(loss) consisted of the following: Three Months Ended (In millions) 2020 2019 Unrealized loss (gain) on derivatives: Mark to market adjustment on interest rate swap contracts $ (1.0 ) $ (0.2 ) Mark to market adjustment on natural gas forward contracts (1.1 ) 2.2 (Loss) gain on derivative financial instruments $ (2.1 ) $ 2.0 Reclassifications for the period The components of other comprehensive loss, attributable to Ciner Resources, that have been reclassified consisted of the following: Three Months Ended Affected Line Items on the Unaudited Condensed Consolidated Statements of Operations and Comprehensive Income (In millions) 2020 2019 Details about other comprehensive loss components: Gains and losses on cash flow hedges: Interest rate swap contracts $ — $ (0.1 ) Interest expense Natural gas forward contracts 0.4 (0.4 ) Cost of products sold Total reclassifications for the period $ 0.4 $ (0.5 )

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES From time to time we are party to various claims and legal proceedings related to our business. Although the outcome of these proceedings cannot be predicted with certainty, management does not currently expect any of the legal proceedings we are involved in to have a material effect on our business, financial condition and results of operations. We cannot predict the nature of any future claims or proceedings, nor the ultimate size or outcome of existing claims and legal proceedings and whether any damages resulting from them will be covered by insurance. Off-Balance Sheet Arrangements We have a self-bond agreement (the “Self-Bond Agreement”) with the Wyoming Department of Environmental Quality (“WDEQ”) under which we currently commit to pay directly for reclamation costs. The amount of the bond was $36.2 million at both March 31, 2020 and December 31, 2019 . In May 2019, the State of Wyoming enacted legislation that limits our and other mine operators’ ability to self-bond, which will require us to seek other acceptable financial instruments to provide additional assurances for our reclamation obligations. We expect to provide such assurances by securing a third-party surety bond no later than November 2020 but we cannot guarantee the availability, costs and terms of such surety bond. As of the date of this Report, we anticipate that any such impact on our net income and liquidity will be limited. The amount of such surety guarantee is subject to change upon periodic re-evaluation by the WDEQ’s Land Quality Division.

AGREEMENTS AND TRANSACTIONS WIT

AGREEMENTS AND TRANSACTIONS WITH AFFILIATES	3 Months Ended
	Mar. 31, 2020
Related Party Transactions [Abstract]
AGREEMENTS AND TRANSACTIONS WITH AFFILIATES	AGREEMENTS AND TRANSACTIONS WITH AFFILIATES Ciner Corp is the exclusive sales agent for the Partnership and through its membership in ANSAC, Ciner Corp is responsible for promoting and increasing the use and sale of soda ash and other refined or processed sodium products produced. ANSAC operates on a cooperative service-at-cost basis to its members such that typically any annual profit or loss is passed through to the members. On November 9, 2018, Ciner Corp delivered a notice to terminate its membership in ANSAC, a cooperative that serves as the primary international distribution channel for us as well as two other U.S. manufacturers of trona-based soda ash. The effective termination date of Ciner Corp’s membership in ANSAC is December 31, 2021 (the “ANSAC termination date”). Between now and the ANSAC termination date, Ciner Corp continues to have full ANSAC membership benefits and services. In the event an ANSAC member exits or the ANSAC cooperative is dissolved, the exiting members are obligated for their respective portion of the residual net assets or deficit of the cooperative. Potential liabilities associated with exiting ANSAC are not currently probable or estimable. ANSAC was our largest customer for the periods ended March 31, 2020 and 2019 , accounting for 47.2% and 59.4% , respectively, of our net sales. Although ANSAC has been our largest customer for the periods ended March 31, 2020 and 2019 , we anticipate that the impact of such termination on our net sales, net income and liquidity will be limited. We made this determination primarily based upon the belief that we will continue to be one of the lowest cost producers of soda ash in the global market. After the ANSAC termination date, we expect Ciner Corp will begin marketing soda ash directly on our behalf into international markets that are currently being served by ANSAC and intends to utilize the distribution network that has already been established by the global Ciner Group. We believe that by combining our volumes with Ciner Group’s soda ash exports from Turkey, Ciner Corp’s withdrawal from ANSAC will allow us to leverage the larger, global Ciner Group’s soda ash operations which we expect will eventually lower our cost position and improve our ability to optimize our market share both domestically and internationally. Further, being able to work with the global Ciner Group will provide us the opportunity to attract and efficiently serve larger global customers. In addition, the Partnership will need access to an international logistics infrastructure that includes, among other things, a domestic port for export capabilities. These export capabilities are currently being developed by Ciner Enterprises and options being evaluated range from continued outsourcing in the near term to developing its own port capabilities in the longer term. The development costs of export capabilities are currently being paid by Ciner Enterprises, who is evaluating how these costs might be allocated to the Partnership, which could include ownership by us and repayment for the development costs and related assets or a service agreement model for logistics services which includes reimbursements for development costs. Since a decision to allocate costs to the Partnership has not been made yet and the Partnership is not currently using any Ciner Enterprises export services, none of these development costs have been recorded by the Partnership through March 31, 2020 . All actual sales and marketing costs incurred by Ciner Corp are charged directly to the Partnership. Selling, general and administrative expenses also include amounts charged to the Partnership by its affiliates principally consisting of salaries, benefits, office supplies, professional fees, travel, rent and other costs of certain assets used by the Partnership. On October 23, 2015, the Partnership entered into a Services Agreement (the “Services Agreement”) with our general partner and Ciner Corp. Pursuant to the Services Agreement, Ciner Corp has agreed to provide the Partnership with certain corporate, selling, marketing, and general and administrative services, in return for which the Partnership has agreed to pay Ciner Corp an annual management fee and reimburse Ciner Corp for certain third-party costs incurred in connection with providing such services. In addition, under the limited liability company agreement governing Ciner Wyoming, Ciner Wyoming reimburses us for employees who operate our assets and for support provided to Ciner Wyoming. These transactions do not necessarily represent arm's length transactions and may not represent all costs if Ciner Wyoming operated on a standalone basis. The total selling, general and administrative costs charged to the Partnership by affiliates were as follows: Three Months Ended (In millions) 2020 2019 Ciner Corp $ 3.5 $ 4.6 ANSAC (1) 0.6 0.9 Total selling, general and administrative expenses - affiliates $ 4.1 $ 5.5 (1) ANSAC allocates its expenses to its members using a pro-rata calculation based on sales. Net sales to affiliates were as follows: Three Months Ended (In millions) 2020 2019 ANSAC $ 54.0 $ 77.5 Total $ 54.0 $ 77.5 The Partnership had accounts receivable from affiliates and due to affiliates as follows: As of March 31, December 31, March 31, December 31, (In millions) Accounts receivable from affiliates Due to affiliates ANSAC $ 49.0 $ 53.8 $ 0.6 $ 1.6 CIDT (1) — 5.5 — — Ciner Corp 37.2 35.7 1.4 1.4 Total $ 86.2 $ 95.0 $ 2.0 $ 3.0 (1) “CIDT” refers to Ciner Ic ve Dis Ticaret Anonim Sirketi, an export affiliate of the Partnership.

MAJOR CUSTOMERS AND SEGMENT REP

MAJOR CUSTOMERS AND SEGMENT REPORTING	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
MAJOR CUSTOMERS AND SEGMENT REPORTING	MAJOR CUSTOMERS AND SEGMENT REPORTING Our operations are similar in geography, nature of products we provide, and type of customers we serve. As the Partnership earns substantially all of its revenues through the sale of soda ash mined at a single location in the Green River Basin of Wyoming, we have concluded that we have one operating segment for reporting purposes. The net sales by geographic area are as follows: Three Months Ended (In millions) 2020 2019 Domestic $ 55.2 $ 52.9 International ANSAC 54.0 77.5 Other 5.2 — Total international 59.2 77.5 Total net sales $ 114.4 $ 130.4

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS The Partnership measures certain financial and non-financial assets and liabilities at fair value on a recurring basis. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market in an orderly transaction between market participants on the measurement date. Fair value disclosures are reflected in a three-level hierarchy, maximizing the use of observable inputs and minimizing the use of unobservable inputs. A three-level valuation hierarchy is based upon the transparency of inputs to the valuation of an asset or liability on the measurement date. The three levels are defined as follows: Ÿ Level 1-inputs to the valuation methodology are quoted prices (unadjusted) for an identical asset or liability in an active market. Ÿ Level 2-inputs to the valuation methodology include quoted prices for a similar asset or liability in an active market or model-derived valuations in which all significant inputs are observable for substantially the full term of the asset or liability. Ÿ Level 3-inputs to the valuation methodology are unobservable and significant to the fair value measurement of the asset or liability. Financial instruments consist primarily of cash and cash equivalents, accounts receivable, accounts payable and long-term debt. The carrying amounts of cash and cash equivalents, accounts receivable and accounts payable approximate their fair value because of the nature of such instruments. Our derivative financial instruments are measured at their fair value with Level 2 inputs based on quoted market values for similar but not identical financial instruments. Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis Derivative Financial Instruments We have interest rate swap contracts, designated as cash flow hedges, to mitigate our exposure to possible increases in interest rates. The swap contracts consist of four individual $12.5 million swaps with an aggregate notional value of $50.0 million at March 31, 2020 and December 31, 2019 . The swaps have various maturities through 2023. We enter into natural gas forward contracts, designated as cash flow hedges, to mitigate volatility in the price of natural gas related to a portion of the natural gas we consume. These contracts generally have various maturities through 2024 . These contracts had an aggregate notional value of $30.4 million and $31.2 million at March 31, 2020 and December 31, 2019 , respectively. The following table presents the fair value of derivative assets and derivative liabilities and the respective locations on our unaudited condensed consolidated balance sheets as of March 31, 2020 and December 31, 2019 : Assets Liabilities March 31, December 31, March 31, December 31, (In millions) Balance Sheet Location Fair Value Fair Value Balance Sheet Location Fair Value Fair Value Derivatives designated as hedges: Interest rate swap contracts - current Other current assets $ — $ — Accrued Expenses $ 0.1 $ 0.9 Natural gas forward contracts - current Other current assets 0.1 0.1 Accrued Expenses 3.7 2.4 Natural gas forward contracts - non-current Other non-current assets 0.2 0.2 Other non-current liabilities 2.7 2.9 Interest rate swap contracts - non-current — — Other non-current liabilities 1.8 — Total fair value of derivatives designated as hedging instruments $ 0.3 $ 0.3 $ 8.3 $ 6.2 Financial Assets and Liabilities not Measured at Fair Value The carrying value of our long-term debt materially reflects the fair value of our long-term debt as its key terms are similar to indebtedness with similar amounts, durations and credit risks. See Note 4 “Debt” for additional information on our debt arrangements.

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	3 Months Ended
	Mar. 31, 2020
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS Quarterly Distributions Effective as of May 8, 2020, the members of the Board of Managers of Ciner Wyoming LLC, approved a cash distribution to the members of Ciner Wyoming in the aggregate amount of $14.5 million . This distribution is payable on May 21, 2020. On April 28, 2020 , the Partnership declared a cash distribution approved by the board of directors of our general partner. The cash distribution for the first quarter of 2020 of $0.340 per unit will be paid on May 22, 2020 to unitholders of record on May 8, 2020 .

CORPORATE STRUCTURE AND SUMMA_2

CORPORATE STRUCTURE AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Nature of Operations	Nature of Operations The unaudited condensed consolidated financial statements are composed of Ciner Resources LP (the “Partnership,” “CINR,” “Ciner Resources,” “we,” “us,” or “our”), a publicly traded Delaware limited partnership, and its consolidated subsidiary, Ciner Wyoming LLC (“Ciner Wyoming”), which is in the business of mining trona ore to produce soda ash. The Partnership’s operations consist solely of its investment in Ciner Wyoming. The Partnership was formed in April 2013 by Ciner Wyoming Holding Co. (“Ciner Holdings”), a wholly-owned subsidiary of Ciner Resources Corporation (“Ciner Corp”). Ciner Corp is a direct wholly-owned subsidiary of Ciner Enterprises Inc. (“Ciner Enterprises”), which is a direct wholly-owned subsidiary of WE Soda Ltd., a U.K. corporation (“WE Soda”). WE Soda is a direct wholly-owned subsidiary of KEW Soda Ltd., a U.K. corporation (“KEW Soda”), which is a direct wholly-owned subsidiary of Akkan Enerji ve Madencilik Anonim Şirketi (“Akkan”). Akkan is directly and wholly owned by Turgay Ciner, the Chairman of the Ciner Group (“Ciner Group”), a Turkish conglomerate of companies engaged in energy and mining (including soda ash mining), media and shipping markets. The Partnership owns a controlling interest comprised of 51.0% membership interest in Ciner Wyoming. All of our soda ash processed is currently sold to various domestic and international customers, including ANSAC which is an affiliate for export sales. All mining and processing activities of Ciner Wyoming take place in one facility located in the Green River Basin of Wyoming.
Basis of Presentation and Significant Accounting Policies	Basis of Presentation and Significant Accounting Policies The accompanying unaudited condensed consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles (“GAAP”) applicable to interim period financial statements and reflect all adjustments, consisting of normal recurring accruals, which are necessary for fair presentation of the results of operations, financial position and cash flows for the periods presented. All intercompany transactions, balances, revenue and expenses have been eliminated in consolidation. The results of operations for the three -month periods ended March 31, 2020 and 2019 are not necessarily indicative of the operating results for the full year. These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes to audited consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2019 (the “ 2019 Annual Report”) filed with the United States Securities and Exchange Commission on March 9, 2020. There have been no other material changes in the significant accounting policies followed by us during the three months ended March 31, 2020 from those disclosed in the 2019 Annual Report.
Use of Estimates	Use of Estimates The preparation of these unaudited condensed consolidated financial statements, in accordance with GAAP, 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 dates of the unaudited condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Furthermore, we considered the impact of the COVID-19 pandemic on the use of estimates and assumptions used for financial reporting and determined that there was no adverse material impact to our results of operations for the first quarter of 2020. While our production is considered “essential”, the COVID-19 outbreak could also disrupt our customers and customer segments, which could have a negative impact on the demand for our products which could materially adversely affect our operations. As a result of these uncertainties, actual results could differ from those estimates and assumptions. If the economy or markets in which we operate remain weak or deteriorate further, our business, financial condition and results of operations may be materially and adversely impacted.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements Recently Adopted Accounting Guidance In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-13, “Financial Instruments-Credit Losses (Topic 326)” (“ASU 2016-13”). This ASU introduces the current expected credit loss (CECL) model, which will require an entity to measure credit losses for certain financial instruments and financial assets, including trade receivables. Under this update, on initial recognition and at each reporting period, an entity will be required to recognize an allowance that reflects the entity’s current estimate of credit losses expected to be incurred over the life of the financial instrument. The Partnership adopted ASU 2016-13 effective January 1, 2020 and concluded there was no material impact to the Partnership’s condensed consolidated financial statements. In August 2018, the FASB issued ASU 2018-15, “Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (a consensus of the FASB Emerging Issues Task Force)” (“ASU 2018-15”), which amends Accounting Standards Codification (“ASC”) 350-40 (“ASC 350-40”) to address a customer’s accounting for implementation costs incurred in a cloud computing arrangement (“CCA”) that is a service contract. ASU 2018-15 amends ASC 350 and clarifies that a customer should apply ASC 350-40 to determine which implementation costs should be capitalized in a CCA. ASU 2018-15 does not expand on existing disclosure requirements except to require a description of the nature of hosting arrangements that are service contracts. Entities are permitted to apply either a retrospective or prospective transition approach to adopt the guidance. The Partnership adopted ASU 2018-15 effective January 1, 2020 and concluded there was no material impact to the Partnership’s condensed consolidated financial statements.

NET INCOME PER UNIT AND CASH _2

NET INCOME PER UNIT AND CASH DISTRIBUTION (Tables)	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Calculation of Net Income Per Unit	The net income attributable to limited partner unitholders and the weighted average units for calculating basic and diluted net income per limited partner units were as follows: Three Months Ended (In millions, except per unit data) 2020 2019 Numerator: Net income attributable to Ciner Resources LP $ 6.7 $ 12.3 Less: General partner’s interest in net income 0.1 0.2 Total limited partners’ interest in net income $ 6.6 $ 12.1 Denominator: Weighted average limited partner units outstanding: Weighted average limited partner units outstanding (basic) 19.7 19.7 Weighted average limited partner units outstanding (diluted) 19.7 19.7 Net income per limited partner units: Net income per limited partner unit (basic) $ 0.34 $ 0.61 Net income per limited partner unit (diluted) $ 0.34 $ 0.61
Calculation of Limited Partners' Interest in Net Income	The calculation of limited partners’ interest in net income is as follows: Three Months Ended (In millions) 2020 2019 Net income attributable to common unitholders: Distributions (1) $ 6.7 $ 6.7 (Distributions in excess)/Undistributed earnings of net income (0.1 ) 5.4 Common unitholders’ interest in net income $ 6.6 $ 12.1 (1) Distributions declared per limited partner unit for the period $ 0.340 $ 0.340
Percentage Allocations of Distributions From Operating Surplus	The following table illustrates the percentage allocations of distributions from operating surplus between the unitholders and our general partner based on the specified target distribution levels. The amounts set forth under the column heading “Marginal Percentage Interest in Distributions” are the percentage interests of our general partner and the unitholders in any distributions from operating surplus we distribute up to and including the corresponding amount in the column “Total Quarterly Distribution per Unit Target Amount.” The percentage interests shown for our unitholders and our general partner for the minimum quarterly distribution also apply to quarterly distribution amounts that are less than the minimum quarterly distribution, including for the declared quarterly distributions of $0.340 per unit for the first quarter of 2020. Under our partnership agreement, our general partner has considerable discretion to determine the amount of available cash (as defined therein) for distribution each quarter to the Partnership’s unitholders, including the discretion to establish cash reserves that would limit the amount of available cash eligible for distribution to the Partnership’s unitholders for any quarter. The Partnership does not guarantee that it will pay the target amount of the minimum quarterly distribution listed below (or any distributions) on its units in any quarter. The percentage interests set forth below for our general partner (1) include its 2.0% general partner interest, (2) assume that our general partner has contributed any additional capital necessary to maintain its 2.0% general partner interest, (3) assume that our general partner has not transferred its IDRs and (4) assume that we do not issue additional classes of equity securities. Marginal Percentage Interest in Distributions Total Quarterly Distribution per Unit Target Amount Unitholders General Partner Minimum Quarterly Distribution $0.5000 98.0 % 2.0 % First Target Distribution above $0.5000 up to $0.5750 98.0 % 2.0 % Second Target Distribution above $0.5750 up to $0.6250 85.0 % 15.0 % Third Target Distribution above $0.6250 up to $0.7500 75.0 % 25.0 % Thereafter above $0.7500 50.0 % 50.0 %

INVENTORY (Tables)

INVENTORY (Tables)	3 Months Ended
	Mar. 31, 2020
Inventory Disclosure [Abstract]
Schedule of Inventory	Inventory consisted of the following: As of (In millions) March 31, December 31, Raw materials $ 11.1 $ 8.7 Finished goods 8.6 6.9 Stores inventory 11.3 8.6 Total $ 31.0 $ 24.2

DEBT (Tables)

DEBT (Tables)	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Components of Long-term Debt	Long-term debt, net of debt issuance costs, consisted of the following: As of (In millions) March 31, December 31, Ciner Wyoming Credit Facility, unsecured principal expiring on August 1, 2022, variable interest rate as a weighted average rate of 2.31% and 3.27% at March 31, 2020 and December 31, 2019, respectively $ 146.5 $ 129.5 Ciner Wyoming Equipment Financing Arrangement, principal and interest due in monthly installments beginning in April 2020 through March 2028, fixed rate interest at 2.479% per annum 29.8 — Total debt 176.3 129.5 Current portion of long-term debt 2.9 — Total long-term debt $ 173.4 $ 129.5
Aggregate Maturities on Long-term Debt	Aggregate maturities required on long-term debt at March 31, 2020 are due in future years as follows: (In millions) Amount 2020 $ 2.2 2021 3.0 2022 149.6 2023 3.2 2024 3.3 Thereafter 15.2 Total $ 176.5

OTHER NON-CURRENT LIABILITIES (

OTHER NON-CURRENT LIABILITIES (Tables)	3 Months Ended
	Mar. 31, 2020
Asset Retirement Obligation Disclosure [Abstract]
Schedule of Other Non-current Liabilities	Other non-current liabilities consisted of the following: As of (In millions) March 31, December 31, Reclamation reserve $ 5.8 $ 5.7 Derivative instruments and hedges, fair value liabilities 4.5 2.9 Total $ 10.3 $ 8.6
Reconciliation of Partnership's Reclamation Reserve Liability	A reconciliation of the Partnership’s reclamation reserve liability is as follows: For the period ended (In millions) March 31, December 31, Beginning reclamation reserve balance $ 5.7 $ 5.4 Accretion expense 0.1 0.3 Ending reclamation reserve balance $ 5.8 $ 5.7

EQUITY - BASED COMPENSATION (Ta

EQUITY - BASED COMPENSATION (Tables)	3 Months Ended
	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
Schedule of Time Restricted Unit Award Activity	The following table presents a summary of activity on the Time Restricted Unit Awards: Three Months Ended Three Months Ended (Units in whole numbers) Number of Common Units Grant-Date Average Fair Value per Unit (1) Number of Common Units Grant-Date Average Fair Value per Unit (1) Unvested at the beginning of period 55,454 $ 20.33 71,436 $ 27.56 Granted — — — — Vested (27,810 ) 22.94 (32,087 ) 27.85 Forfeited — — — — Unvested at the end of the period 27,644 $ 17.71 39,349 $ 27.33 (1) Determined by dividing the aggregate grant date fair value of awards by the number of common units.
Schedule of Time Restricted Performance Unit Award Activity	The following table presents a summary of activity on the TR Performance Unit Awards: Three Months Ended Three Months Ended (Units in whole numbers) Number of Common Units Grant-Date Average Fair Value per Unit (1) Number of Common Units Grant-Date Average Fair Value per Unit (1) Unvested at the beginning of period 20,173 $ 41.79 52,974 $ 42.22 Granted — — — — Vested (9,058 ) 42.21 (4,766 ) 43.93 Forfeited — — — — Unvested at the end of the period 11,115 $ 41.59 48,208 $ 42.05 (1) Determined by dividing the aggregate grant date fair value of awards by the number of common units.
Schedule of Performance Unit Awards	The following table presents a summary of activity on the 2019 Performance Unit Awards for the period: Three Months Ended Three Months Ended (Units in whole numbers) Number of Common Units Grant-Date Average Fair Value per Unit (1) Number of Common Units Grant-Date Average Fair Value per Unit (1) Unvested at the beginning of period 35,908 $ 16.45 — $ — Granted — — — — Vested — — — — Forfeited — — — — Unvested at the end of the period 35,908 $ 16.45 — $ — (1) Determined by dividing the weighted average price per common unit on the date of grant.
Schedule of Unrecognized Compensation Expense	A summary of the Partnership’s unrecognized compensation expense for its unvested restricted time and all performance based units, and the weighted-average periods over which the compensation expense is expected to be recognized are as follows: Three Months Ended Three Months Ended Unrecognized Compensation Expense (In millions) Weighted Average to be Recognized (In years) Unrecognized Compensation Expense (In millions) Weighted Average to be Recognized (In years) Time Restricted Unit Awards $ 0.5 1.76 $ 1.0 1.39 TR Performance Unit Awards 0.1 0.84 1.0 1.57 2019 Performance Unit Awards 0.3 1.84 — — Total $ 0.9 $ 2.0

ACCUMULATED OTHER COMPREHENSI_2

ACCUMULATED OTHER COMPREHENSIVE LOSS (Tables)	3 Months Ended
	Mar. 31, 2020
Equity [Abstract]
Schedule of Accumulated Other Comprehensive Loss	Amounts recorded in accumulated other comprehensive loss as of March 31, 2020 and December 31, 2019 , and changes within the period, consisted of the following: (In millions) Gains and (Losses) on Cash Flow Hedges Balance at December 31, 2019 $ (3.0 ) Other comprehensive loss before reclassification (1.4 ) Amounts reclassified from accumulated other comprehensive loss 0.4 Net current period other comprehensive loss (1.0 ) Balance at March 31, 2020 $ (4.0 )
Components of Other Comprehensive Income/(Loss)	The components of other comprehensive income/(loss) consisted of the following: Three Months Ended (In millions) 2020 2019 Unrealized loss (gain) on derivatives: Mark to market adjustment on interest rate swap contracts $ (1.0 ) $ (0.2 ) Mark to market adjustment on natural gas forward contracts (1.1 ) 2.2 (Loss) gain on derivative financial instruments $ (2.1 ) $ 2.0
Schedule of Reclassifications Out of Other Comprehensive Loss, Attributable to Ciner Resources	The components of other comprehensive loss, attributable to Ciner Resources, that have been reclassified consisted of the following: Three Months Ended Affected Line Items on the Unaudited Condensed Consolidated Statements of Operations and Comprehensive Income (In millions) 2020 2019 Details about other comprehensive loss components: Gains and losses on cash flow hedges: Interest rate swap contracts $ — $ (0.1 ) Interest expense Natural gas forward contracts 0.4 (0.4 ) Cost of products sold Total reclassifications for the period $ 0.4 $ (0.5 )

AGREEMENTS AND TRANSACTIONS W_2

AGREEMENTS AND TRANSACTIONS WITH AFFILIATES (Tables)	3 Months Ended
	Mar. 31, 2020
Related Party Transactions [Abstract]
Schedule of Transactions with Affiliates	The Partnership had accounts receivable from affiliates and due to affiliates as follows: As of March 31, December 31, March 31, December 31, (In millions) Accounts receivable from affiliates Due to affiliates ANSAC $ 49.0 $ 53.8 $ 0.6 $ 1.6 CIDT (1) — 5.5 — — Ciner Corp 37.2 35.7 1.4 1.4 Total $ 86.2 $ 95.0 $ 2.0 $ 3.0 (1) “CIDT” refers to Ciner Ic ve Dis Ticaret Anonim Sirketi, an export affiliate of the Partnership. Net sales to affiliates were as follows: Three Months Ended (In millions) 2020 2019 ANSAC $ 54.0 $ 77.5 Total $ 54.0 $ 77.5 The total selling, general and administrative costs charged to the Partnership by affiliates were as follows: Three Months Ended (In millions) 2020 2019 Ciner Corp $ 3.5 $ 4.6 ANSAC (1) 0.6 0.9 Total selling, general and administrative expenses - affiliates $ 4.1 $ 5.5 (1) ANSAC allocates its expenses to its members using a pro-rata calculation based on sales.

MAJOR CUSTOMERS AND SEGMENT R_2

MAJOR CUSTOMERS AND SEGMENT REPORTING (Tables)	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Schedule of Net Sales By Geographic Area	The net sales by geographic area are as follows: Three Months Ended (In millions) 2020 2019 Domestic $ 55.2 $ 52.9 International ANSAC 54.0 77.5 Other 5.2 — Total international 59.2 77.5 Total net sales $ 114.4 $ 130.4

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Derivative Assets and Liabilities	The following table presents the fair value of derivative assets and derivative liabilities and the respective locations on our unaudited condensed consolidated balance sheets as of March 31, 2020 and December 31, 2019 : Assets Liabilities March 31, December 31, March 31, December 31, (In millions) Balance Sheet Location Fair Value Fair Value Balance Sheet Location Fair Value Fair Value Derivatives designated as hedges: Interest rate swap contracts - current Other current assets $ — $ — Accrued Expenses $ 0.1 $ 0.9 Natural gas forward contracts - current Other current assets 0.1 0.1 Accrued Expenses 3.7 2.4 Natural gas forward contracts - non-current Other non-current assets 0.2 0.2 Other non-current liabilities 2.7 2.9 Interest rate swap contracts - non-current — — Other non-current liabilities 1.8 — Total fair value of derivatives designated as hedging instruments $ 0.3 $ 0.3 $ 8.3 $ 6.2

CORPORATE STRUCTURE AND SUMMA_3

CORPORATE STRUCTURE AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - Ciner Wyoming	Mar. 31, 2020
Noncontrolling Interest [Line Items]
Membership interest	51.00%
Membership interest attributable to noncontrolling interest	49.00%

NET INCOME PER UNIT AND CASH _3

NET INCOME PER UNIT AND CASH DISTRIBUTION - Calculation of net income per unit (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Numerator:
Net income attributable to Ciner Resources LP	$ 6.7	$ 12.3
Less: General partner’s interest in net income	0.1	0.2
Total limited partners’ interest in net income	$ 6.6	$ 12.1
Weighted average limited partner units outstanding:
Weighted average common units outstanding (basic) (in shares)	19,700,000	19,700,000
Weighted average common units outstanding (diluted) (in shares)	19,700,000	19,700,000
Net income per limited partner units:
Net income per limited partner unit (basic) (in dollars per share)	$ 0.34	$ 0.61
Net income per limited partner units (diluted) (in dollars per share)	$ 0.34	$ 0.61
Distributions	$ 6.7	$ 6.7
(Distributions in excess)/Undistributed earnings of net income	(0.1)	5.4
Common unitholders’ interest in net income	$ 6.6	$ 12.1
Distributions declared per common unit for the period (in dollars per share)	$ 0.340	$ 0.340

NET INCOME PER UNIT AND CASH _4

NET INCOME PER UNIT AND CASH DISTRIBUTION - Narrative (Details) - $ / shares shares in Millions	Apr. 28, 2020	Mar. 31, 2020	Mar. 31, 2019
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)		0	0
Distributions declared per common unit for the period (in dollars per share)		$ 0.340	$ 0.340
Second Target Distribution | General Partner
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Increasing percentage allocation of operating surplus		13.00%
Third Target Distribution | General Partner
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Increasing percentage allocation of operating surplus		23.00%
Thereafter | General Partner
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Increasing percentage allocation of operating surplus		48.00%
Ciner Resource Partners LLC | General Partner
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Percentage of general partner ownership interest held		2.00%
Subsequent Event
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Distributions declared per common unit for the period (in dollars per share)	$ 0.34000

NET INCOME PER UNIT AND CASH _5

NET INCOME PER UNIT AND CASH DISTRIBUTION - Target distributions and marginal percentage interests (Details)	3 Months Ended
	Mar. 31, 2020$ / shares
Minimum Quarterly Distribution
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Minimum quarterly distribution target levels (in dollars per share)	$ 0.5000
First Target Distribution
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Minimum quarterly distribution target levels (in dollars per share)	0.5000
Maximum quarterly distribution target levels (in dollars per share)	0.5750
Second Target Distribution
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Minimum quarterly distribution target levels (in dollars per share)	0.5750
Maximum quarterly distribution target levels (in dollars per share)	0.6250
Third Target Distribution
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Minimum quarterly distribution target levels (in dollars per share)	0.6250
Maximum quarterly distribution target levels (in dollars per share)	0.7500
Thereafter
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Minimum quarterly distribution target levels (in dollars per share)	$ 0.7500
Unitholders | Minimum Quarterly Distribution
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Marginal interest in distribution, percentage	98.00%
Unitholders | First Target Distribution
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Marginal interest in distribution, percentage	98.00%
Unitholders | Second Target Distribution
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Marginal interest in distribution, percentage	85.00%
Unitholders | Third Target Distribution
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Marginal interest in distribution, percentage	75.00%
Unitholders | Thereafter
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Marginal interest in distribution, percentage	50.00%
General Partner | Minimum Quarterly Distribution
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Marginal interest in distribution, percentage	2.00%
General Partner | First Target Distribution
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Marginal interest in distribution, percentage	2.00%
General Partner | Second Target Distribution
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Marginal interest in distribution, percentage	15.00%
General Partner | Third Target Distribution
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Marginal interest in distribution, percentage	25.00%
General Partner | Thereafter
Schedule of Percentage Allocation of Distributions From Operating Surplus [Line Items]
Marginal interest in distribution, percentage	50.00%

INVENTORY (Details)

INVENTORY (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 11.1	$ 8.7
Finished goods	8.6	6.9
Stores inventory	11.3	8.6
Total	$ 31	$ 24.2

DEBT - Components of long-term

DEBT - Components of long-term debt (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total debt	$ 176.3	$ 129.5
Current portion of long-term debt	2.9	0
Total long-term debt	$ 173.4	$ 129.5
Ciner Wyoming Credit Facility | Revolving credit facility | Line of Credit
Debt Instrument [Line Items]
Weighted average interest rate	2.31%	3.27%
Total debt	$ 146.5	$ 129.5
Ciner Wyoming Equipment Financing Arrangement | Secured Debt
Debt Instrument [Line Items]
Stated interest rate	2.479%
Total debt	$ 29.8	$ 0

DEBT - Maturities of long-term

DEBT - Maturities of long-term debt (Details) $ in Millions	Mar. 31, 2020USD ($)
Debt Disclosure [Abstract]
2020	$ 2.2
2021	3
2022	149.6
2023	3.2
2024	3.3
Thereafter	15.2
Total	$ 176.5

DEBT - Ciner Wyoming Equipment

DEBT - Ciner Wyoming Equipment Financing Arrangement (Details)	3 Months Ended
	Mar. 31, 2020USD ($)installment	Dec. 31, 2019USD ($)
Debt Instrument [Line Items]
Long-term debt, gross	$ 176,500,000
Long-term debt	176,300,000	$ 129,500,000
Secured Debt | Ciner Wyoming Equipment Financing Arrangement
Debt Instrument [Line Items]
Face amount	$ 30,000,000
Number of installments | installment	96
Periodic payment	$ 307,000
Number of monthly installments | installment	95
Periodic payment terms, balloon payment to be paid	$ 4,307,000
Long-term debt, gross	30,000,000
Long-term debt	29,800,000	$ 0
Debt Issuance costs	200,000
Secured Debt | Ciner Wyoming Equipment Financing Arrangement | Minimum
Debt Instrument [Line Items]
Third party indebtedness	$ 10,000,000

DEBT DEBT - Ciner Wyoming Credi

DEBT DEBT - Ciner Wyoming Credit Facility (Details) - Line of Credit - Ciner Wyoming Credit Facility - USD ($)	3 Months Ended
	Mar. 31, 2020	Feb. 28, 2020	Aug. 01, 2017
Revolving credit facility
Debt Instrument [Line Items]
Capacity available for trade purchases		$ 30,000,000	$ 5,000,000
Maximum borrowing capacity	$ 225,000,000
Debt instrument, term	5 years
Accordion feature, increase limit	$ 75,000,000
Consolidated leverage ratio	3
Interest coverage ratio	3
Change of control percentage threshold	50.10%
Revolving credit facility | Minimum
Debt Instrument [Line Items]
Commitment fee percentage	0.225%
Revolving credit facility | Maximum
Debt Instrument [Line Items]
Commitment fee percentage	0.30%
Revolving credit facility | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Revolving credit facility | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Swing Line Advances
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 20,000,000
Letter of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 40,000,000

DEBT DEBT - Ciner Resources Cre

DEBT DEBT - Ciner Resources Credit Facility (Details) - Line of Credit - Ciner Resources Credit Facility - USD ($)	3 Months Ended
	Mar. 31, 2020	Feb. 28, 2020	Aug. 01, 2017
Revolving credit facility
Debt Instrument [Line Items]
Capacity available for trade purchases		$ 30,000,000	$ 5,000,000
Maximum borrowing capacity	$ 10,000,000
Debt instrument, term	5 years
Consolidated leverage ratio	3
Interest coverage ratio	3
Change of control percentage threshold	50.10%
Revolving credit facility | Minimum
Debt Instrument [Line Items]
Commitment fee percentage	0.225%
Revolving credit facility | Maximum
Debt Instrument [Line Items]
Commitment fee percentage	0.30%
Revolving credit facility | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Revolving credit facility | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Swing Line Advances
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 5,000,000
Letter of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 5,000,000

DEBT - WE Soda and Ciner Enterp

DEBT - WE Soda and Ciner Enterprises Facilities Agreement (Details)	Mar. 31, 2020
WE Soda and Ciner Enterprises Facilities Agreement
Debt Instrument [Line Items]
Commitment percentage threshold	66.67%

OTHER NON-CURRENT LIABILITIES_2

OTHER NON-CURRENT LIABILITIES (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Dec. 31, 2019
Asset Retirement Obligation Disclosure [Abstract]
Reclamation reserve	$ 5.8	$ 5.7	$ 5.8	$ 5.7
Derivative instruments and hedges, fair value liabilities			4.5	2.9
Total			$ 10.3	$ 8.6
Reclamation reserve
Beginning reclamation reserve balance	5.7	5.4
Accretion expense	0.1	0.3
Ending reclamation reserve balance	$ 5.8	$ 5.7

EMPLOYEE COMPENSATION (Details)

EMPLOYEE COMPENSATION (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2018	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Average compensation period	60 months
Period of last service	120 months
Retirement Plans
Defined Benefit Plan Disclosure [Line Items]
Net unfunded liability	$ 53.3			$ 54.8
Net periodic pension cost (credit)	(0.4)		$ 0.2
Savings Plan
Defined Benefit Plan Disclosure [Line Items]
Contributions made by employer	1.6	$ 1.4
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net unfunded liability	13.4			$ 13.8
Net periodic pension cost (credit)	$ 0.2		$ (0.6)

EQUITY - BASED COMPENSATION - N

EQUITY - BASED COMPENSATION - Narrative (Details) - $ / shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common units available under plan (shares)	700,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)	0	0
Vested (in dollars per share)	$ 22.94	$ 27.85
Restricted Stock Units (RSUs) | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
Restricted Stock Units (RSUs) | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Performance-Based Units | Total Return Performance Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)	0	0
Vested (in dollars per share)	$ 42.21	$ 43.93
Performance-Based Units | 2019 Performance Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)	0	0
Vested (in dollars per share)	$ 0	$ 0
Award vesting period	3 years
Performance-Based Units | Minimum | Total Return Performance Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	2 years
Payout range	0.00%
Performance-Based Units | Minimum | 2019 Performance Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout range	0.00%
Performance-Based Units | Maximum | Total Return Performance Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Payout range	200.00%
Performance-Based Units | Maximum | 2019 Performance Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout range	200.00%
Director - non employee | Common units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)	0	0

EQUITY - BASED COMPENSATION - S

EQUITY - BASED COMPENSATION - Schedule of Restricted Unit Award Activity (Details) - Restricted Stock Units (RSUs) - $ / shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Number of Common Units
Unvested at the beginning of period (in shares)	55,454	71,436
Granted (shares)	0	0
Vested (in shares)	(27,810)	(32,087)
Forfeited (in shares)	0	0
Unvested at the end of the period (in shares)	27,644	39,349
Grant-Date Average Fair Value per Unit
Unvested at the beginning of period (in dollars per share)	$ 20.33	$ 27.56
Granted (in dollars per share)	0	0
Vested (in dollars per share)	22.94	27.85
Forfeited (in dollars per share)	0	0
Unvested at the end of the period (in dollars per share)	$ 17.71	$ 27.33

EQUITY - BASED COMPENSATION -_2

EQUITY - BASED COMPENSATION - Schedule of Total Return Performance Unit Award Activity (Details) - Total Return Performance Unit Awards - Performance-Based Units - $ / shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Number of Common Units
Unvested at the beginning of period (in shares)	20,173	52,974
Granted (shares)	0	0
Vested (in shares)	(9,058)	(4,766)
Forfeited (in shares)	0	0
Unvested at the end of the period (in shares)	11,115	48,208
Grant-Date Average Fair Value per Unit
Unvested at the beginning of period (in dollars per share)	$ 41.79	$ 42.22
Granted (in dollars per share)	0	0
Vested (in dollars per share)	42.21	43.93
Forfeited (in dollars per share)	0	0
Unvested at the end of the period (in dollars per share)	$ 41.59	$ 42.05

EQUITY - BASED COMPENSATION EQU

EQUITY - BASED COMPENSATION EQUITY - BASED COMPENSATION - Performance Unit Awards (Details) - 2019 Performance Unit Awards - Performance-Based Units - $ / shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Number of Common Units
Unvested at the beginning of period (in shares)	35,908	0
Granted (shares)	0	0
Vested (in shares)	0	0
Forfeited (in shares)	0	0
Unvested at the end of the period (in shares)	35,908	0
Grant-Date Average Fair Value per Unit
Unvested at the beginning of period (in dollars per share)	$ 16.45	$ 0
Granted (in dollars per share)	0	0
Vested (in dollars per share)	0	0
Forfeited (in dollars per share)	0	0
Unvested at the end of the period (in dollars per share)	$ 16.45	$ 0

EQUITY - BASED COMPENSATION - U

EQUITY - BASED COMPENSATION - Unrecognized Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Unrecognized compensation expense	$ 0.9	$ 2
Time Restricted Unit Awards
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Unrecognized compensation expense	$ 0.5	$ 1
Weighted average to be recognized (in years)	1 year 9 months 4 days	1 year 4 months 21 days
Total Return Performance Unit Awards | Performance-Based Units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Unrecognized compensation expense	$ 0.1	$ 1
Weighted average to be recognized (in years)	10 months 2 days	1 year 6 months 26 days
2019 Performance Unit Awards | Performance-Based Units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Unrecognized compensation expense	$ 0.3	$ 0
Weighted average to be recognized (in years)	1 year 10 months 2 days	0 years

ACCUMULATED OTHER COMPREHENSI_3

ACCUMULATED OTHER COMPREHENSIVE LOSS - Schedule of Accumulated Other Comprehensive loss (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 299.9	$ 260.1
Net current period other comprehensive loss	(2.1)	2
Ending balance	298.2	$ 265.9
Gains and (Losses) on Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(3)
Other comprehensive loss before reclassification	(1.4)
Amounts reclassified from accumulated other comprehensive loss	0.4
Net current period other comprehensive loss	(1)
Ending balance	$ (4)

ACCUMULATED OTHER COMPREHENSI_4

ACCUMULATED OTHER COMPREHENSIVE LOSS - Components of Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized loss (gain) on derivative financial instruments	$ (2.1)	$ 2
Interest rate swap contracts
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized loss (gain) on derivative financial instruments	(1)	(0.2)
Natural gas forward contracts
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized loss (gain) on derivative financial instruments	$ (1.1)	$ 2.2

ACCUMULATED OTHER COMPREHENSI_5

ACCUMULATED OTHER COMPREHENSIVE LOSS - Schedule of Reclassifications out of Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest expense	$ 1.3	$ 1.4
Cost of products sold	86.6	90.2
Net income	14.2	25.2
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net income	0.4	(0.5)
Gains and (Losses) on Cash Flow Hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Total reclassifications for the period	(0.4)
Gains and (Losses) on Cash Flow Hedges | Interest rate swap contracts | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest expense	0	(0.1)
Gains and (Losses) on Cash Flow Hedges | Natural gas forward contracts | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Cost of products sold	$ 0.4	$ (0.4)

COMMITMENTS AND CONTINGENCIES -

COMMITMENTS AND CONTINGENCIES - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Self-bond agreement for reclamation costs
Other Commitments [Line Items]
Off balance sheet commitment	$ 36.2	$ 36.2

AGREEMENTS AND TRANSACTIONS W_3

AGREEMENTS AND TRANSACTIONS WITH AFFILIATES - Narrative (Details)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenue from Contract with Customer Benchmark | Customer Concentration Risk [Member] | ANSAC
Related Party Transaction [Line Items]
Concentration risk, percentage	47.20%	59.40%

AGREEMENTS AND TRANSACTIONS W_4

AGREEMENTS AND TRANSACTIONS WITH AFFILIATES - Costs charged by affiliates (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Sep. 30, 2018
Related Party Transaction [Line Items]
Total selling, general and administrative expenses - affiliates	$ 4.1	$ 5.5
Ciner Corp
Related Party Transaction [Line Items]
Total selling, general and administrative expenses - affiliates	3.5	4.6
ANSAC
Related Party Transaction [Line Items]
Total selling, general and administrative expenses - affiliates	$ 0.6	$ 0.9

AGREEMENTS AND TRANSACTIONS W_5

AGREEMENTS AND TRANSACTIONS WITH AFFILIATES - Net sales to affiliates (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2018
Related Party Transaction [Line Items]
Net sales to affiliates	$ 54	$ 77.5	$ 77.5
ANSAC
Related Party Transaction [Line Items]
Net sales to affiliates	$ 54		$ 77.5

AGREEMENTS AND TRANSACTIONS W_6

AGREEMENTS AND TRANSACTIONS WITH AFFILIATES - Receivables from or payables to affiliates (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Accounts receivable from affiliates	$ 86.2	$ 95
Due to affiliates	2	3
ANSAC
Related Party Transaction [Line Items]
Accounts receivable from affiliates	49	53.8
Due to affiliates	0.6	1.6
CIDT
Related Party Transaction [Line Items]
Accounts receivable from affiliates	0	5.5
Due to affiliates	0	0
Ciner Corp
Related Party Transaction [Line Items]
Accounts receivable from affiliates	37.2	35.7
Due to affiliates	$ 1.4	$ 1.4

MAJOR CUSTOMERS AND SEGMENT R_3

MAJOR CUSTOMERS AND SEGMENT REPORTING - Narrative (Details)	3 Months Ended
	Mar. 31, 2020segment
Segment Reporting [Abstract]
Number of operating segments	1

MAJOR CUSTOMERS AND SEGMENT R_4

MAJOR CUSTOMERS AND SEGMENT REPORTING - Sales by geographic area (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Sales by geographical area
Revenue by major product line	$ 114.4	$ 130.4
Domestic
Sales by geographical area
Revenue by major product line	55.2	52.9
International
Sales by geographical area
Revenue by major product line	59.2	77.5
International | ANSAC
Sales by geographical area
Revenue by major product line	54	77.5
Other | International
Sales by geographical area
Revenue by major product line	$ 5.2	$ 0

FAIR VALUE MEASUREMENTS - Narra

FAIR VALUE MEASUREMENTS - Narrative (Details) $ in Millions	Mar. 31, 2020USD ($)swap	Dec. 31, 2019USD ($)swap
Interest rate swap contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of swap contracts | swap	4	4
Natural gas forward contracts | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional amount	$ 30.4	$ 31.2
Designated as Hedging Instrument | Cash Flow Hedging | Interest rate swap contracts | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	12.5	12.5
Notional amount	$ 50	$ 50

FAIR VALUE MEASUREMENTS - Sched

FAIR VALUE MEASUREMENTS - Schedule of Fair Value of Derivative Assets and Liability (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset, noncurrent	$ 0		$ 0
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of derivatives designated as hedging instruments	0.3	$ 0.3
Total fair value of derivatives designated as hedging instruments	8.3	6.2
Other current assets | Fair Value, Measurements, Recurring | Interest rate swap contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset, current	0	0
Other current assets | Fair Value, Measurements, Recurring | Natural gas forward contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset, current	0.1	0.1
Other non-current assets | Fair Value, Measurements, Recurring | Natural gas forward contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset, noncurrent	0.2	0.2
Accrued Expenses | Fair Value, Measurements, Recurring | Interest rate swap contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability, current	0.1	0.9
Accrued Expenses | Fair Value, Measurements, Recurring | Natural gas forward contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability, current	3.7	2.4
Other non-current liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset, noncurrent			$ 0
Other non-current liabilities | Fair Value, Measurements, Recurring | Interest rate swap contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset, noncurrent	1.8
Other non-current liabilities | Fair Value, Measurements, Recurring | Natural gas forward contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability, noncurrent	$ 2.7	$ 2.9

SUBSEQUENT EVENTS - Narrative (

SUBSEQUENT EVENTS - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	May 08, 2020	Apr. 28, 2020	Mar. 31, 2020	Mar. 31, 2019
Subsequent Event [Line Items]
Distributions declared per common unit for the period (in dollars per share)			$ 0.340	$ 0.340
Subsequent Event
Subsequent Event [Line Items]
Cash distribution approved	$ 14.5
Distributions declared per common unit for the period (in dollars per share)		$ 0.34000