Document and Entity Information
Document and Entity Information - shares | 6 Months Ended | |
Jun. 30, 2019 | Jul. 30, 2019 | |
Document Information [Line Items] | ||
Document Type | 10-Q | |
Document Quarterly Report | true | |
Document Period End Date | Jun. 30, 2019 | |
Document Transition Report | false | |
Entity File Number | 001-36567 | |
Entity Registrant Name | Westlake Chemical Partners LP | |
Entity Incorporation, State or Country Code | DE | |
Entity Tax Identification Number | 32-0436529 | |
Entity Address, Address Line One | 2801 Post Oak Boulevard | |
Entity Address, Address Line Two | Suite 600 | |
Entity Address, City or Town | Houston | |
Entity Address, State or Province | TX | |
Entity Address, Postal Zip Code | 77056 | |
City Area Code | 713 | |
Local Phone Number | 585-2900 | |
Title of 12(b) Security | Common units representing limited partnership interests | |
Trading Symbol | WLKP | |
Security Exchange Name | NYSE | |
Entity Current Reporting Status | Yes | |
Entity Interactive Data Current | Yes | |
Entity Filer Category | Accelerated Filer | |
Entity Small Business | false | |
Entity Emerging Growth Company | false | |
Entity Shell Company | false | |
Entity Common Units, Units Outstanding | 35,188,189 | |
Amendment Flag | false | |
Document Fiscal Year Focus | 2019 | |
Document Fiscal Period Focus | Q2 | |
Entity Central Index Key | 0001604665 | |
Current Fiscal Year End Date | --12-31 |
Consolidated Balance Sheets
Consolidated Balance Sheets - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Current assets | ||
Cash and cash equivalents | $ 17,473 | $ 19,744 |
Receivable under the Investment Management Agreement—Westlake Chemical Corporation (Westlake) | 141,327 | 148,956 |
Accounts receivable, net—Westlake | 38,995 | 57,280 |
Accounts receivable, net—third parties | 20,435 | 16,404 |
Inventories | 4,029 | 4,388 |
Prepaid expenses and other current assets | 95 | 370 |
Total current assets | 222,354 | 247,142 |
Property, plant and equipment, net | 1,129,083 | 1,148,265 |
Goodwill | 5,814 | 5,814 |
Deferred charges and other assets, net | 53,653 | 60,904 |
Total assets | 1,410,904 | 1,462,125 |
Current liabilities | ||
Accounts payable—Westlake | 9,996 | 27,477 |
Accounts payable—third parties | 8,030 | 5,045 |
Accrued and other liabilities | 18,287 | 16,250 |
Total current liabilities | 36,313 | 48,772 |
Long-term debt payable to Westlake | 399,674 | 477,608 |
Deferred income taxes | 1,693 | 1,664 |
Operating lease liabilities | 1,110 | 0 |
Total liabilities | 438,790 | 528,044 |
Commitments and contingencies (Note 12) | ||
EQUITY | ||
Total Westlake Chemical Partners LP partners' capital | 277,791 | 215,810 |
Noncontrolling interest in Westlake Chemical OpCo LP (OpCo) | 694,323 | 718,271 |
Total equity | 972,114 | 934,081 |
Total liabilities and equity | 1,410,904 | 1,462,125 |
Limited Partner [Member] | Common units [Member] | Publicly and Privately Held [Member] | ||
EQUITY | ||
Limited Partners' Capital Account | 471,944 | 409,608 |
Total equity | 471,944 | 409,608 |
Limited Partner [Member] | Common units [Member] | Westlake [Member] | ||
EQUITY | ||
Limited Partners' Capital Account | 48,419 | 48,774 |
Total equity | 48,419 | 48,774 |
General Partner [Member] | Westlake [Member] | ||
EQUITY | ||
General partner—Westlake | (242,572) | (242,572) |
Total equity | $ (242,572) | $ (242,572) |
Consolidated Balance Sheets (Pa
Consolidated Balance Sheets (Parenthetical) - Common units [Member] - shares | Jun. 30, 2019 | Dec. 31, 2018 |
Publicly and Privately Held [Member] | ||
Units issued | 21,065,959 | 18,125,141 |
Units outstanding | 21,065,959 | 18,125,141 |
Westlake [Member] | ||
Units issued | 14,122,230 | 14,122,230 |
Units outstanding | 14,122,230 | 14,122,230 |
Consolidated Statements of Oper
Consolidated Statements of Operations - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Weighted Average Number of Limited Partnership and General Partnership Unit Outstanding, Basic and Diluted | 35,188,189 | 32,237,266 | 33,774,647 | 32,236,860 |
Net sales—Westlake | $ 230,047 | $ 253,673 | $ 487,087 | $ 488,704 |
Total net sales | 270,062 | 301,975 | 569,148 | 586,247 |
Cost of sales | 178,104 | 204,857 | 386,536 | 396,624 |
Gross profit | 91,958 | 97,118 | 182,612 | 189,623 |
Selling, general and administrative expenses | 7,639 | 7,375 | 14,612 | 14,508 |
Income from operations | 84,319 | 89,743 | 168,000 | 175,115 |
Other income (expense) | ||||
Interest expense—Westlake | (5,125) | (5,547) | (11,025) | (10,413) |
Other income, net | 1,153 | 583 | 1,968 | 1,074 |
Income before income taxes | 80,347 | 84,779 | 158,943 | 165,776 |
Income tax provision | 237 | 303 | 437 | 586 |
Net income | 80,110 | 84,476 | 158,506 | 165,190 |
Less: Net income attributable to noncontrolling interest in OpCo | 66,377 | 71,719 | 129,818 | 140,138 |
Net income attributable to Westlake Chemical Partners LP | $ 13,733 | $ 12,757 | $ 28,688 | $ 25,052 |
Common units [Member] | ||||
Weighted Average Number of Limited Partnership and General Partnership Unit Outstanding, Basic and Diluted | 35,188,189 | 32,237,266 | 33,774,647 | 32,236,860 |
Other income (expense) | ||||
Net income attributable to Westlake Chemical Partners LP | $ 13,733 | $ 12,757 | $ 28,688 | $ 24,319 |
Net Income (Loss), Per Outstanding Limited Partnership Unit, Basic, Net of Tax | $ 0.39 | $ 0.40 | $ 0.85 | $ 0.75 |
Common units [Member] | Publicly and Privately Held [Member] | ||||
Weighted Average Number of Limited Partnership and General Partnership Unit Outstanding, Basic and Diluted | 21,065,959 | 18,115,036 | 19,652,417 | 18,114,630 |
Common units [Member] | Westlake [Member] | ||||
Weighted Average Number of Limited Partnership and General Partnership Unit Outstanding, Basic and Diluted | 14,122,230 | 14,122,230 | 14,122,230 | 14,122,230 |
Product and Service, Other [Member] | ||||
Total net sales | $ 40,015 | $ 48,302 | $ 82,061 | $ 97,543 |
Consolidated Statements of Chan
Consolidated Statements of Changes in Equity - USD ($) $ in Thousands | Total | Accumulated Other Comprehensive Income (Loss) [Member] | Noncontrolling Interest in OpCo [Member] | Westlake [Member]General Partner [Member] | Common units [Member]Publicly and Privately Held [Member]Limited Partner [Member] | Common units [Member]Westlake [Member]Limited Partner [Member] |
Equity, beginning balance at Dec. 31, 2017 | $ 998,749 | $ 279 | $ 778,935 | $ (241,958) | $ 411,228 | $ 50,265 |
Net income | 80,714 | 68,419 | 733 | 6,498 | 5,064 | |
Net effect of cash flow hedge | 19 | 19 | ||||
Issuance of common units | 60 | 60 | ||||
Quarterly distributions to unitholders | (13,071) | (614) | (7,000) | (5,457) | ||
Quarterly distribution to noncontrolling interest retained in OpCo by Westlake | (91,148) | (91,148) | ||||
Equity, ending balance at Mar. 31, 2018 | 975,323 | 298 | 756,206 | (241,839) | 410,786 | 49,872 |
Equity, beginning balance at Dec. 31, 2017 | 998,749 | 279 | 778,935 | (241,958) | 411,228 | 50,265 |
Net income | 165,190 | |||||
Net Proceeds from private placement of common units | 0 | |||||
Equity, ending balance at Jun. 30, 2018 | 964,467 | 122 | 746,315 | (242,572) | 410,754 | 49,848 |
Equity, beginning balance at Mar. 31, 2018 | 975,323 | 298 | 756,206 | (241,839) | 410,786 | 49,872 |
Net income | 84,476 | 71,719 | 7,168 | 5,589 | ||
Net effect of cash flow hedge | (176) | (176) | ||||
Quarterly distributions to unitholders | (13,546) | (733) | (7,200) | (5,613) | ||
Quarterly distribution to noncontrolling interest retained in OpCo by Westlake | (81,610) | (81,610) | ||||
Equity, ending balance at Jun. 30, 2018 | 964,467 | 122 | 746,315 | (242,572) | 410,754 | 49,848 |
Equity, beginning balance at Dec. 31, 2018 | 934,081 | 0 | 718,271 | (242,572) | 409,608 | 48,774 |
Net income | 78,396 | 63,441 | 8,422 | 6,533 | ||
Net Proceeds from private placement of common units | 62,934 | 62,934 | ||||
Quarterly distributions to unitholders | (13,957) | (7,845) | (6,112) | |||
Quarterly distribution to noncontrolling interest retained in OpCo by Westlake | (81,507) | (81,507) | ||||
Equity, ending balance at Mar. 31, 2019 | 979,947 | 0 | 700,205 | (242,572) | 473,119 | 49,195 |
Equity, beginning balance at Dec. 31, 2018 | 934,081 | 0 | 718,271 | (242,572) | 409,608 | 48,774 |
Net income | 158,506 | |||||
Net Proceeds from private placement of common units | (62,916) | |||||
Equity, ending balance at Jun. 30, 2019 | 972,114 | 0 | 694,323 | (242,572) | 471,944 | 48,419 |
Equity, beginning balance at Mar. 31, 2019 | 979,947 | 0 | 700,205 | (242,572) | 473,119 | 49,195 |
Net income | 80,110 | 66,377 | 8,222 | 5,511 | ||
Offering costs related to private placement of common units | (18) | (18) | ||||
Quarterly distributions to unitholders | (15,666) | (9,379) | (6,287) | |||
Quarterly distribution to noncontrolling interest retained in OpCo by Westlake | (72,259) | (72,259) | ||||
Equity, ending balance at Jun. 30, 2019 | $ 972,114 | $ 0 | $ 694,323 | $ (242,572) | $ 471,944 | $ 48,419 |
Consolidated Statements of Cash
Consolidated Statements of Cash Flows - USD ($) $ in Thousands | 6 Months Ended | |
Jun. 30, 2019 | Jun. 30, 2018 | |
Cash flows from operating activities | ||
Net income | $ 158,506 | $ 165,190 |
Adjustments to reconcile net income to net cash provided by operating activities | ||
Depreciation and amortization | 53,701 | 55,284 |
Loss from disposition of property, plant and equipment | 458 | 567 |
Other losses (gains), net | (181) | 538 |
Changes in operating assets and liabilities | ||
Accounts receivable—third parties | (3,821) | 1,284 |
Net accounts receivable—Westlake | 419 | 2,885 |
Inventories | (402) | (538) |
Prepaid expenses and other current assets | 275 | 260 |
Accounts payable | 2,791 | (4,836) |
Accrued and other liabilities | 2,096 | 27 |
Other, net | (170) | (90) |
Cash flows from investing activities | 213,672 | 220,571 |
Cash flows from investing activities | ||
Additions to property, plant and equipment | (25,582) | (16,620) |
Maturities of investments with Westlake under the Investment Management Agreement | 344,445 | 178,000 |
Investments with Westlake under the Investment Management Agreement | (336,445) | (185,000) |
Other | 46 | 251 |
Net cash used for investing activities | (17,536) | (23,369) |
Cash flows from financing activities | ||
Net proceeds from private placement of common units | 62,916 | 0 |
Proceeds from debt payable to Westlake | 123,511 | 3,648 |
Repayment of debt payable to Westlake | (201,445) | 0 |
Quarterly distributions to noncontrolling interest retained in OpCo by Westlake | (153,766) | (172,758) |
Quarterly distributions to unitholders | (29,623) | (26,617) |
Net cash used for financing activities | (198,407) | (195,727) |
Net increase (decrease) in cash and cash equivalents | (2,271) | 1,475 |
Cash and cash equivalents at beginning of period | 19,744 | 27,008 |
Cash and cash equivalents at end of period | $ 17,473 | $ 28,483 |
Description of Business and Bas
Description of Business and Basis of Presentation | 6 Months Ended |
Jun. 30, 2019 | |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
Description of Business and Basis of Presentation | Description of Business and Basis of Presentation Description of Business Westlake Chemical Partners LP (the "Partnership") is a Delaware limited partnership formed in March 2014 to operate, acquire and develop ethylene production facilities and related assets. On August 4, 2014, the Partnership completed its initial public offering (the "IPO") of 12,937,500 common units representing limited partner interests. On September 29, 2017, the Partnership completed a secondary offering of 5,175,000 common units at a price of $22.00 per unit. On March 29, 2019, the Partnership completed the issuance and sale of 2,940,818 common units at a price of $21.40 per unit through a private placement. Net proceeds to Westlake Partners from the sale of the units were approximately $62,916 . In connection with the IPO, the Partnership acquired a 10.6% interest in Westlake Chemical OpCo LP ("OpCo") and a 100% interest in Westlake Chemical OpCo GP LLC ("OpCo GP"), which is the general partner of OpCo. On April 29, 2015, the Partnership purchased an additional 2.7% newly-issued limited partner interest in OpCo for approximately $135,341 , resulting in an aggregate 13.3% limited partner interest in OpCo, effective April 1, 2015. On September 29, 2017, the Partnership purchased an additional 5.0% newly-issued limited partner interest in OpCo for approximately $229,207 , resulting in an aggregate 18.3% limited partner interest in OpCo, effective as of July 1, 2017. On March 29, 2019, the Partnership purchased an additional 4.5% newly-issued limited partner interest in OpCo for approximately $201,445 , resulting in an aggregate 22.8% limited partner interest in OpCo, effective January 1, 2019. The remaining 77.2% limited partner interest in OpCo is owned by Westlake Chemical Corporation. OpCo owns three ethylene production facilities and a common carrier ethylene pipeline. Basis of Presentation The accompanying unaudited consolidated interim financial statements were prepared in accordance with the rules and regulations of the Securities and Exchange Commission (the "SEC") for interim periods. Accordingly, certain information and footnotes required for complete financial statements under generally accepted accounting principles in the United States ("U.S. GAAP") have not been included. These interim consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto of the Partnership included in the annual report on Form 10-K for the fiscal year ended December 31, 2018 (the " 2018 Form 10-K"), filed with the SEC on March 1, 2019 . These financial statements have been prepared in conformity with the accounting principles and practices as disclosed in the notes to the consolidated financial statements of the Partnership for the fiscal year ended December 31, 2018 with the exceptions of those accounting standards adopted in 2019 as discussed in Note 1 . References to "Westlake" refer collectively to Westlake Chemical Corporation and its subsidiaries, other than the Partnership, OpCo and OpCo GP. The Partnership holds a 22.8% limited partner interest and the entire non-economic general partner interest in OpCo. The remaining 77.2% limited partner interest in OpCo is owned by Westlake, which has no rights to direct the activities that most significantly impact the economic performance of OpCo. As a result of the fact that substantially all of OpCo's activities are conducted on behalf of Westlake, and the fact that OpCo exhibits disproportionality of voting rights to economic interest, OpCo was deemed to be a variable interest entity. The Partnership, through its ownership of OpCo's general partner, has the power to direct the activities that most significantly impact the economic performance of OpCo, and it also has the obligation or right to absorb losses or receive benefits from OpCo that could potentially be significant to OpCo. As such, the Partnership was determined to be OpCo's primary beneficiary and therefore consolidates OpCo's results of operations and financial position. Westlake's retained interest of 77.2% is recorded as noncontrolling interest in the Partnership's consolidated financial statements. In the opinion of the Partnership's management, the accompanying unaudited consolidated interim financial statements reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair statement of the Partnership's financial position as of June 30, 2019 , its results of operations for the three and six months ended June 30, 2019 and 2018 and the changes in its cash position for the six months ended June 30, 2019 and 2018 . Results of operations and changes in cash position for the interim periods presented are not necessarily indicative of the results that will be realized for the fiscal year ending December 31, 2019 or any other interim period. The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities. Actual results could differ materially from those estimates. Recent Accounting Pronouncements Credit Losses (ASU No. 2016-13) In June 2016, the FASB issued an accounting standards update providing new guidance for the accounting for credit losses on loans and other financial instruments. The new guidance introduces an approach based on expected losses to estimate credit losses on certain types of financial instruments. The standard also modifies the impairment model for available-for-sale debt securities and provides for a simplified accounting model for purchased financial assets with credit deterioration since their origination. The accounting standard will be effective for reporting periods beginning after December 15, 2019 and is not expected to have a material impact on the Partnership's consolidated financial position, results of operations and cash flows. Fair Value Measurement (ASU No. 2018-13) In August 2018, the FASB issued an accounting standards update to modify the disclosure requirements on fair value measurements. The amendments are effective for reporting periods beginning after December 15, 2019. An entity is permitted to early adopt any removed or modified disclosures and delay adoption of the additional disclosures until the effective date. Most amendments should be applied retrospectively but certain amendments should be applied prospectively. The Partnership is in the process of evaluating the impact that the new accounting guidance will have on the Partnership's consolidated financial position, results of operations and cash flows. Recently Adopted Accounting Standards Leases (ASU No. 2016-02) In February 2016, the FASB issued an accounting standards update on lease accounting that supersedes the previously issued lease guidance. The new standard requires lessees to recognize assets and liabilities for all long-term operating leases. An asset is recognized for the right to use an underlying leased asset and a liability is recognized for the obligation to make payments over the lease term. The standard also requires expanded lease disclosures. The standard requires a modified retrospective adoption approach and allows for the election of certain transition expedients. The Partnership adopted the standard effective January 1, 2019 using the optional transition method which allows entities to recognize a cumulative adjustment to the opening balance sheet in the period of adoption. The Partnership elected the package of optional transition expedients and was not required to reassess (1) whether any existing contracts are or contain leases, (2) classification of existing leases as operating or capital or (3) whether initial direct costs for existing leases qualify for capitalization under the new accounting standard. The Partnership did not elect the use of hindsight to determine the lease term when considering lease renewal or termination options. Adoption of the new standard did not have a material impact on the Partnership's consolidated financial position, results of operations and cash flows. |
Accounts Receivable - Third Par
Accounts Receivable - Third Parties | 6 Months Ended |
Jun. 30, 2019 | |
Accounts Receivable, Net [Abstract] | |
Accounts Receivable - Third Parties | Accounts Receivable—Third Parties Accounts receivable—third parties consist of the following: June 30, December 31, Trade customers $ 19,890 $ 17,325 Allowance for doubtful accounts (711 ) (921 ) 19,179 16,404 Other 1,256 — Accounts receivable, net—third parties $ 20,435 $ 16,404 |
Inventories
Inventories | 6 Months Ended |
Jun. 30, 2019 | |
Inventory Disclosure [Abstract] | |
Inventories | Inventories Inventories consist of the following: June 30, December 31, Finished products $ 3,587 $ 3,876 Feedstock, additives and chemicals 442 512 Inventories $ 4,029 $ 4,388 |
Property, Plant and Equipment
Property, Plant and Equipment | 6 Months Ended |
Jun. 30, 2019 | |
Property, Plant and Equipment [Abstract] | |
Property, Plant and Equipment | Property, Plant and Equipment Depreciation expense on property, plant and equipment of $22,227 and $22,044 is included in cost of sales in the consolidated statements of operations for the three months ended June 30, 2019 and 2018 , respectively. Depreciation expense on property, plant and equipment of $44,441 and $44,201 is included in cost of sales in the consolidated statements of operations for the six months ended June 30, 2019 and 2018 , respectively. |
Deferred Charges and Other Asse
Deferred Charges and Other Assets | 6 Months Ended |
Jun. 30, 2019 | |
Other Assets, Noncurrent [Abstract] | |
Deferred Charges and Other Assets | Deferred Charges and Other Assets Amortization expense on other assets of $4,630 and $5,542 is included in costs of sales in the consolidated statements of operations for the three months ended June 30, 2019 and 2018 , respectively. Amortization expense on other assets of $9,260 and $11,083 is included in costs of sales in the consolidated statements of operations for the six months ended June 30, 2019 and 2018 , respectively. |
Distributions and Net Income Pe
Distributions and Net Income Per Limited Partner Unit | 6 Months Ended |
Jun. 30, 2019 | |
Earnings Per Share [Abstract] | |
Distributions and Net Income Per Limited Partner Unit | Distributions and Net Income Per Limited Partner Unit On July 31, 2019 , the board of directors of Westlake Chemical Partners GP LLC ("Westlake GP"), the Partnership's general partner, declared a quarterly cash distribution for the three months ended June 30, 2019 of $0.4579 per unit. This distribution is payable on August 26, 2019 to the unitholders of record as of August 12, 2019 . The distributions are declared subsequent to quarter end; therefore, the table below represents total distributions declared from earnings of the related periods pertaining to such distributions. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Net income attributable to the Partnership $ 13,733 $ 12,757 $ 28,688 $ 25,052 Less: Limited partners' distributions declared on common units 16,113 13,179 31,779 25,993 Distributions declared with respect to the incentive distribution rights — — — 733 Distribution in excess of net income $ (2,380 ) $ (422 ) $ (3,091 ) $ (1,674 ) Net income per unit applicable to common limited partner units is computed by dividing the respective limited partners' interest in net income by the weighted-average number of common units outstanding for the period. Because the Partnership has more than one class of participating securities, it uses the two-class method when calculating the net income per unit applicable to limited partners. The classes of participating securities include common units and incentive distribution rights. Net income attributable to the Partnership is allocated to the unitholders in accordance with their respective ownership percentages in preparation of the consolidated statement of equity. However, when distributions related to the incentive distribution rights are made, net income equal to the amount of those distributions is first allocated to the general partner before the remaining net income is allocated to the unitholders based on their respective ownership percentages. Basic and diluted net income per unit is the same because the Partnership does not have any potentially dilutive units outstanding for the periods presented. Three Months Ended June 30, 2019 Limited Partners' Common Units Incentive Distribution Rights Total Net income attributable to the Partnership: Distribution declared $ 16,113 $ — $ 16,113 Distribution in excess of net income (2,380 ) — (2,380 ) Net income $ 13,733 $ — $ 13,733 Weighted average units outstanding: Basic and diluted 35,188,189 35,188,189 Net income per limited partner unit: Basic and diluted $ 0.39 Three Months Ended June 30, 2018 Limited Partners' Common Units Incentive Distribution Rights Total Net income attributable to the Partnership: Distribution declared $ 13,179 $ — $ 13,179 Distribution in excess of net income (422 ) — (422 ) Net income $ 12,757 $ — $ 12,757 Weighted average units outstanding: Basic and diluted 32,237,266 32,237,266 Net income per limited partner unit: Basic and diluted $ 0.40 Six Months Ended June 30, 2019 Limited Partners' Common Units Incentive Distribution Rights Total Net income attributable to the Partnership: Distribution declared $ 31,779 $ — $ 31,779 Distribution in excess of net income (3,091 ) — (3,091 ) Net income $ 28,688 $ — $ 28,688 Weighted average units outstanding: Basic and diluted 33,774,647 33,774,647 Net income per limited partner unit: Basic and diluted $ 0.85 Six Months Ended June 30, 2018 Limited Partners' Common Units Incentive Distribution Rights Total Net income attributable to the Partnership: Distribution declared $ 25,993 $ 733 $ 26,726 Distribution in excess of net income (1,674 ) — (1,674 ) Net income $ 24,319 $ 733 $ 25,052 Weighted average units outstanding: Basic and diluted 32,236,860 32,236,860 Net income per limited partner unit: Basic and diluted $ 0.75 The amended Partnership Agreement provides that the Partnership will distribute cash each quarter to all the unitholders, pro rata, until each unit has received a distribution of $1.2938 . If cash distributions to the Partnership's unitholders exceed $1.2938 per unit in any quarter, the Partnership's unitholders and Westlake, as the holder of the Partnership's incentive distribution rights, will receive distributions according to the following percentage allocations: Marginal Percentage Interest in Distributions Total Quarterly Distribution Per Unit Unitholders IDR Holders Above $1.2938 up to $1.4063 85.0 % 15.0 % Above $1.4063 up to $1.6875 75.0 % 25.0 % Above $1.6875 50.0 % 50.0 % The Partnership's distribution for the three months ended June 30, 2019 did not exceed the $1.2938 per unit threshold, and, as a result, no distribution was made with respect to the Partnership's incentive distribution rights to Westlake, as the holder of the Partnership's incentive distribution rights. Distribution Per Common Unit Distributions per common unit for the three and six months ended June 30, 2019 and 2018 were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Distributions per common unit $ 0.4452 $ 0.3975 $ 0.8780 $ 0.7839 |
Partners' Equity
Partners' Equity | 6 Months Ended |
Jun. 30, 2019 | |
Equity [Abstract] | |
Partners' Equity | 7. Partners' Equity On October 4, 2018, the Partnership and Westlake GP, the general partner of the Partnership, entered into an Equity Distribution Agreement with UBS Securities LLC, Barclays Capital Inc., Citigroup Global Markets Inc., Deutsche Bank Securities Inc., RBC Capital Markets, LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated and Wells Fargo Securities, LLC to offer and sell the Partnership's common units, from time to time, up to an aggregate offering amount of $50,000 . No common units had been issued under this program as of June 30, 2019 . On March 29, 2019, the Partnership completed the issuance and sale of 2,940,818 common units at a price of $21.40 per unit through a private placement. Net proceeds to the Partnership from the sale of the units were approximately $62,916 . TTWF LP, Westlake's principal stockholder and a related party, acquired 1,401,869 common units out of 2,940,818 common units issued in the private placement. |
Related Party Transactions
Related Party Transactions | 6 Months Ended |
Jun. 30, 2019 | |
Related Party Transactions [Abstract] | |
Related Party Transactions | Related Party Transactions The Partnership and OpCo regularly enter into related party transactions with Westlake. See below for a description of transactions with related parties. Sales to Related Parties OpCo sells ethylene to Westlake under the Ethylene Sales Agreement. Additionally, the Partnership and OpCo from time to time provide other services or products for which each charges Westlake a fee. Sales to related parties were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Net sales—Westlake $ 230,047 $ 253,673 $ 487,087 $ 488,704 Cost of Sales from Related Parties Charges for goods and services purchased by the Partnership and OpCo from Westlake and included in cost of sales relate primarily to feedstock purchased under the Feedstock Supply Agreement and services provided under the Services and Secondment Agreement. Charges from related parties in cost of sales were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Feedstock purchased from Westlake and included in cost of sales $ 89,599 $ 119,925 $ 211,754 $ 225,340 Other charges from Westlake and included in cost of sales 27,464 26,537 55,036 54,943 Total $ 117,063 $ 146,462 $ 266,790 $ 280,283 Services from Related Parties Included in Selling, General and Administrative Expenses Charges for services purchased by the Partnership from Westlake and included in selling, general and administrative expenses primarily relate to services Westlake performs on behalf of the Partnership under the Omnibus Agreement, including the Partnership's finance, legal, information technology, human resources, communication, ethics and compliance and other administrative functions. Charges from related parties included within selling, general and administrative expenses were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Services received from Westlake and included in selling, general and administrative expenses $ 6,464 $ 7,041 $ 13,067 $ 13,292 Goods and Services from Related Parties Capitalized as Assets Charges for goods and services purchased by the Partnership and OpCo from Westlake which were capitalized as assets relate primarily to the services of Westlake employees under the Services and Secondment Agreement. Charges from related parties for goods and services capitalized as assets were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Goods and services purchased from Westlake and capitalized as assets $ 641 $ 791 $ 1,284 $ 1,142 Receivable under the Investment Management Agreement On August 1, 2017, the Partnership, OpCo and Westlake executed an investment management agreement (the "Investment Management Agreement") that authorized Westlake to invest the Partnership's and OpCo's excess cash with Westlake for a term of up to a maximum of nine months. Per the terms of the Investment Management Agreement, the Partnership earns a market return plus five basis points and Westlake provides daily availability of the invested cash to meet any liquidity needs of the Partnership or OpCo. Accrued interest of $371 and $496 was included in the receivable under the Investment Management Agreement balance at June 30, 2019 and December 31, 2018 , respectively. Total interest earned related to the Investment Management Agreement was $1,155 and $568 for the three months ended June 30, 2019 and 2018 , respectively, and $1,973 and $1,108 for the six months ended June 30, 2019 and 2018 , respectively. The Partnership's receivable under the Investment Management Agreement was as follows: June 30, December 31, Receivable under the Investment Management Agreement $ 141,327 $ 148,956 Accounts Receivables The Partnership's accounts receivable from Westlake result primarily from ethylene sales to Westlake under the Ethylene Sales Agreement. The Partnership's accounts receivable from Westlake were as follows: June 30, December 31, Accounts receivable—Westlake $ 38,995 $ 57,280 Accounts Payable to Related Parties The Partnership's accounts payable to Westlake result primarily from feedstock purchases under the Feedstock Supply Agreement and services provided under the Services and Secondment Agreement and the Omnibus Agreement. The related party accounts payable balances were as follows: June 30, December 31, Accounts payable—Westlake $ 9,996 $ 27,477 Related Party Leases OpCo is obligated to Westlake under various rail cars leases. Operating lease rentals paid to Westlake for such leases were $562 and $700 for the three months ended June 30, 2019 and 2018 , respectively, and $1,076 and $1,018 for six months ended June 30, 2019 and 2018 , respectively, and reflected in other charges from Westlake that are included in cost of sales. OpCo has two site lease agreements with Westlake, each of which has a term of 50 years. Pursuant to the site lease agreements, OpCo pays Westlake one dollar per site per year. Debt Payable to Related Parties See Note 9 for a description of related party debt payable balances. Interest on related party debt payable balances for the three months ended June 30, 2019 and 2018 was $5,125 and $5,547 , respectively, and for the six months ended June 30, 2019 and 2018 was $11,025 and $10,413 , respectively. Interest on related party debt payable is presented as interest expense—Westlake in the consolidated statements of operations. Interest capitalized as a component of property, plant and equipment on related party debt was zero and $31 for the three months ended June 30, 2019 and 2018 , respectively, and for the six months ended June 30, 2019 and 2018 was zero and $46 , respectively. At June 30, 2019 and December 31, 2018 , accrued interest on related party debt was $5,384 and $5,448 , respectively, and is reflected as a component of accrued liabilities in the consolidated balance sheets. Debt payable to related parties was as follows: June 30, December 31, Long-term debt payable to Westlake $ 399,674 $ 477,608 Major Customer and Concentration of Credit Risk During the three months ended June 30, 2019 and 2018 , Westlake accounted for approximately 85.2% and 84.0% , respectively, of the Partnership's net sales. During the six months ended June 30, 2019 and 2018 , Westlake accounted for approximately 85.6% and 83.4% , respectively, of the Partnership's net sales. Other See Note 7 above for an additional related party transaction. |
Long-term Debt Payable to Westl
Long-term Debt Payable to Westlake | 6 Months Ended |
Jun. 30, 2019 | |
Related Party Transactions [Abstract] | |
Long-term Debt Payable to Westlake | Long-term Debt Payable to Westlake Long-term debt payable to Westlake consists of the following: June 30, December 31, OpCo Revolver (variable interest rate of LIBOR plus 2.0%, scheduled maturity of September 25, 2023) $ 22,619 $ 224,064 MLP Revolver (variable interest rate of LIBOR plus 2.0%, scheduled maturity of April 29, 2021) 377,055 253,544 $ 399,674 $ 477,608 On April 30, 2019, the Partnership repaid $201,445 of borrowings under the OpCo Revolver. On March 29, 2019, the Partnership borrowed $123,512 under the MLP Revolver to partially fund the purchase of the additional 4.5% interest in OpCo. The weighted average interest rate on all long-term debt was 4.6% and 4.4% , respectively, at June 30, 2019 and December 31, 2018 . As of June 30, 2019 , the Partnership was in compliance with all of the covenants under the OpCo Revolver and the MLP Revolver. |
Fair Value Measurements
Fair Value Measurements | 6 Months Ended |
Jun. 30, 2019 | |
Fair Value Disclosures [Abstract] | |
Fair Value Measurements | Fair Value Measurements The Partnership reports certain assets and liabilities at fair value, which is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). Under the accounting guidance for fair value measurements, inputs used to measure fair value are classified in one of three levels: Level 1: Quoted market prices in active markets for identical assets or liabilities. Level 2: Observable market-based inputs or unobservable inputs that are corroborated by market data. Level 3: Unobservable inputs that are not corroborated by market data. The Partnership has financial assets and liabilities subject to fair value measures. These financial assets and liabilities include accounts receivable, net, accounts payable and long-term debt payable to Westlake, all of which are recorded at carrying value. The amounts reported in the consolidated balance sheets for accounts receivable, net and accounts payable approximate their fair value due to the short maturities of these instruments. The carrying and fair values of the Partnership's long-term debt at June 30, 2019 and December 31, 2018 are summarized in the table below. The Partnership's long-term debt includes the OpCo Revolver and the MLP Revolver at June 30, 2019 . The fair value of debt is determined based on the present value of expected future cash flows using a discounted cash flow methodology. Because the Partnership's valuation methodology used for long-term debt requires the use of significant unobservable inputs, the inputs used to measure the fair value of the Partnership's long-term debt are classified as Level 3 within the fair value hierarchy. Inputs used to estimate the fair values of the Partnership's long-term debt include the selection of an appropriate discount rate. June 30, 2019 December 31, 2018 Carrying Value Fair Value Carrying Value Fair Value OpCo Revolver $ 22,619 $ 23,072 $ 224,064 $ 221,002 MLP Revolver 377,055 377,862 253,544 249,747 |
Supplemental Information
Supplemental Information | 6 Months Ended |
Jun. 30, 2019 | |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
Supplemental Information | Supplemental Information Accrued Liabilities Accrued liabilities were $18,287 and $16,250 at June 30, 2019 and December 31, 2018 , respectively. Accrued interest, accrued maintenance, capital expenditures and accrued taxes, which are components of accrued liabilities, were $5,384 , $2,451 , $2,057 and $3,975 , respectively, at June 30, 2019 , and $5,448 , $2,688 , $2,818 and $1,564 , respectively, at December 31, 2018 . No other component of accrued liabilities was more than five percent of total current liabilities. Non-cash Investing Activity The change in capital expenditure accrual resulted in an increase in additions to property, plant and equipment by $567 for the six months ended June 30, 2019 . The change in capital expenditure accrual resulted in a decrease in additions to property, plant and equipment by $5,042 for the six months ended June 30, 2018 . |
Commitments and Contingencies
Commitments and Contingencies | 6 Months Ended |
Jun. 30, 2019 | |
Commitments and Contingencies Disclosure [Abstract] | |
Commitments and Contingencies | Commitments and Contingencies The Partnership is subject to environmental laws and regulations that can impose civil and criminal sanctions and that may require the Partnership to mitigate the effects of contamination caused by the release or disposal of hazardous substances into the environment. These laws include the federal Clean Air Act, the federal Water Pollution Control Act, the Resource Conservation and Recovery Act ("RCRA"), the Comprehensive Environmental Response, Compensation, and Liability Act ("CERCLA"), the Toxic Substances Control Act and various other federal, state and local laws and regulations. Under CERCLA, an owner or operator of property may be held strictly liable for remediating contamination without regard to whether that person caused the contamination, and without regard to whether the practices that resulted in the contamination were legal at the time they occurred. Because the Partnership's production sites have a history of industrial use, it is impossible to predict precisely what effect these legal requirements will have on the Partnership. Westlake will indemnify the Partnership for liabilities that occurred or existed prior to August 4, 2014. The Partnership is involved in various legal proceedings incidental to the conduct of its business. The Partnership does not believe that any of these legal proceedings will have a material adverse effect on its financial condition, results of operations or cash flows. |
Description of Business and B_2
Description of Business and Basis of Presentation (Policies) | 6 Months Ended |
Jun. 30, 2019 | |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
Basis of Presentation | Basis of Presentation The accompanying unaudited consolidated interim financial statements were prepared in accordance with the rules and regulations of the Securities and Exchange Commission (the "SEC") for interim periods. Accordingly, certain information and footnotes required for complete financial statements under generally accepted accounting principles in the United States ("U.S. GAAP") have not been included. These interim consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto of the Partnership included in the annual report on Form 10-K for the fiscal year ended December 31, 2018 (the " 2018 Form 10-K"), filed with the SEC on March 1, 2019 . These financial statements have been prepared in conformity with the accounting principles and practices as disclosed in the notes to the consolidated financial statements of the Partnership for the fiscal year ended December 31, 2018 with the exceptions of those accounting standards adopted in 2019 as discussed in Note 1 . References to "Westlake" refer collectively to Westlake Chemical Corporation and its subsidiaries, other than the Partnership, OpCo and OpCo GP. The Partnership holds a 22.8% limited partner interest and the entire non-economic general partner interest in OpCo. The remaining 77.2% limited partner interest in OpCo is owned by Westlake, which has no rights to direct the activities that most significantly impact the economic performance of OpCo. As a result of the fact that substantially all of OpCo's activities are conducted on behalf of Westlake, and the fact that OpCo exhibits disproportionality of voting rights to economic interest, OpCo was deemed to be a variable interest entity. The Partnership, through its ownership of OpCo's general partner, has the power to direct the activities that most significantly impact the economic performance of OpCo, and it also has the obligation or right to absorb losses or receive benefits from OpCo that could potentially be significant to OpCo. As such, the Partnership was determined to be OpCo's primary beneficiary and therefore consolidates OpCo's results of operations and financial position. Westlake's retained interest of 77.2% is recorded as noncontrolling interest in the Partnership's consolidated financial statements. In the opinion of the Partnership's management, the accompanying unaudited consolidated interim financial statements reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair statement of the Partnership's financial position as of June 30, 2019 , its results of operations for the three and six months ended June 30, 2019 and 2018 and the changes in its cash position for the six months ended June 30, 2019 and 2018 . Results of operations and changes in cash position for the interim periods presented are not necessarily indicative of the results that will be realized for the fiscal year ending December 31, 2019 or any other interim period. The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities. Actual results could differ materially from those estimates. |
Recent Accounting Pronouncements | Recent Accounting Pronouncements Credit Losses (ASU No. 2016-13) In June 2016, the FASB issued an accounting standards update providing new guidance for the accounting for credit losses on loans and other financial instruments. The new guidance introduces an approach based on expected losses to estimate credit losses on certain types of financial instruments. The standard also modifies the impairment model for available-for-sale debt securities and provides for a simplified accounting model for purchased financial assets with credit deterioration since their origination. The accounting standard will be effective for reporting periods beginning after December 15, 2019 and is not expected to have a material impact on the Partnership's consolidated financial position, results of operations and cash flows. Fair Value Measurement (ASU No. 2018-13) In August 2018, the FASB issued an accounting standards update to modify the disclosure requirements on fair value measurements. The amendments are effective for reporting periods beginning after December 15, 2019. An entity is permitted to early adopt any removed or modified disclosures and delay adoption of the additional disclosures until the effective date. Most amendments should be applied retrospectively but certain amendments should be applied prospectively. The Partnership is in the process of evaluating the impact that the new accounting guidance will have on the Partnership's consolidated financial position, results of operations and cash flows. Recently Adopted Accounting Standards Leases (ASU No. 2016-02) In February 2016, the FASB issued an accounting standards update on lease accounting that supersedes the previously issued lease guidance. The new standard requires lessees to recognize assets and liabilities for all long-term operating leases. An asset is recognized for the right to use an underlying leased asset and a liability is recognized for the obligation to make payments over the lease term. The standard also requires expanded lease disclosures. The standard requires a modified retrospective adoption approach and allows for the election of certain transition expedients. The Partnership adopted the standard effective January 1, 2019 using the optional transition method which allows entities to recognize a cumulative adjustment to the opening balance sheet in the period of adoption. The Partnership elected the package of optional transition expedients and was not required to reassess (1) whether any existing contracts are or contain leases, (2) classification of existing leases as operating or capital or (3) whether initial direct costs for existing leases qualify for capitalization under the new accounting standard. The Partnership did not elect the use of hindsight to determine the lease term when considering lease renewal or termination options. Adoption of the new standard did not have a material impact on the Partnership's consolidated financial position, results of operations and cash flows. |
Accounts Receivable - Third P_2
Accounts Receivable - Third Parties (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Accounts Receivable, Net [Abstract] | |
Schedule Of Accounts Receivable - Third Parties | Accounts receivable—third parties consist of the following: June 30, December 31, Trade customers $ 19,890 $ 17,325 Allowance for doubtful accounts (711 ) (921 ) 19,179 16,404 Other 1,256 — Accounts receivable, net—third parties $ 20,435 $ 16,404 |
Inventories (Tables)
Inventories (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Inventory Disclosure [Abstract] | |
Schedule Of Inventory | Inventories consist of the following: June 30, December 31, Finished products $ 3,587 $ 3,876 Feedstock, additives and chemicals 442 512 Inventories $ 4,029 $ 4,388 |
Distributions and Net Income _2
Distributions and Net Income Per Limited Partner Unit (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Earnings Per Share [Abstract] | |
Distributions Made to Limited Partner, by Distribution [Table Text Block] | If cash distributions to the Partnership's unitholders exceed $1.2938 per unit in any quarter, the Partnership's unitholders and Westlake, as the holder of the Partnership's incentive distribution rights, will receive distributions according to the following percentage allocations: Marginal Percentage Interest in Distributions Total Quarterly Distribution Per Unit Unitholders IDR Holders Above $1.2938 up to $1.4063 85.0 % 15.0 % Above $1.4063 up to $1.6875 75.0 % 25.0 % Above $1.6875 50.0 % 50.0 % The Partnership's distribution for the three months ended June 30, 2019 did not exceed the $1.2938 per unit threshold, and, as a result, no distribution was made with respect to the Partnership's incentive distribution rights to Westlake, as the holder of the Partnership's incentive distribution rights. Distribution Per Common Unit Distributions per common unit for the three and six months ended June 30, 2019 and 2018 were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Distributions per common unit $ 0.4452 $ 0.3975 $ 0.8780 $ 0.7839 |
Schedule of Incentive Distributions Made to Managing Members or General Partners by Distribution | The distributions are declared subsequent to quarter end; therefore, the table below represents total distributions declared from earnings of the related periods pertaining to such distributions. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Net income attributable to the Partnership $ 13,733 $ 12,757 $ 28,688 $ 25,052 Less: Limited partners' distributions declared on common units 16,113 13,179 31,779 25,993 Distributions declared with respect to the incentive distribution rights — — — 733 Distribution in excess of net income $ (2,380 ) $ (422 ) $ (3,091 ) $ (1,674 ) |
Schedule of Earnings Per Share, Basic and Diluted | Net income per unit applicable to common limited partner units is computed by dividing the respective limited partners' interest in net income by the weighted-average number of common units outstanding for the period. Because the Partnership has more than one class of participating securities, it uses the two-class method when calculating the net income per unit applicable to limited partners. The classes of participating securities include common units and incentive distribution rights. Net income attributable to the Partnership is allocated to the unitholders in accordance with their respective ownership percentages in preparation of the consolidated statement of equity. However, when distributions related to the incentive distribution rights are made, net income equal to the amount of those distributions is first allocated to the general partner before the remaining net income is allocated to the unitholders based on their respective ownership percentages. Basic and diluted net income per unit is the same because the Partnership does not have any potentially dilutive units outstanding for the periods presented. Three Months Ended June 30, 2019 Limited Partners' Common Units Incentive Distribution Rights Total Net income attributable to the Partnership: Distribution declared $ 16,113 $ — $ 16,113 Distribution in excess of net income (2,380 ) — (2,380 ) Net income $ 13,733 $ — $ 13,733 Weighted average units outstanding: Basic and diluted 35,188,189 35,188,189 Net income per limited partner unit: Basic and diluted $ 0.39 Three Months Ended June 30, 2018 Limited Partners' Common Units Incentive Distribution Rights Total Net income attributable to the Partnership: Distribution declared $ 13,179 $ — $ 13,179 Distribution in excess of net income (422 ) — (422 ) Net income $ 12,757 $ — $ 12,757 Weighted average units outstanding: Basic and diluted 32,237,266 32,237,266 Net income per limited partner unit: Basic and diluted $ 0.40 Six Months Ended June 30, 2019 Limited Partners' Common Units Incentive Distribution Rights Total Net income attributable to the Partnership: Distribution declared $ 31,779 $ — $ 31,779 Distribution in excess of net income (3,091 ) — (3,091 ) Net income $ 28,688 $ — $ 28,688 Weighted average units outstanding: Basic and diluted 33,774,647 33,774,647 Net income per limited partner unit: Basic and diluted $ 0.85 Six Months Ended June 30, 2018 Limited Partners' Common Units Incentive Distribution Rights Total Net income attributable to the Partnership: Distribution declared $ 25,993 $ 733 $ 26,726 Distribution in excess of net income (1,674 ) — (1,674 ) Net income $ 24,319 $ 733 $ 25,052 Weighted average units outstanding: Basic and diluted 32,236,860 32,236,860 Net income per limited partner unit: Basic and diluted $ 0.75 |
Related Party Transactions (Tab
Related Party Transactions (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Related Party Transactions [Abstract] | |
Schedule of Related Party Transactions | Debt payable to related parties was as follows: June 30, December 31, Long-term debt payable to Westlake $ 399,674 $ 477,608 Charges from related parties included within selling, general and administrative expenses were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Services received from Westlake and included in selling, general and administrative expenses $ 6,464 $ 7,041 $ 13,067 $ 13,292 The Partnership's receivable under the Investment Management Agreement was as follows: June 30, December 31, Receivable under the Investment Management Agreement $ 141,327 $ 148,956 Sales to related parties were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Net sales—Westlake $ 230,047 $ 253,673 $ 487,087 $ 488,704 Charges from related parties in cost of sales were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Feedstock purchased from Westlake and included in cost of sales $ 89,599 $ 119,925 $ 211,754 $ 225,340 Other charges from Westlake and included in cost of sales 27,464 26,537 55,036 54,943 Total $ 117,063 $ 146,462 $ 266,790 $ 280,283 The Partnership's accounts receivable from Westlake were as follows: June 30, December 31, Accounts receivable—Westlake $ 38,995 $ 57,280 The related party accounts payable balances were as follows: June 30, December 31, Accounts payable—Westlake $ 9,996 $ 27,477 Charges from related parties for goods and services capitalized as assets were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Goods and services purchased from Westlake and capitalized as assets $ 641 $ 791 $ 1,284 $ 1,142 |
Long-term Debt Payable to Wes_2
Long-term Debt Payable to Westlake (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Related Party Transactions [Abstract] | |
Related Party Transactions, Long-term Debt | Long-term debt payable to Westlake consists of the following: June 30, December 31, OpCo Revolver (variable interest rate of LIBOR plus 2.0%, scheduled maturity of September 25, 2023) $ 22,619 $ 224,064 MLP Revolver (variable interest rate of LIBOR plus 2.0%, scheduled maturity of April 29, 2021) 377,055 253,544 $ 399,674 $ 477,608 |
Fair Value Measurements (Tables
Fair Value Measurements (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Fair Value Disclosures [Abstract] | |
Summary Of Carrying And Fair Values Of Long-Term Debt | The Partnership has financial assets and liabilities subject to fair value measures. These financial assets and liabilities include accounts receivable, net, accounts payable and long-term debt payable to Westlake, all of which are recorded at carrying value. The amounts reported in the consolidated balance sheets for accounts receivable, net and accounts payable approximate their fair value due to the short maturities of these instruments. The carrying and fair values of the Partnership's long-term debt at June 30, 2019 and December 31, 2018 are summarized in the table below. The Partnership's long-term debt includes the OpCo Revolver and the MLP Revolver at June 30, 2019 . The fair value of debt is determined based on the present value of expected future cash flows using a discounted cash flow methodology. Because the Partnership's valuation methodology used for long-term debt requires the use of significant unobservable inputs, the inputs used to measure the fair value of the Partnership's long-term debt are classified as Level 3 within the fair value hierarchy. Inputs used to estimate the fair values of the Partnership's long-term debt include the selection of an appropriate discount rate. June 30, 2019 December 31, 2018 Carrying Value Fair Value Carrying Value Fair Value OpCo Revolver $ 22,619 $ 23,072 $ 224,064 $ 221,002 MLP Revolver 377,055 377,862 253,544 249,747 |
Description of Business and B_3
Description of Business and Basis of Presentation (Details) $ / shares in Units, $ in Thousands | Mar. 29, 2019USD ($)$ / sharesshares | Sep. 29, 2017USD ($)$ / sharesshares | Apr. 29, 2015USD ($) | Apr. 01, 2015 | Aug. 04, 2014shares | Mar. 31, 2019USD ($) | Jun. 30, 2019USD ($)production_facility | Jun. 30, 2018USD ($) |
Limited Partners' Capital Account [Line Items] | ||||||||
Net proceeds from private placement of common units | $ 62,916 | $ (62,934) | $ 62,916 | $ 0 | ||||
Westlake Chemical OpCo LP [Member] | Affiliated Entity [Member] | ||||||||
Limited Partners' Capital Account [Line Items] | ||||||||
Limited partner interest | 22.80% | 18.30% | 13.30% | 10.60% | ||||
Limited partner interest, additional ownership | 4.50% | 5.00% | 2.70% | |||||
Amount paid to purchase additional limited partner interest | $ 201,445 | $ 229,207 | $ 135,341 | |||||
Westlake Chemical OpCo GP LLC [Member] | Limited Liability Company [Member] | ||||||||
Limited Partners' Capital Account [Line Items] | ||||||||
Limited partner interest | 100.00% | |||||||
Westlake [Member] | Westlake Chemical OpCo LP [Member] | Majority-Owned Subsidiary, Unconsolidated [Member] | ||||||||
Limited Partners' Capital Account [Line Items] | ||||||||
Limited partner interest | 77.20% | |||||||
Westlake Chemical OpCo LP [Member] | ||||||||
Limited Partners' Capital Account [Line Items] | ||||||||
Number of ethylene production facilities | production_facility | 3 | |||||||
Limited Partner [Member] | ||||||||
Limited Partners' Capital Account [Line Items] | ||||||||
Number of units sold in public offering | shares | 2,940,818 | 5,175,000 | 12,937,500 | |||||
Units sold in secondary offering price per unit (in dollars per share) | $ / shares | $ 21.40 | $ 22 |
Accounts Receivable - Third P_3
Accounts Receivable - Third Parties Accounts Receivable—Third Parties (Schedule Of Accounts Receivable) (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Accounts Receivable, Net [Abstract] | ||
Trade customers | $ 19,890 | $ 17,325 |
Allowance for doubtful accounts | (711) | (921) |
Trade Customer Receivable Net Current | 19,179 | 16,404 |
Other | 1,256 | 0 |
Accounts receivable, net—third parties | $ 20,435 | $ 16,404 |
Inventories (Details)
Inventories (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Inventory Disclosure [Abstract] | ||
Finished products | $ 3,587 | $ 3,876 |
Feedstock, additives and chemicals | 442 | 512 |
Inventories | $ 4,029 | $ 4,388 |
Property, Plant and Equipment (
Property, Plant and Equipment (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Property, Plant and Equipment [Abstract] | ||||
Depreciation expense on property, plant and equipment | $ 22,227 | $ 22,044 | $ 44,441 | $ 44,201 |
Deferred Charges and Other As_2
Deferred Charges and Other Assets (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Deferred Charges and Other Assets [Member] | ||||
Other Assets [Line Items] | ||||
Amortization expense | $ 4,630 | $ 5,542 | $ 9,260 | $ 11,083 |
Distributions and Net Income _3
Distributions and Net Income Per Limited Partner Unit (Distributions Declared) (Details) - USD ($) $ / shares in Units, $ in Thousands | Jul. 31, 2019 | Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 |
Distribution Made to Limited Partner [Line Items] | |||||
Distribution in excess of net income | $ (2,380) | $ (422) | $ (3,091) | $ (1,674) | |
Net income attributable to the Partnership | $ 13,733 | $ 12,757 | $ 28,688 | $ 25,052 | |
Weighted Average Number of Limited Partnership and General Partnership Unit Outstanding, Basic and Diluted | 35,188,189 | 32,237,266 | 33,774,647 | 32,236,860 | |
Distributions declared | $ 16,113 | $ 13,179 | $ 31,779 | $ 26,726 | |
IDR Holders [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Distribution in excess of net income | 0 | 0 | 0 | 0 | |
Net income attributable to the Partnership | 0 | 0 | 0 | 733 | |
Distributions declared with respect to the incentive distribution rights | 0 | 0 | 0 | 733 | |
Common units [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Distribution in excess of net income | (2,380) | (422) | (3,091) | (1,674) | |
Net income attributable to the Partnership | $ 13,733 | $ 12,757 | $ 28,688 | $ 24,319 | |
Weighted Average Number of Limited Partnership and General Partnership Unit Outstanding, Basic and Diluted | 35,188,189 | 32,237,266 | 33,774,647 | 32,236,860 | |
Distributions declared | $ 16,113 | $ 13,179 | $ 31,779 | $ 25,993 | |
Net Income (Loss), Per Outstanding Limited Partnership Unit, Basic, Net of Tax | $ 0.39 | $ 0.40 | $ 0.85 | $ 0.75 | |
Cash Distribution [Member] | IDR Holders [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Distributions declared with respect to the incentive distribution rights | $ 0 | $ 0 | $ 0 | $ 733 | |
Cash Distribution [Member] | Common units [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Distributions declared | $ 16,113 | $ 13,179 | $ 31,779 | $ 25,993 | |
Cash Distribution [Member] | Common And Subordinated Units [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Incentive Distribution Rights, Target Distribution Per Unit Requiring Marginal Percentage Distribution to IDR Holders | $ 1.2938 | ||||
Cash Distribution [Member] | Common And Subordinated Units [Member] | Subsequent Event [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Distribution declared per unit (in usd per unit) | $ 0.4579 | ||||
Above $1.2938 up to $1.4063 | Minimum [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Incentive Distribution Rights, Target Distribution Per Unit Requiring Marginal Percentage Distribution to IDR Holders | 1.2938 | ||||
Above $1.2938 up to $1.4063 | Maximum [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Incentive Distribution Rights, Target Distribution Per Unit Requiring Marginal Percentage Distribution to IDR Holders | $ 1.4063 | ||||
Above $1.2938 up to $1.4063 | Unit Holders [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Incentive Distribution, Marginal Percentage Interest in Distributions | 85.00% | ||||
Above $1.2938 up to $1.4063 | IDR Holders [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Incentive Distribution, Marginal Percentage Interest in Distributions | 15.00% | ||||
Above $1.4063 up to $1.6875 | Minimum [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Incentive Distribution Rights, Target Distribution Per Unit Requiring Marginal Percentage Distribution to IDR Holders | $ 1.4063 | ||||
Above $1.4063 up to $1.6875 | Maximum [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Incentive Distribution Rights, Target Distribution Per Unit Requiring Marginal Percentage Distribution to IDR Holders | $ 1.6875 | ||||
Above $1.4063 up to $1.6875 | Unit Holders [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Incentive Distribution, Marginal Percentage Interest in Distributions | 75.00% | ||||
Above $1.4063 up to $1.6875 | IDR Holders [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Incentive Distribution, Marginal Percentage Interest in Distributions | 25.00% | ||||
Above $1.6875 | Minimum [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Incentive Distribution Rights, Target Distribution Per Unit Requiring Marginal Percentage Distribution to IDR Holders | $ 1.6875 | ||||
Above $1.6875 | Unit Holders [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Incentive Distribution, Marginal Percentage Interest in Distributions | 50.00% | ||||
Above $1.6875 | IDR Holders [Member] | |||||
Distribution Made to Limited Partner [Line Items] | |||||
Incentive Distribution, Marginal Percentage Interest in Distributions | 50.00% |
Distributions and Net Income _4
Distributions and Net Income Per Limited Partner Unit (Income In Excess Of Distribution) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Incentive Distribution Made to Managing Member or General Partner [Line Items] | ||||
Net income attributable to the Partnership | $ 13,733 | $ 12,757 | $ 28,688 | $ 25,052 |
Distributions declared | 16,113 | 13,179 | 31,779 | 26,726 |
Distribution in excess of net income | (2,380) | (422) | (3,091) | (1,674) |
IDR Holders [Member] | ||||
Incentive Distribution Made to Managing Member or General Partner [Line Items] | ||||
Net income attributable to the Partnership | 0 | 0 | 0 | 733 |
Distributions declared with respect to the incentive distribution rights | 0 | 0 | 0 | 733 |
Distribution in excess of net income | 0 | 0 | 0 | 0 |
Common units [Member] | ||||
Incentive Distribution Made to Managing Member or General Partner [Line Items] | ||||
Net income attributable to the Partnership | 13,733 | 12,757 | 28,688 | 24,319 |
Distributions declared | 16,113 | 13,179 | 31,779 | 25,993 |
Distribution in excess of net income | (2,380) | (422) | (3,091) | (1,674) |
Cash Distribution [Member] | IDR Holders [Member] | ||||
Incentive Distribution Made to Managing Member or General Partner [Line Items] | ||||
Distributions declared with respect to the incentive distribution rights | 0 | 0 | 0 | 733 |
Cash Distribution [Member] | Common units [Member] | ||||
Incentive Distribution Made to Managing Member or General Partner [Line Items] | ||||
Distributions declared | $ 16,113 | $ 13,179 | $ 31,779 | $ 25,993 |
Distributions and Net Income _5
Distributions and Net Income Per Limited Partner Unit (Basic and Diluted Income Per Limited Partner Unit) (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Limited Partners' Capital Account [Line Items] | ||||
Distributions declared | $ 16,113 | $ 13,179 | $ 31,779 | $ 26,726 |
Distribution in excess of net income | (2,380) | (422) | (3,091) | (1,674) |
Net income | $ 13,733 | $ 12,757 | $ 28,688 | $ 25,052 |
Weighted Average Number of Limited Partnership and General Partnership Unit Outstanding, Basic and Diluted | 35,188,189 | 32,237,266 | 33,774,647 | 32,236,860 |
Common units [Member] | ||||
Limited Partners' Capital Account [Line Items] | ||||
Distributions declared | $ 16,113 | $ 13,179 | $ 31,779 | $ 25,993 |
Distribution in excess of net income | (2,380) | (422) | (3,091) | (1,674) |
Net income | $ 13,733 | $ 12,757 | $ 28,688 | $ 24,319 |
Weighted Average Number of Limited Partnership and General Partnership Unit Outstanding, Basic and Diluted | 35,188,189 | 32,237,266 | 33,774,647 | 32,236,860 |
Weighted average units outsanding: | ||||
Net Income (Loss), Per Outstanding Limited Partnership Unit, Basic, Net of Tax | $ 0.39 | $ 0.40 | $ 0.85 | $ 0.75 |
IDR Holders [Member] | ||||
Limited Partners' Capital Account [Line Items] | ||||
Subsequent distribution to IDR holders | $ 0 | $ 0 | $ 0 | $ 733 |
Distribution in excess of net income | 0 | 0 | 0 | 0 |
Net income | $ 0 | $ 0 | $ 0 | $ 733 |
Distributions and Net Income _6
Distributions and Net Income Per Limited Partner Unit (Distribution Per Common Unit) (Details) - $ / shares | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Distribution Per Common Unit [Abstract] | ||||
Distribution Made to Limited Partner, Distributions Paid, Per Unit | $ 0.4452 | $ 0.3975 | $ 0.8780 | $ 0.7839 |
Partners' Equity (Details)
Partners' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands | Mar. 29, 2019 | Oct. 04, 2018 | Sep. 29, 2017 | Aug. 04, 2014 | Mar. 31, 2019 | Jun. 30, 2019 | Jun. 30, 2018 |
Class of Stock [Line Items] | |||||||
Partners Units, Maximum Aggregate Offering Amount, ATM | $ 50 | ||||||
Net proceeds from private placement of common units | $ 62,916 | $ (62,934) | $ 62,916 | $ 0 | |||
Limited Partner [Member] | |||||||
Class of Stock [Line Items] | |||||||
Number of units sold in public offering | 2,940,818 | 5,175,000 | 12,937,500 | ||||
Units sold in secondary offering price per unit (in dollars per share) | $ 21.40 | $ 22 | |||||
Affiliated Entity [Member] | |||||||
Class of Stock [Line Items] | |||||||
Partners' Capital Account, Units, Sold to Related Party | 1,401,869 |
Related Party Transactions (Sal
Related Party Transactions (Sales to Related Parties) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Related Party Transactions [Abstract] | ||||
Revenue from Related Parties | $ 230,047 | $ 253,673 | $ 487,087 | $ 488,704 |
Related Party Transactions (Cos
Related Party Transactions (Cost of Sales from Related Parties) (Details) - Affiliated Entity [Member] - Westlake [Member] - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Related Party Transaction [Line Items] | ||||
Charges from related parties in cost of sales | $ 117,063 | $ 146,462 | $ 266,790 | $ 280,283 |
Feedstock purchased [Member] | ||||
Related Party Transaction [Line Items] | ||||
Charges from related parties in cost of sales | 89,599 | 119,925 | 211,754 | 225,340 |
Other service charges [Member] | ||||
Related Party Transaction [Line Items] | ||||
Charges from related parties in cost of sales | $ 27,464 | $ 26,537 | $ 55,036 | $ 54,943 |
Related Party Transactions (Ser
Related Party Transactions (Services from Related Parties Included in SG&A Expenses) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Affiliated Entity [Member] | Westlake [Member] | ||||
Related Party Transaction [Line Items] | ||||
Services received from Westlake and included in selling, general and administrative expenses | $ 6,464 | $ 7,041 | $ 13,067 | $ 13,292 |
Related Party Transactions (Goo
Related Party Transactions (Goods and Services Purchased from Westlake and Capitalized as Assets) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Affiliated Entity [Member] | Westlake [Member] | ||||
Related Party Transaction [Line Items] | ||||
Goods and services purchased from Westlake and capitalized as assets | $ 641 | $ 791 | $ 1,284 | $ 1,142 |
Related Party Transactions (Acc
Related Party Transactions (Accounts Receivable from and Accounts Payable to Related Parties) (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Related Party Transaction [Line Items] | ||
Receivable under the Investment Management Agreement—Westlake Chemical Corporation (Westlake) | $ 141,327 | $ 148,956 |
Accounts payable—Westlake | 9,996 | 27,477 |
Affiliated Entity [Member] | Westlake [Member] | ||
Related Party Transaction [Line Items] | ||
Accounts receivable—Westlake, current and non-current | $ 38,995 | $ 57,280 |
Related Party Transactions (Gen
Related Party Transactions (General) (Details) - Affiliated Entity [Member] - Westlake [Member] - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | |||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 | |
Related Party Transaction [Line Items] | |||||
Operating Lease, Expense | $ 562 | $ 700 | $ 1,076 | $ 1,018 | |
Interest earned related to the IMA | 1,155 | $ 568 | 1,973 | $ 1,108 | |
Accrued Liabilities [Member] | |||||
Related Party Transaction [Line Items] | |||||
Accrued interest included in receivable under IMA | $ 371 | $ 371 | $ 496 |
Related Party Transactions (Deb
Related Party Transactions (Debt Payable to Related Parties) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | |||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 | |
Related Party Transaction [Line Items] | |||||
Interest on related party debt payable | $ 5,125 | $ 5,547 | $ 11,025 | $ 10,413 | |
Accrued interest on related party debt | 5,384 | 5,384 | $ 5,448 | ||
Long-term debt payable to Westlake | 399,674 | 399,674 | 477,608 | ||
Affiliated Entity [Member] | Westlake [Member] | |||||
Related Party Transaction [Line Items] | |||||
Interest capitalized | 0 | 31 | 0 | 46 | |
Other income (expense) [Member] | Affiliated Entity [Member] | Westlake [Member] | |||||
Related Party Transaction [Line Items] | |||||
Interest on related party debt payable | 5,125 | $ 5,547 | 11,025 | $ 10,413 | |
Accrued Liabilities [Member] | Affiliated Entity [Member] | Westlake [Member] | |||||
Related Party Transaction [Line Items] | |||||
Accrued interest on related party debt | $ 5,384 | $ 5,384 | $ 5,448 |
Related Party Transactions (Sit
Related Party Transactions (Site Lease Agreements) (Details) | 6 Months Ended |
Jun. 30, 2019USD ($) | |
Related Party Transaction [Line Items] | |
Site lease agreement, number | 2 |
Site lease agreements, term (in years) | 50 |
Site lease agreements, OpCo annual obligation to WLK | $ 1 |
Related Party Transactions (Maj
Related Party Transactions (Major Customer and Concentration Risk) (Details) | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Affiliated Entity [Member] | Westlake [Member] | Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | ||||
Concentration Risk [Line Items] | ||||
Concentration Risk, Percentage | 85.20% | 84.00% | 85.60% | 83.40% |
Long-term Debt Payable to Wes_3
Long-term Debt Payable to Westlake (Details) - USD ($) $ in Thousands | Mar. 29, 2019 | Sep. 29, 2017 | Apr. 01, 2015 | Apr. 30, 2019 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 |
Related Party Transaction [Line Items] | |||||||
Long-term debt payable to Westlake | $ 399,674 | $ 477,608 | |||||
Repayments of debt | $ 201,445 | ||||||
Proceeds from debt payable to Westlake | $ 123,511 | $ 3,648 | |||||
Weighted average interest rate | 4.60% | 4.40% | |||||
Limited Partner [Member] | OpCo Revolver [Member] | Senior Unsecured Revolving Credit Facility [Member] | |||||||
Related Party Transaction [Line Items] | |||||||
Long-term debt payable to Westlake | $ 22,619 | $ 224,064 | |||||
Limited Partner [Member] | OpCo Revolver [Member] | Senior Unsecured Revolving Credit Facility [Member] | LIBOR [Member] | |||||||
Related Party Transaction [Line Items] | |||||||
Basis spread on variable rate, percent | 2.00% | 2.00% | |||||
Limited Partner [Member] | MLP Revolver [Member] | Senior Unsecured Revolving Credit Facility [Member] | |||||||
Related Party Transaction [Line Items] | |||||||
Long-term debt payable to Westlake | $ 377,055 | $ 253,544 | |||||
Limited Partner [Member] | MLP Revolver [Member] | Senior Unsecured Revolving Credit Facility [Member] | LIBOR [Member] | |||||||
Related Party Transaction [Line Items] | |||||||
Basis spread on variable rate, percent | 2.00% | 2.00% | |||||
Westlake Chemical OpCo LP [Member] | Affiliated Entity [Member] | |||||||
Related Party Transaction [Line Items] | |||||||
Proceeds from debt payable to Westlake | $ 123,512 | ||||||
Limited partner interest, additional ownership | 4.50% | 5.00% | 2.70% |
Fair Value Measurements (Summar
Fair Value Measurements (Summary of Carrying and Fair Values of Long Term Debt) (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
Long-term debt payable to Westlake, carrying value | $ 399,674 | $ 477,608 |
OpCo Revolver [Member] | Senior Unsecured Revolving Credit Facility [Member] | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
Long-term debt payable to Westlake, fair value | 23,072 | 221,002 |
OpCo Revolver [Member] | Senior Unsecured Revolving Credit Facility [Member] | Limited Partner [Member] | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
Long-term debt payable to Westlake, carrying value | 22,619 | 224,064 |
MLP Revolver [Member] | Senior Unsecured Revolving Credit Facility [Member] | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
Long-term debt payable to Westlake, fair value | 377,862 | 249,747 |
MLP Revolver [Member] | Senior Unsecured Revolving Credit Facility [Member] | Limited Partner [Member] | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
Long-term debt payable to Westlake, carrying value | $ 377,055 | $ 253,544 |
Supplemental Information (Detai
Supplemental Information (Details) - USD ($) $ in Thousands | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 | |
Accrued Liabilities [Abstract] | |||
Accrued and other liabilities | $ 18,287 | $ 16,250 | |
Accrued interest | 5,384 | 5,448 | |
Accrued maintenance | 2,451 | 2,688 | |
Accrued Income Taxes | 3,975 | 1,564 | |
Accrued Capital Expenditures, Current | 2,057 | $ 2,818 | |
Increase (reduction) in capital expenditure accrual | $ 567 | $ 5,042 |