Blueknight Energy Partners (BKEP) 10-Q9 May 192019 Q1 Quarterly reportFinancial data

Company Profile

Document And Entity Information

Document And Entity Information - shares	3 Months Ended
Document And Entity Information - shares	Mar. 31, 2019	May 06, 2019	Dec. 31, 2018
Entity Information [Line Items]
Series A Preferred unitholders, units outstanding	35,125,202		35,125,202
Entity Registrant Name	Blueknight Energy Partners, L.P.
Entity Central Index Key	0001392091
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019
Entity Common Stock, Shares Outstanding		40,714,857
Subsequent Event [Member]
Entity Information [Line Items]
Series A Preferred unitholders, units outstanding		35,125,202

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 1,209	$ 1,455
Accounts receivable, net	28,561	35,683
Receivables from related parties, net	936	1,043
Other current assets	7,127	9,345
Total current assets	37,833	47,526
Assets, Noncurrent [Abstract]
Property, plant and equipment, net of accumulated depreciation of $263,554 and $268,753 at December 31, 2018, and March 31, 2019, respectively	243,063	248,261
Goodwill	6,728	6,728
Debt issuance costs, net	3,098	3,349
Operating Lease, Right-of-Use Asset	11,594	0
Intangible assets, net	16,147	16,834
Other noncurrent assets	1,193	606
Total assets	319,656	323,304
Current liabilities:
Accounts payable	3,925	3,707
Accounts payable to related parties	2,111	2,263
Accrued crude oil purchases	7,576	13,949
Accrued crude oil purchases to related parties	11,885	10,219
Accrued interest payable	294	465
Accrued property taxes payable	2,237	3,089
Unearned revenue	3,536	3,206
Unearned revenue with related parties	15,168	4,835
Accrued payroll	2,129	3,667
Current operating lease liability	2,768	0
Other current liabilities	3,042	3,465
Total current liabilities	54,671	48,865
Long-term unearned revenue with related parties	1,612	1,714
Other long-term liabilities	3,715	4,010
Noncurrent operating lease liability	8,935	0
Contingent liability with related party (Note 10)	10,870	10,019
Long-term debt	252,592	265,592
Commitments and contingencies (Note 16)
Partners’ capital:
Common unitholders (40,424,372 and 40,714,857 units issued and outstanding at December 31, 2018, and March 31, 2019, respectively)	365,220	370,972
Preferred Units (35,125,202 units issued and outstanding at both dates)	253,923	253,923
General partner interest (1.6% interest with 1,225,409 general partner units outstanding at both dates)	(631,882)	(631,791)
Total partners’ capital	(12,739)	(6,896)
Total liabilities and partners’ capital	$ 319,656	$ 323,304

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Assets, Noncurrent [Abstract]
Accumulated depreciation	$ 268,576	$ 263,554
Partners’ capital:
Common unitholders, units issued	40,714,857	40,424,372
Common unitholders, units outstanding	40,714,857	40,424,372
Series A Preferred unitholders, units issued	35,125,202	35,125,202
Series A Preferred unitholders, units outstanding	35,125,202	35,125,202
General partner interest, units outstanding	1,225,409	1,225,409
General partner percentage interest	1.60%	1.60%

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Service revenue:
Third-party revenue	$ 15,886	$ 17,318
Related-party revenue	4,219	6,321
Lease revenue:
Third-party revenue	9,763	9,804
Related-party revenue	4,940	7,703
Product sales revenue:
Third-party revenue	58,924	3,514
Total revenue	93,732	44,660
Costs and expenses:
Operating expense	27,243	31,135
Cost of product sales from related party	24,587	2,637
Cost of product sales	30,774	0
General and administrative expense	3,693	4,221
Asset impairment expense	1,119	616
Total costs and expenses	87,416	38,609
Gain (loss) on sale of assets	1,724	(236)
Operating income	8,040	5,815
Other income (expenses):
Gain on sale of unconsolidated affiliate	0	2,225
Interest expense	(4,271)	(3,569)
Income before income taxes	3,769	4,471
Provision for income taxes	12	29
Net income	3,757	4,442
Allocation of net income for calculation of earnings per unit:
General partner interest in net income	105	231
Preferred interest in net income	6,279	6,278
Net income (loss) available to limited partners	$ (2,627)	$ (2,067)
Basic and diluted net income (loss) per common unit	$ (0.06)	$ (0.05)
Weighted average common units outstanding - basic and diluted	40,678	40,289

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN PARTNERS' CAPITAL - USD ($) $ in Thousands	Total	Limited Partner [Member]	General Partner [Member]	Preferred Partner [Member]
Balance at Dec. 31, 2017	$ 4,684	$ 454,358	$ (703,597)	$ 253,923
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	4,442	(2,065)	228	6,279
Equity-based incentive compensation	41	33	8
Distributions	(12,587)	(5,947)	(361)	(6,279)
Capital contributions	183		183
Proceeds from sale of common units pursuant to the Employee Unit Purchase Plan	92	92
Balance at Mar. 31, 2018	(3,145)	446,471	(703,539)	253,923
Balance at Dec. 31, 2018	(6,896)	370,972	(631,791)	253,923
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	3,757	(2,581)	59	6,279
Equity-based incentive compensation	69	64	5
Distributions	(9,742)	(3,308)	(155)	(6,279)
Proceeds from sale of common units pursuant to the Employee Unit Purchase Plan	73	73
Balance at Mar. 31, 2019	$ (12,739)	$ 365,220	$ (631,882)	$ 253,923

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN PARTNERS' CAPITAL CONSOLIDATED STATEMENTS OF CHANGES IN PARTNERS' CAPITAL (Parenthetical) - shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Changes in Partners Capital [Abstract]
Units Issued, Unit Based Compensation	63,340	21,246

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities:
Net income	$ 3,757	$ 4,442
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for uncollectible receivables from third parties	0	8
Depreciation and amortization	6,734	7,367
Amortization of debt issuance costs	251	256
Unrealized (gain) loss related to interest rate swaps	44	(354)
Intangible asset impairment charge	0	189
Fixed asset impairment charge	1,119	427
Loss (gain) on sale of assets	(1,724)	236
Gain on sale of unconsolidated affiliate	0	(2,225)
Equity-based incentive compensation	69	41
Changes in assets and liabilities:
Decrease (increase) in accounts receivable	4,480	(2,811)
Decrease in receivables from related parties	107	960
Decrease (increase) in other current assets	2,613	399
Decrease in other non-current assets	803	41
Decrease in accounts payable	(297)	(154)
Increase (decrease) in payables to related parties	(315)	625
Decrease in accrued crude oil purchases	(6,373)	0
Increase in accrued crude oil purchases to related parties	1,666	0
Increase (decrease) in accrued interest payable	(171)	24
Decrease in accrued property taxes	(852)	(80)
Increase in unearned revenue	165	637
Increase in unearned revenue from related parties	10,231	3,655
Decrease in accrued payroll	(1,538)	(3,323)
Decrease in other accrued liabilities	(1,252)	(419)
Net cash provided by operating activities	19,517	9,941
Cash flows from investing activities:
Acquisitions	0	(21,959)
Capital expenditures	(2,801)	(4,563)
Proceeds from sale of assets	6,304	26
Proceeds from sale of unconsolidated affiliate	0	2,225
Net cash provided by (used in) investing activities	3,503	(24,271)
Cash flows from financing activities:
Payments on other financing activities	(597)	(746)
Borrowings under credit agreement	75,000	54,000
Payments under credit agreement	88,000	27,000
Proceeds from equity issuance	73	92
Capital contributions	0	183
Distributions	(9,742)	(12,587)
Net cash provided by (used in) financing activities	(23,266)	13,942
Net decrease in cash and cash equivalents	(246)	(388)
Cash and cash equivalents at beginning of period	1,455	2,469
Cash and cash equivalents at end of period	1,209	2,081
Supplemental disclosure of non-cash financing and investing cash flow information:
Non-cash changes in property, plant and equipment	711	1,251
Increase in accrued liabilities related to insurance premium financing agreement	$ 751	$ 720

ORGANIZATION AND NATURE OF BUSI

ORGANIZATION AND NATURE OF BUSINESS	3 Months Ended
ORGANIZATION AND NATURE OF BUSINESS	Mar. 31, 2019
ORGANIZATION AND NATURE OF BUSINESS [Abstract]
ORGANIZATION AND NATURE OF BUSINESS	ORGANIZATION AND NATURE OF BUSINESS Blueknight Energy Partners, L.P. and subsidiaries (collectively, the “Partnership”) is a publicly traded master limited partnership with operations in 27 states. The Partnership provides integrated terminalling, gathering, transportation and marketing services for companies engaged in the production, distribution and marketing of crude oil and asphalt products. The Partnership manages its operations through four operating segments: (i) asphalt terminalling services, (ii) crude oil terminalling services, (iii) crude oil pipeline services and (iv) crude oil trucking services. The Partnership’s common units and preferred units, which represent limited partnership interests in the Partnership, are listed on the NASDAQ Global Market under the symbols “BKEP” and “BKEPP,” respectively. The Partnership was formed in February 2007 as a Delaware master limited partnership initially to own, operate and develop a diversified portfolio of complementary midstream energy assets.

BASIS OF CONSOLIDATION AND PRES

BASIS OF CONSOLIDATION AND PRESENTATION	3 Months Ended
BASIS OF CONSOLIDATION AND PRESENTATION	Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
BASIS OF CONSOLIDATION AND PRESENTATION	BASIS OF CONSOLIDATION AND PRESENTATION The financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”). The condensed consolidated balance sheet as of March 31, 2019 , the condensed consolidated statements of operations for the three months ended March 31, 2018 and 2019 , the condensed consolidated statements of changes in partners’ capital (deficit) for the three months ended March 31, 2018 and 2019 , and the condensed consolidated statements of cash flows for the three months ended March 31, 2018 and 2019 , are unaudited. In the opinion of management, the unaudited condensed consolidated financial statements have been prepared on the same basis as the audited financial statements and include all adjustments necessary to state fairly the financial position and results of operations for the respective interim periods. All adjustments are of a recurring nature unless otherwise disclosed herein. The 2018 year-end condensed consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by GAAP. These unaudited condensed consolidated financial statements and notes should be read in conjunction with the consolidated financial statements and notes thereto included in the Partnership’s annual report on Form 10-K for the year ended December 31, 2018 , filed with the Securities and Exchange Commission (the “SEC”) on March 12, 2019 (the “ 2018 Form 10-K”). Interim financial results are not necessarily indicative of the results to be expected for an annual period. The Partnership’s significant accounting policies are consistent with those disclosed in Note 3 of the Notes to Consolidated Financial Statements in its 2018 Form 10-K. Certain reclassifications have been made in the consolidated balance sheet as of December 31, 2018 , and the consolidated statement of cash flows for the three months ended March 31, 2018, to conform to the 2019 financial statement presentation. These reclassifications relate to items included in “Other current assets” and “Other noncurrent assets.” Reclassifications on the consolidated statement of cash flows were limited to the “Cash flows from operating activities” section. The reclassifications have no impact on net income.

REVENUE REVENUE

REVENUE REVENUE	3 Months Ended
REVENUE REVENUE	Mar. 31, 2019
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers [Text Block]	REVENUE On January 1, 2019, the Partnership adopted the new accounting standard ASC 842 - Leases and all related amendments (“new lease standard”) using the modified retrospective method. Results for reporting periods beginning on January 1, 2019, are presented under the new lease standard, while prior period amounts are not adjusted and continue to be reported in accordance with the Partnership’s historic accounting under ASC 840 - Leases . The adoption of ASC 842 did not have a material effect on the Partnership’s revenue recognition. The primary impact is a change to the recognition of variable consideration that has both a service and lease component. Previously, the variable consideration related to the service component was estimated at the beginning of the contract year and recognized on a straight-line basis over the year. Under ASC 842, the variable consideration related to the service component is treated as a change in estimate in the period when the facts and circumstances on which the variable payment is based occur. There are two types of contracts in the asphalt terminalling segment: (i) operating lease contracts, under which customers operate the facilities, and (ii) storage, throughput and handling contracts, under which the Partnership operates the facilities. The operating lease contracts are accounted for in accordance with ASC 842 - Leases. The storage, throughput and handling contracts contain both lease revenue and non-lease service revenue. In accordance with ASC 842 and 606, fixed consideration is allocated to the lease and service components based on their relative stand-alone selling price. The stand-alone selling price of the lease component is calculated using the average internal rate of return under the operating lease agreements. The stand-alone selling price of the service component is calculated by applying an appropriate margin to the expected costs to operate the facility. The service component contains a single performance obligation that consists of a stand-ready obligation to perform activities as directed by the customer, and revenue is recognized on a straight-line basis over time as the customer receives and consumes benefits. The lease component is recognized on a straight-line basis over the term of the initial lease. Fixed consideration, consisting of the monthly storage and handling fees, is billed a month prior to the performance of services and is due by the first day of the month of service. Payments received in advance of the month of service are recorded as unearned revenue until the service is performed, and the service component is treated as a contract liability. Asphalt storage, throughput and handling contracts also contain variable consideration in the form of reimbursements of utility, fuel and power expenses and throughput fees. Utility, fuel and power reimbursements are allocated entirely to the service component of the contracts. Utility, fuel and power reimbursements relate directly to the distinct monthly service that makes up the overall performance obligation and revenue is recognized in the period in which the service takes place. Variable consideration related to reimbursements of utility, fuel and power expenses is billed in the month subsequent to the period of service, and payment is due within 30 days of billing. Throughput fees are allocated to both the lease and service component of the contracts using the allocation percentages from contract inception. In accordance with ASC 842, the lease component of variable throughput fees is recognized in the period when the changes in facts and circumstances on which the variable payment is based occur. Additionally, under ASC 842, when variable consideration contains both a lease and non-lease service component, the service component cannot be recognized until the period in which the changes in facts and circumstances on which the variable payment is based occur. At that time, it can be recognized in accordance with ASC 606. The service component of variable throughput fees is treated as a change in estimate in the period in when the changes in facts and circumstances on which the variable payment is based occur and is then recognized on a straight-line basis over time as the customer receives and consumes benefits. Payment on variable throughput consideration is due within 30 days of billing. Certain asphalt storage, throughput and handling contracts contain provisions for reimbursement of specified major maintenance costs above a specified threshold over the life of the contract. Reimbursements of specified major maintenance costs are allocated to both the lease and service component of the contracts using the allocation percentages from contract inception. Reimbursements of specified major maintenance costs are reviewed and paid quarterly, which may result in overpayments that must be paid back to the customer in future years. As such, the service component of this consideration is constrained and recorded in unearned revenue (contract liability) until facts and circumstances indicate it is probable that the minimum threshold will be met. In the event the minimum threshold is not met, the Partnership will return the reimbursement to the customer. As of March 31, 2019 , the Partnership has service revenue performance obligations satisfied over time under asphalt storage, throughput and handling contracts that are wholly or partially unsatisfied. The service revenue related to these performance obligations will be recognized as follows (in thousands): Revenue Related to Future Performance Obligations Due by Period (1) Twelve months ending March 31, 2020 $ 30,705 Twelve months ending March 31, 2021 29,704 Twelve months ending March 31, 2022 25,487 Twelve months ending March 31, 2023 18,903 Twelve months ending March 31, 2024 11,711 Thereafter 7,841 Total revenue related to future performance obligations $ 124,351 ____________________ (1) Excluded from the table is revenue that is either constrained or related to performance obligations that are wholly unsatisfied as of March 31, 2019 . In addition, as of March 31, 2019 , the Partnership has minimum future annual lease rentals contracted to be received under asphalt operating lease contracts and asphalt storage, throughput and handling contracts. The lease revenue related to these minimum rentals will be recognized as follows (in thousands): Revenue Related to Minimum Future Annual Lease Rentals Due by Period Twelve months ending March 31, 2020 $ 55,176 Twelve months ending March 31, 2021 52,360 Twelve months ending March 31, 2022 46,637 Twelve months ending March 31, 2023 36,655 Twelve months ending March 31, 2024 24,798 Thereafter 19,220 Total revenue related to minimum future annual lease rentals $ 234,846 Crude oil terminalling services contracts can be either short- or long-term written contracts. The contracts contain a single performance obligation that consists of a series of distinct services provided over time. Customers are billed a month prior to the performance of terminalling services and payment is due by the first day of the month of service. Payments received in advance of the month of service are recorded as unearned revenue (contract liability) until the service is performed. These contracts also contain provisions under which customers are invoiced for product throughput in the month following the month in which the service is provided. Payment on product throughput is due within 30 days . The Partnership has elected to use the right-to-invoice expedient on crude oil terminalling services contracts as the right to consideration corresponds directly with the value to the customer of performance completed to date. There are primarily two types of contracts in the crude oil pipeline segment: (i) monthly transportation contracts and (ii) product sales contracts. Under crude oil pipeline services monthly transportation contracts, customers submit nominations for transportation monthly and a contract is created upon the Partnership’s acceptance of the nomination under its published tariffs. Crude oil pipeline services contracts have a single performance obligation to perform the transportation service. The transportation service is provided to the customer in the same month in which the customer makes the related nomination. Revenue is recorded in the month of service and invoiced in the following month. Payment is due within 30 days . The Partnership has elected to use the right-to-invoice expedient on crude oil pipeline services contracts as the right to consideration corresponds directly with the value to the customer of performance completed to date. The Partnership also purchases crude oil and resells to third parties under written product sales contracts. Product sales contracts have a single performance obligation, and revenue is recognized at the point in time that control is transferred to the customer. Control is considered transferred to the customer on the day of the sale. Revenue is recorded in the month of service and invoiced in the following month. Payment is due within 30 days . The Partnership has elected to use the right-to-invoice expedient on product sales contracts as the right to consideration corresponds directly with the value to the customer of performance completed to date. Services in the crude oil trucking segment are provided under master service agreements with customers that include rate sheets. Contracts are initiated when a customer requests service and both parties are committed upon the Partnership’s acceptance of the customer’s request. Crude oil trucking contracts have a single performance obligation to perform the service, which is completed in a day. Revenue is recorded in the month of service and invoiced in the following month. Payment is due within 30 days . The Partnership has elected to use the right-to-invoice expedient on crude oil trucking revenues as the right to consideration corresponds directly with the value to the customer of performance completed to date. Disaggregation of Revenue Disaggregation of revenue from contracts with customers for each operating segment by revenue type is presented as follows (in thousands): Three Months ended March 31, 2018 Asphalt Terminalling Services Crude Oil Terminalling Services Crude Oil Pipeline Services Crude Oil Trucking Services Total Third-party revenue: Fixed storage, throughput and other revenue $ 3,549 $ 4,081 $ — $ — $ 7,630 Variable throughput revenue 117 504 — — 621 Variable reimbursement revenue 1,466 — — — 1,466 Crude oil transportation revenue — — 2,061 5,540 7,601 Crude oil product sales revenue — — 3,508 6 3,514 Related-party revenue: Fixed storage, throughput and other revenue 4,631 — — — 4,631 Variable reimbursement revenue 1,690 — — — 1,690 Total revenue from contracts with customers $ 11,453 $ 4,585 $ 5,569 $ 5,546 $ 27,153 Three Months ended March 31, 2019 Asphalt Terminalling Services Crude Oil Terminalling Services Crude Oil Pipeline Services Crude Oil Trucking Services Total Third-party revenue: Fixed storage, throughput and other revenue $ 4,983 $ 3,069 $ — $ — $ 8,052 Variable throughput revenue 3 504 — — 507 Variable reimbursement revenue 1,996 — — — 1,996 Crude oil transportation revenue — — 2,498 2,833 5,331 Crude oil product sales revenue — — 58,924 — 58,924 Related-party revenue: Fixed storage, throughput and other revenue 2,848 — 83 — 2,931 Variable reimbursement revenue 1,270 — 18 — 1,288 Total revenue from contracts with customers $ 11,100 $ 3,573 $ 61,523 $ 2,833 $ 79,029 Contract Balances The timing of revenue recognition, billings and cash collections result in billed accounts receivable and unearned revenue (contract liabilities) on the unaudited condensed consolidated balance sheets as noted in the contract discussions above. Accounts receivable are reflected in the line items “Accounts receivable” and “Receivables from related parties” on the unaudited condensed consolidated balance sheets. Unearned revenue is included in the line items “Unearned revenue,” “Unearned revenue with related parties,” “Long-term unearned revenue with related parties” and “Other long-term liabilities” on the unaudited condensed consolidated balance sheets. Billed accounts receivable from contracts with customers were $34.6 million and $25.8 million at December 31, 2018 , and March 31, 2019 , respectively. The Partnership records unearned revenues when cash payments are received in advance of performance. Unearned revenue related to contracts with customers was $5.9 million and $10.1 million at December 31, 2018 , and March 31, 2019 , respectively. The change in the unearned revenue balance for the three months ended March 31, 2019 , is driven by $7.3 million in cash payments received in advance of satisfying performance obligations, partially offset by $3.1 million of revenues recognized that were included in the unearned revenue balance at the beginning of the period. Practical Expedients and Exemptions The Partnership does not disclose the value of unsatisfied performance obligations for (i) contracts with an original expected length of one year or less and (ii) contracts for which revenue is recognized at the amount to which the Partnership has the right to invoice for services performed. The Partnership is using the right-to-invoice practical expedient on all contracts with customers in its crude oil terminalling services, crude oil pipeline services and crude oil trucking services segments.

RESTRUCTURING CHARGES RESTRUCTU

RESTRUCTURING CHARGES RESTRUCTURING CHARGES	3 Months Ended
RESTRUCTURING CHARGES RESTRUCTURING CHARGES	Mar. 31, 2019
Restructuring and Related Activities [Abstract]
Restructuring and Related Activities Disclosure [Text Block]	RESTRUCTURING CHARGES During the fourth quarter of 2015, the Partnership recognized certain restructuring charges in its crude oil trucking services segment pursuant to an approved plan to exit the trucking market in West Texas. The restructuring charges included an accrual related to leased vehicles that were idled as part of the restructuring plan. This accrual was being amortized over the remaining lease term of the vehicles. In June 2018, the Partnership purchased the vehicles off lease and resold them to a third party, paying off the remaining liability. Changes in the accrued amounts pertaining to the restructuring charges are summarized as follows (in thousands): Three Months ended 2018 Beginning balance $ 286 Cash payments 49 Ending balance $ 237

EQUITY METHOD INVESTMENT EQUITY

EQUITY METHOD INVESTMENT EQUITY METHOD INVESTMENT	3 Months Ended
EQUITY METHOD INVESTMENT EQUITY METHOD INVESTMENT	Mar. 31, 2019
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments and Joint Ventures Disclosure [Text Block]	EQUITY METHOD INVESTMENT The Partnership’s investment in Advantage Pipeline, L.L.C. (“Advantage Pipeline”), over which the Partnership had significant influence but not control, was accounted for by the equity method. The Partnership did not consolidate any part of the assets or liabilities of Advantage Pipeline. On April 3, 2017, Advantage Pipeline was acquired by a joint venture formed by affiliates of Plains All American Pipeline, L.P. and Noble Midstream Partners LP. The Partnership received cash proceeds at closing from the sale of its approximate 30% equity ownership interest in Advantage Pipeline of approximately $25.3 million and recorded a gain on the sale of the investment of $4.2 million . Approximately 10% of the gross sale proceeds were held in escrow, subject to certain post-closing settlement terms and conditions. The Partnership received approximately $1.1 million of the funds held in escrow in August 2017, and approximately $2.2 million for its pro rata portion of the remaining net escrow proceeds in January 2018. The Partnership’s proceeds were used to prepay revolving debt (without a commitment reduction). As of March 31, 2019 , the Partnership had no equity investments.

PROPERTY, PLANT AND EQUIPMENT

PROPERTY, PLANT AND EQUIPMENT	3 Months Ended
PROPERTY, PLANT AND EQUIPMENT	Mar. 31, 2019
Property, Plant and Equipment [Abstract]
PROPERTY, PLANT AND EQUIPMENT	PROPERTY, PLANT AND EQUIPMENT Estimated Useful Lives (Years) December 31, 2018 March 31, (dollars in thousands) Land N/A $ 24,705 $ 24,705 Land improvements 10-20 5,758 5,798 Pipelines and facilities 5-30 116,155 117,188 Storage and terminal facilities 10-35 321,096 322,476 Transportation equipment 3-10 2,798 1,782 Office property and equipment and other 3-20 26,980 27,186 Pipeline linefill and tank bottoms N/A 10,297 8,882 Construction-in-progress N/A 4,026 3,622 Property, plant and equipment, gross 511,815 511,639 Accumulated depreciation (263,554 ) (268,576 ) Property, plant and equipment, net $ 248,261 $ 243,063 Plant, property and equipment under operating leases at March 31, 2019 , in which the Partnership is the lessor, had a cost basis of $282.1 million and accumulated depreciation of $173.3 million . Depreciation expense for the three months ended March 31, 2018 and 2019 , was $7.0 million and $6.0 million , respectively. During the three months ended March 31, 2019 , the Partnership recognized asset impairment expense of $1.1 million . A change in estimate of the push-down impairment related to Cimarron Express Pipeline, LLC (“Cimarron Express”) resulted in additional impairment expense of $0.8 million . This impairment is recorded at the corporate level and the estimate is based on the expected amount due to Ergon if the Put (as defined in Note 10) is exercised (see Note 10 for more information). In addition, a flood at an asphalt terminal in Wolcott, Kansas, led to an impairment of $0.3 million . During the three months ended March 31, 2019 , the Partnership sold various surplus assets, including the sale of three truck stations for $1.6 million , which resulted in a gain of $1.5 million , and the sale of pipeline linefill for $1.6 million , which resulted in a gain of $0.2 million . In addition, proceeds received during the three months ended March 31, 2019 , included $2.6 million related to a sale of pipeline linefill in December 2018, for which the proceeds were received in January 2019. On July 12, 2018, the Partnership sold certain asphalt terminals, storage tanks and related real property, contracts, permits, assets and other interests located in Lubbock and Saginaw, Texas and Memphis, Tennessee (the “Divestiture”) to Ergon Asphalt & Emulsion, Inc. for a purchase price of $90.0 million , subject to customary adjustments. The Divestiture does not qualify as discontinued operations as it does not represent a strategic shift that will have a major effect on the Partnership’s operations or financial results. The Partnership used the proceeds from the sale to prepay revolving debt under its credit agreement. In April 2018, the Partnership sold its producer field services business. The Partnership received cash proceeds at closing of approximately $3.0 million and recorded a gain of $0.4 million . The sale of the producer field services business does not qualify as discontinued operations as it does not represent a strategic shift that will have a major effect on the Partnership’s operations or financial results. The Partnership used the proceeds from the sale to prepay revolving debt under its credit agreement. In March 2018, the Partnership acquired an asphalt terminalling facility in Oklahoma from a third party for approximately $22.0 million , consisting of property, plant and equipment of $11.5 million , intangible assets of $7.6 million and goodwill of $2.9 million .

DEBT

DEBT	3 Months Ended
DEBT	Mar. 31, 2019
Debt Disclosure [Abstract]
DEBT	DEBT On May 11, 2017, the Partnership entered into an amended and restated credit agreement. On June 28, 2018, the credit agreement was amended to, among other things, reduce the revolving loan facility from $450.0 million to $400.0 million and amend the maximum permitted consolidated total leverage ratio as discussed below. As of May 6, 2019 , approximately $251.6 million of revolver borrowings and $1.0 million of letters of credit were outstanding under the credit agreement, leaving the Partnership with approximately $147.4 million available capacity for additional revolver borrowings and letters of credit under the credit agreement, although the Partnership’s ability to borrow such funds may be limited by the financial covenants in the credit agreement. The proceeds of loans made under the credit agreement may be used for working capital and other general corporate purposes of the Partnership. The credit agreement is guaranteed by all of the Partnership’s existing subsidiaries. Obligations under the credit agreement are secured by first priority liens on substantially all of the Partnership’s assets and those of the guarantors. The credit agreement includes procedures for additional financial institutions to become revolving lenders, or for any existing lender to increase its revolving commitment thereunder, subject to an aggregate maximum of $600.0 million for all revolving loan commitments under the credit agreement. The credit agreement will mature on May 11, 2022 , and all amounts outstanding under the credit agreement will become due and payable on such date. The credit agreement requires mandatory prepayments of amounts outstanding thereunder with the net proceeds of certain asset sales, property or casualty insurance claims and condemnation proceedings, unless the Partnership reinvests such proceeds in accordance with the credit agreement, but these mandatory prepayments will not require any reduction of the lenders’ commitments under the credit agreement. Borrowings under the credit agreement bear interest, at the Partnership’s option, at either the reserve-adjusted eurodollar rate (as defined in the credit agreement) plus an applicable margin that ranges from 2.0% to 3.25% or the alternate base rate (the highest of the agent bank’s prime rate, the federal funds effective rate plus 0.5% , and the 30-day eurodollar rate plus 1.0% ) plus an applicable margin that ranges from 1.0% to 2.25% . The Partnership pays a per annum fee on all letters of credit issued under the credit agreement, which fee equals the applicable margin for loans accruing interest based on the eurodollar rate, and the Partnership pays a commitment fee ranging from 0.375% to 0.5% on the unused commitments under the credit agreement. The applicable margins for the Partnership’s interest rate, the letter of credit fee and the commitment fee vary quarterly based on the Partnership’s consolidated total leverage ratio (as defined in the credit agreement, being generally computed as the ratio of consolidated total debt to consolidated earnings before interest, taxes, depreciation, amortization and certain other non-cash charges). The credit agreement includes financial covenants that are tested on a quarterly basis, based on the rolling four-quarter period that ends on the last day of each fiscal quarter. Prior to the date on which the Partnership issues qualified senior notes in an aggregate principal amount (when combined with all other qualified senior notes previously or concurrently issued) that equals or exceeds $200.0 million , the maximum permitted consolidated total leverage ratio will be 5.25 to 1.00 for the fiscal quarters ending March 31, 2019, and June 30, 2019; 5.00 to 1.00 for the fiscal quarters ending September 30, 2019, and December 31, 2019; and 4.75 to 1.00 for the fiscal quarter ending March 31, 2020, and each fiscal quarter thereafter; provided that the maximum permitted consolidated total leverage ratio may be increased to 5.25 to 1.00 for certain quarters after December 31, 2019, based on the occurrence of a specified acquisition (as defined in the credit agreement, but generally being an acquisition for which the aggregate consideration is $15.0 million or more). From and after the date on which the Partnership issues qualified senior notes in an aggregate principal amount (when combined with all other qualified senior notes previously or concurrently issued) that equals or exceeds $200.0 million , the maximum permitted consolidated total leverage ratio is 5.00 to 1.00; provided that from and after the fiscal quarter ending immediately preceding the fiscal quarter in which a specified acquisition occurs to and including the last day of the second full fiscal quarter following the fiscal quarter in which such acquisition occurred, the maximum permitted consolidated total leverage ratio will be 5.50 to 1.00. The maximum permitted consolidated senior secured leverage ratio (as defined in the credit agreement, but generally computed as the ratio of consolidated total secured debt to consolidated earnings before interest, taxes, depreciation, amortization and certain other non-cash charges) is 3.50 to 1.00, but this covenant is only tested from and after the date on which the Partnership issues qualified senior notes in an aggregate principal amount (when combined with all other qualified senior notes previously or concurrently issued) that equals or exceeds $200.0 million . The minimum permitted consolidated interest coverage ratio (as defined in the credit agreement, but generally computed as the ratio of consolidated earnings before interest, taxes, depreciation, amortization and certain other non-cash charges to consolidated interest expense) is 2.50 to 1.00. In addition, the credit agreement contains various covenants that, among other restrictions, limit the Partnership’s ability to: • create, issue, incur or assume indebtedness; • create, incur or assume liens; • engage in mergers or acquisitions; • sell, transfer, assign or convey assets; • repurchase the Partnership’s equity, make distributions to unitholders and make certain other restricted payments; • make investments; • modify the terms of certain indebtedness, or prepay certain indebtedness; • engage in transactions with affiliates; • enter into certain hedging contracts; • enter into certain burdensome agreements; • change the nature of the Partnership’s business; and • make certain amendments to the Partnership’s partnership agreement. At March 31, 2019 , the Partnership’s consolidated total leverage ratio was 4.64 to 1.00 and the consolidated interest coverage ratio was 3.42 to 1.00. The Partnership was in compliance with all covenants of its credit agreement as of March 31, 2019 . Management evaluates whether conditions and/or events raise substantial doubt about the Partnership’s ability to continue as a going concern within one year after the date that the consolidated financial statements are issued (the “assessment period”). In performing this assessment, management considered the risk associated with its ongoing ability to meet the financial covenants. Based on the Partnership’s forecasted EBITDA during the assessment period, management believes that it will meet these financial covenants (as described below). However, there are certain inherent risks associated with our continued ability to comply with our consolidated total leverage ratio covenant. These risks relate, among other things, to potential future (a) decreases in storage volumes and rates as well as throughput and transportation rates realized; (b) weather phenomenon that may potentially hinder the Partnership’s asphalt business activity; and (c) other items affecting forecasted levels of expenditures and uses of cash resources. Violation of the consolidated total leverage ratio covenant would be an event of default under the credit agreement, which would cause our $252.6 million in outstanding debt, as of March 31, 2019 , to become immediately due and payable. If this were to occur, the Partnership would not expect to have sufficient liquidity to repay these outstanding amounts then due, which could cause the lenders under the credit facility to pursue other remedies. Such remedies could include exercising their collateral rights to the Partnership’s assets. Based on management’s current forecasts, management believes the Partnership will be able to comply with the consolidated total leverage ratio during the assessment period. However, the Partnership cannot make any assurances that it will be able to achieve management’s forecasts. If the Partnership is unable to achieve management’s forecasts, further actions may be necessary to remain in compliance with the Partnership’s consolidated total leverage ratio covenant including, but not limited to, cost reductions, common and preferred unitholder distribution curtailments, and/or asset sales. The Partnership can make no assurances that it would be successful in undertaking these actions or that the Partnership will remain in compliance with the consolidated total leverage ratio during the assessment period. The credit agreement permits the Partnership to make quarterly distributions of available cash (as defined in the Partnership’s partnership agreement) to unitholders so long as no default or event of default exists under the credit agreement on a pro forma basis after giving effect to such distribution, provided, however, commencing with the fiscal quarter ending September 30, 2018, in no event shall aggregate quarterly distributions in any individual fiscal quarter exceed $10.7 million through, and including, the fiscal quarter ending December 31, 2019. The Partnership is currently allowed to make distributions to its unitholders in accordance with this covenant; however, the Partnership will only make distributions to the extent it has sufficient cash from operations after establishment of cash reserves as determined by the Board of Directors (the “Board”) of Blueknight Energy Partners G.P., L.L.C. (the “general partner”) in accordance with the Partnership’s cash distribution policy, including the establishment of any reserves for the proper conduct of the Partnership’s business. See Note 9 for additional information regarding distributions. In addition to other customary events of default, the credit agreement includes an event of default if: (i) the general partner ceases to own 100% of the Partnership’s general partner interest or ceases to control the Partnership; (ii) Ergon ceases to own and control 50% or more of the membership interests of the general partner; or (iii) during any period of 12 consecutive months, a majority of the members of the Board of the general partner ceases to be composed of individuals: (A) who were members of the Board on the first day of such period; (B) whose election or nomination to the Board was approved by individuals referred to in clause (A) above constituting at the time of such election or nomination at least a majority of the Board; or (C) whose election or nomination to the Board was approved by individuals referred to in clauses (A) and (B) above constituting at the time of such election or nomination at least a majority of the Board, provided that any changes to the composition of individuals serving as members of the Board approved by Ergon will not cause an event of default. If an event of default relating to bankruptcy or other insolvency events occurs with respect to the general partner or the Partnership, all indebtedness under the credit agreement will immediately become due and payable. If any other event of default exists under the credit agreement, the lenders may accelerate the maturity of the obligations outstanding under the credit agreement and exercise other rights and remedies. In addition, if any event of default exists under the credit agreement, the lenders may commence foreclosure or other actions against the collateral. If any default occurs under the credit agreement, or if the Partnership is unable to make any of the representations and warranties in the credit agreement, the Partnership will be unable to borrow funds or to have letters of credit issued under the credit agreement. Debt issuance costs are being amortized over the term of the credit agreement. Interest expense related to debt issuance cost amortization for each of the three months ended March 31, 2018 and 2019 , was $0.3 million . During the three months ended March 31, 2018 and 2019 , the weighted average interest rate under the Partnership’s credit agreement was 4.96% and 6.43% , respectively, resulting in interest expense of approximately $3.9 million and $4.3 million , respectively. The Partnership is exposed to market risk for changes in interest rates related to its credit agreement. Interest rate swap agreements are sometimes used to manage a portion of the exposure related to changing interest rates by converting floating-rate debt to fixed-rate debt. As of March 31, 2019 , the Partnership had no interest rate swap agreements; interest rate swap agreements with notional amounts totaling $100.0 million matured on January 28, 2019. During the three months ended March 31, 2018 and 2019 , the Partnership recorded swap interest expense of $0.1 million and swap interest income of less than $0.1 million , respectively. The interest rate swaps do not receive hedge accounting treatment under ASC 815 - Derivatives and Hedging . The following provides information regarding the Partnership’s assets and liabilities related to its interest rate swap agreements as of the periods indicated (in thousands): Derivatives Not Designated as Hedging Instruments Balance Sheet Location Fair Value of Derivatives December 31, 2018 Interest rate swap assets - current Other current assets $ 44 Changes in the fair value of the interest rate swaps are reflected in the unaudited condensed consolidated statements of operations as follows (in thousands): Derivatives Not Designated as Hedging Instruments Location of Gain (Loss) Recognized in Net Income on Derivatives Amount of Gain (Loss) Recognized in Net Income on Derivatives Three Months ended 2018 2019 Interest rate swaps Interest expense, net of capitalized interest $ 354 $ (44 )

NET INCOME PER LIMITED PARTNER

NET INCOME PER LIMITED PARTNER UNIT	3 Months Ended
NET INCOME PER LIMITED PARTNER UNIT	Mar. 31, 2019
Earnings Per Share [Abstract]
NET INCOME PER LIMITED PARTNER UNIT	NET INCOME PER LIMITED PARTNER UNIT For purposes of calculating earnings per unit, the excess of distributions over earnings or excess of earnings over distributions for each period are allocated to the Partnership’s general partner based on the general partner’s ownership interest at the time. The following sets forth the computation of basic and diluted net income per common unit (in thousands, except per unit data): Three Months ended 2018 2019 Net income $ 4,442 $ 3,757 General partner interest in net income 231 105 Preferred interest in net income 6,278 6,279 Net loss available to limited partners $ (2,067 ) $ (2,627 ) Basic and diluted weighted average number of units: Common units 40,289 40,678 Restricted and phantom units 833 769 Total units 41,122 41,447 Basic and diluted net loss per common unit $ (0.05 ) $ (0.06 )

PARTNERS' CAPITAL AND DISTRIBUT

PARTNERS' CAPITAL AND DISTRIBUTIONS	3 Months Ended
PARTNERS' CAPITAL AND DISTRIBUTIONS	Mar. 31, 2019
Partners' Capital Account, Distributions [Abstract]
PARTNERS' CAPITAL AND DISTRIBUTIONS	PARTNERS’ CAPITAL AND DISTRIBUTIONS On April 22, 2019 , the Partnership announced that the Board approved a cash distribution of $0.17875 per outstanding Preferred Unit for the three months ended March 31, 2019 . The Partnership will pay this distribution on May 14, 2019 , to unitholders of record as of May 3, 2019 . The total distribution will be approximately $6.4 million , with approximately $6.3 million and $0.1 million paid to the Partnership’s preferred unitholders and general partner, respectively. In addition, the Board approved a cash distribution of $0.04 per outstanding common unit for the three months ended March 31, 2019 . The Partnership will pay this distribution on May 14, 2019 , to unitholders of record on May 3, 2019 . The total distribution will be approximately $1.7 million , with approximately $1.6 million and $0.1 million to be paid to the Partnership’s common unitholders and general partner, respectively, and less than $0.1 million to be paid to holders of phantom and restricted units pursuant to awards granted under the Partnership’s Long-Term Incentive Plan.

RELATED PARTY TRANSACTIONS

RELATED PARTY TRANSACTIONS	3 Months Ended
RELATED PARTY TRANSACTIONS	Mar. 31, 2019
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	RELATED-PARTY TRANSACTIONS Transactions with Ergon The Partnership leases asphalt facilities and provides asphalt terminalling services to Ergon. For the three months ended March 31, 2018 and 2019 , the Partnership recognized related-party revenues of $14.0 million and $9.1 million , respectively, for services provided to Ergon. As of December 31, 2018 , and March 31, 2019 , the Partnership had receivables from Ergon of $1.0 million and $0.9 million , respectively, net of allowance for doubtful accounts. As of December 31, 2018 , and March 31, 2019 , the Partnership had unearned revenues from Ergon of $6.5 million and $16.8 million , respectively. Effective April 1, 2018, the Partnership entered into an agreement with Ergon under which the Partnership purchases crude oil in connection with its crude oil marketing operations. For the three months ended March 31, 2019 , the Partnership made purchases of crude oil under this agreement totaling $29.7 million . As of March 31, 2019 , the Partnership had payables to Ergon related to this agreement of $11.9 million related to the March crude oil settlement cycle, and this balance was paid in full on April 19, 2019. The Partnership and Ergon have an agreement (the “Agreement”) that gives each party rights concerning the purchase or sale of Ergon’s interest in Cimarron Express, subject to certain terms and conditions. Cimarron Express was planned to be a new 16-inch diameter, 65-mile crude oil pipeline running from northeastern Kingfisher County, Oklahoma to the Partnership’s Cushing, Oklahoma crude oil terminal, with an originally anticipated in-service date in the second half of 2019. Ergon formed a Delaware limited liability company, Ergon - Oklahoma Pipeline, LLC (“DEVCO”), which holds Ergon’s 50% membership interest in Cimarron Express. Under the Agreement, the Partnership has the right, at any time, to purchase 100% of the authorized and outstanding member interests in DEVCO from Ergon for the Purchase Price (as defined in the Agreement), which shall be computed by taking Ergon’s total investment in the Cimarron Express plus interest, by giving written notice to Ergon (the “Call”). Ergon has the right to require the Partnership to purchase 100% of the authorized and outstanding member interests of DEVCO for the Purchase Price (the “Put”) at any time beginning the earlier of (i) 18 months from the formation, May 9, 2018, of the joint venture company to build the pipeline, (ii) six months after completion of the pipeline, or (iii) the event of dissolution of Cimarron Express. Upon exercise of the Call or the Put, the Partnership and Ergon will execute the Member Interest Purchase Agreement, which is attached to the Agreement as Exhibit B. Upon receipt of the Purchase Price, Ergon shall be obligated to convey 100% of the authorized and outstanding member interests in DEVCO to the Partnership or its designee. As of March 31, 2019, neither Ergon nor the Partnership has exercised their options under the Agreement. In December 2018, the Partnership and Ergon were informed that Kingfisher Midstream made the decision to suspend future investments in Cimarron Express as Kingfisher Midstream determined that the anticipated volumes from the currently dedicated acreage, and the resultant project economics, did not support additional investment from Kingfisher Midstream. As of December 31, 2018, Cimarron Express had spent approximately $30.6 million on the pipeline project, primarily related to the purchase of steel pipe and equipment, rights of way and engineering and design services. Cimarron Express recorded a $20.9 million impairment charge in the fourth quarter of 2018 to reduce the carrying amount of its assets to their estimated fair value. In addition to its capital contributions to Cimarron Express, Ergon’s interest in DEVCO includes internal Ergon labor and capitalized interest that bring its investment in DEVCO to approximately $17.8 million through March 31, 2019. Ergon recorded a $10.0 million other-than-temporary impairment on its investment in Cimarron Express as of December 31, 2018 to reduce its investment to its estimated fair value. As a result, the Partnership considered the SEC staff’s opinions outlined in SAB 107 Topic 5.T Accounting for Expenses or Liabilities Paid by Principal Stockholders. The Agreement was designed to have the Partnership, ultimately and from the onset, bear any risk of loss on the construction of the pipeline project and eventually own a 50% interest in the pipeline. As a result, the Partnership recorded on a push down basis a $10.0 million impairment of Ergon’s investment in Cimarron Express in its consolidated results of operations during the year ended December 31, 2018, and a contingent liability payable to Ergon as of December 31, 2018. In April 2019, assets from the project were sold to a third-party for approximately $1.4 million over the fair market value that was estimated at December 31, 2018. As a result, the Partnership will record in April 2019, on a push down basis, a gain on the sale based on Ergon’s 50% interest in the assets.

LONG-TERM INCENTIVE PLAN

LONG-TERM INCENTIVE PLAN	3 Months Ended
LONG-TERM INCENTIVE PLAN	Mar. 31, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
LONG-TERM INCENTIVE PLAN	LONG-TERM INCENTIVE PLAN In July 2007, the general partner adopted the Long-Term Incentive Plan (the “LTIP”), which is administered by the compensation committee of the Board. Effective April 29, 2014, the Partnership’s unitholders approved an amendment to the LTIP to increase the number of common units reserved for issuance under the incentive plan to 4,100,000 common units, subject to adjustments for certain events. Although other types of awards are contemplated under the LTIP, currently outstanding awards include “phantom” units, which convey the right to receive common units upon vesting, and “restricted” units, which are grants of common units restricted until the time of vesting. The phantom unit awards also include distribution equivalent rights (“DERs”). Subject to applicable earning criteria, a DER entitles the grantee to a cash payment equal to the cash distribution paid on an outstanding common unit prior to the vesting date of the underlying award. Recipients of restricted and phantom units are entitled to receive cash distributions paid on common units during the vesting period which are reflected initially as a reduction of partners’ capital. Distributions paid on units which ultimately do not vest are reclassified as compensation expense. Awards granted to date are equity awards and, accordingly, the fair value of the awards as of the grant date is expensed over the vesting period. In connection with each anniversary of joining the Board, restricted common units are granted to the independent directors. The units vest in one-third increments over three years. The following table includes information on outstanding grants made to the directors under the LTIP: Grant Date Number of Units Weighted Average Grant Date Fair Value (1) Grant Date Total Fair Value (in thousands) December 2016 10,950 $ 6.85 $ 75 December 2017 15,306 $ 4.85 $ 74 December 2018 23,436 $ 1.20 $ 28 _________________ (1) Fair value is the closing market price on the grant date of the awards. In addition, the independent directors received common unit grants that have no vesting requirement as part of their compensation. The following table includes information on grants made to the directors under the LTIP that have no vesting requirement: Grant Date Number of Units Weighted Average Grant Date Fair Value (1) Grant Date Total Fair Value (in thousands) December 2016 10,220 $ 6.85 $ 70 December 2017 14,286 $ 4.85 $ 69 December 2018 21,875 $ 1.20 $ 26 _________________ (1) Fair value is the closing market price on the grant date of the awards. The Partnership also grants phantom units to employees. These grants are equity awards under ASC 718 – Stock Compensation and, accordingly, the fair value of the awards as of the grant date is expensed over the vesting period. The following table includes information on the outstanding grants: Grant Date Number of Units Weighted Average Grant Date Fair Value (1) Grant Date Total Fair Value (in thousands) March 2017 323,339 $ 7.15 $ 2,312 March 2018 457,984 $ 4.77 $ 2,185 March 2019 524,997 $ 1.14 $ 598 _________________ (1) Fair value is the closing market price on the grant date of the awards. The unrecognized estimated compensation cost of outstanding phantom and restricted units at March 31, 2019 , was $1.7 million , which will be expensed over the remaining vesting period. The Partnership’s equity-based incentive compensation expense for the three months ended March 31, 2018 and 2019 , was $0.5 million and $0.3 million , respectively. Activity pertaining to phantom and restricted common unit awards granted under the LTIP is as follows: Number of Units Weighted Average Grant Date Fair Value Nonvested at December 31, 2018 998,219 $ 5.88 Granted 524,997 1.14 Vested 366,282 4.80 Forfeited — — Nonvested at March 31, 2019 1,156,934 $ 3.60

EMPLOYEE BENEFIT PLAN

EMPLOYEE BENEFIT PLAN	3 Months Ended
EMPLOYEE BENEFIT PLAN	Mar. 31, 2019
Retirement Benefits [Abstract]
EMPLOYEE BENEFIT PLAN	EMPLOYEE BENEFIT PLANS Under the Partnership’s 401(k) Plan, which was instituted in 2009 , employees who meet specified service requirements may contribute a percentage of their total compensation, up to a specified maximum, to the 401(k) Plan. The Partnership may match each employee’s contribution, up to a specified maximum, in full or on a partial basis. The Partnership recognized expense of $0.3 million for each of the three months ended March 31, 2018 and 2019 , for discretionary contributions under the 401(k) Plan. The Partnership may also make annual lump-sum contributions to the 401(k) Plan irrespective of the employee’s contribution match. The Partnership may make a discretionary annual contribution in the form of profit sharing calculated as a percentage of an employee’s eligible compensation. This contribution is retirement income under the qualified 401(k) Plan. Annual profit sharing contributions to the 401(k) Plan are submitted to and approved by the Board. The Partnership recognized expense of $0.1 million and $0.2 million for the three months ended March 31, 2018 and 2019 , respectively, for discretionary profit sharing contributions under the 401(k) Plan. Under the Partnership’s Employee Unit Purchase Plan (the “Unit Purchase Plan”), which was instituted in January 2015, employees have the opportunity to acquire or increase their ownership of common units representing limited partner interests in the Partnership. Eligible employees who enroll in the Unit Purchase Plan may elect to have a designated whole percentage, up to a specified maximum, of their eligible compensation for each pay period withheld for the purchase of common units at a discount to the then current market value. A maximum of 1,000,000 common units may be delivered under the Unit Purchase Plan, subject to adjustment for a recapitalization, split, reorganization, or similar event pursuant to the terms of the Unit Purchase Plan. The Partnership recognized compensation expense of less than $0.1 million for the each of the three months ended March 31, 2018 and 2019 , in connection with the Unit Purchase Plan.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	3 Months Ended
FAIR VALUE MEASUREMENTS	Mar. 31, 2019
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS The Partnership uses valuation techniques, such as the market approach (comparable market prices), the income approach (present value of future income or cash flow), and the cost approach (cost to replace the service capacity of an asset or replacement cost) to value assets and liabilities required to be measured at fair value, as appropriate. The Partnership uses an exit price when determining the fair value. The exit price represents amounts that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. The Partnership utilizes a three-tier fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value into three broad levels. The following is a brief description of those three levels: Level 1 Observable inputs such as quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2 Inputs other than quoted prices that are observable for these assets or liabilities, either directly or indirectly. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. Level 3 Unobservable inputs in which there is little market data, which requires the reporting entity to develop its own assumptions. This hierarchy requires the use of observable market data, when available, to minimize the use of unobservable inputs when determining fair value. In periods in which they occur, the Partnership recognizes transfers into and out of Level 3 as of the end of the reporting period. There were no transfers during the three months ended March 31, 2019 . Transfers out of Level 3 represent existing assets and liabilities that were classified previously as Level 3 for which the observable inputs became a more significant portion of the fair value estimates. Determining the appropriate classification of the Partnership’s fair value measurements within the fair value hierarchy requires management’s judgment regarding the degree to which market data is observable or corroborated by observable market data. The Partnership’s recurring financial assets and liabilities subject to fair value measurements and the necessary disclosures are as follows (in thousands): Fair Value Measurements as of December 31, 2018 Description Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Interest rate swap assets $ 44 $ — $ 44 $ — Total swap assets $ 44 $ — $ 44 $ — As of March 31, 2019 , the Partnership had no interest rate swap agreements. Fair Value of Other Financial Instruments The following disclosure of the estimated fair value of financial instruments is made in accordance with accounting guidance for financial instruments. The Partnership has determined the estimated fair values by using available market information and valuation methodologies. Considerable judgment is required in interpreting market data to develop the estimates of fair value. The use of different market assumptions or valuation methodologies may have a material effect on the estimated fair value amounts. At March 31, 2019 , the carrying values on the unaudited condensed consolidated balance sheets for cash and cash equivalents (classified as Level 1), accounts receivable, and accounts payable approximate their fair value because of their short-term nature. Based on the borrowing rates currently available to the Partnership for credit agreement debt with similar terms and maturities and consideration of the Partnership’s non-performance risk, long-term debt associated with the Partnership’s credit agreement at March 31, 2019 , approximates its fair value. The fair value of the Partnership’s long-term debt was calculated using observable inputs (LIBOR for the risk-free component) and unobservable company-specific credit spread information. As such, the Partnership considers this debt to be Level 3.

LEASES (Notes)

LEASES (Notes)	3 Months Ended
LEASES (Notes)	Mar. 31, 2019
Leases [Abstract]
Lessee, Leases [Policy Text Block]	LEASES The Partnership adopted ASU 2016-02, Leases (Topic 842) as of January 1, 2019, using the modified retrospective approach applied at the beginning of the period of adoption. The Partnership elected the package of practical expedients permitted under the transition guidance within the new standard, which, among other things, allowed it to carry forward the historical lease classification. Adoption of the new standard resulted in the recording of additional net right of use operating lease assets and operating lease liabilities of approximately $11.8 million and $11.9 million , respectively, as of January 1, 2019. The standard did not materially impact the consolidated statement of operations and had no impact on cash flows. The Partnership leases certain office space, land and equipment. Leases with an initial term of 12 months or less are not recorded on the balance sheet; lease expense for these leases is recognized as paid over the lease term. For real property leases, the Partnership has elected the practical expedient to not separate nonlease components (e.g., common-area maintenance costs) from lease components and to instead account for each component as a single lease component. For leases that do not contain an implicit interest rate, the Partnership uses its most recent incremental borrowing rate. Some real property and equipment leases contain options to renew, with renewal terms that can extend indefinitely. The exercise of such lease renewal options is at the Partnership’s sole discretion. Certain equipment leases also contain purchase options and residual value guarantees. The Partnership determines the lease term at the lease commencement date as the non-cancellable period of the lease, including options to extend or terminate the lease when such an option is reasonably certain to be exercised. The Partnership uses various data to analyze these options, including historical trends, current expectations and useful lives of assets related to the lease. As of Classification March 31, 2019 (thousands) Assets Operating lease assets Operating lease assets $ 11,594 Finance lease assets Other noncurrent assets 631 Total leased assets $ 12,225 Liabilities Current Operating lease liabilities Current operating lease liability $ 2,768 Finance lease liabilities Other current liabilities 263 Noncurrent Operating lease liabilities Noncurrent operating lease liability 8,935 Finance lease liabilities Other long-term liabilities 368 Total lease liabilities $ 12,334 Future commitments, including options to extend lease terms that are reasonably certain of being exercised, related to leases at March 31, 2019, are summarized below (in thousands): Operating Leases Financing Leases Twelve months ending March 31, 2020 $ 2,993 $ 285 Twelve months ending March 31, 2021 2,447 215 Twelve months ending March 31, 2022 1,843 129 Twelve months ending March 31, 2023 1,413 42 Twelve months ending March 31, 2024 1,199 — Thereafter 5,208 — Total 15,103 671 Less: Interest 3,400 40 Present value of lease liabilities $ 11,703 $ 631 Future non-cancellable commitments related to operating leases at December 31, 2018, are summarized below (in thousands): Operating Leases Year ending December 31, 2019 $ 2,862 Year ending December 31, 2020 1,904 Year ending December 31, 2021 1,242 Year ending December 31, 2022 640 Year ending December 31, 2023 548 Thereafter 1,259 Total future minimum lease payments $ 8,455 The following table summarizes the Partnership’s total lease cost by type as well as cash flow information (in thousands): Three Months ended Classification 2019 Total Lease Cost by Type: Operating lease cost (1) Operating Expenses $ 1,142 Finance lease cost Amortization of leased assets Operating Expenses 70 Interest on lease liabilities Interest Expense 7 Net lease cost $ 1,219 Supplemental cash flow disclosures: Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ (750 ) Operating cash flows from finance leases $ (12 ) Financing cash flows from finance leases $ (66 ) Leased assets obtained in exchange for new operating lease liabilities $ 569 Leased assets obtained in exchange for new finance lease liabilities $ 112 ____________________ (1) Includes short-term leases and variable lease costs, which are immaterial. As of March 31, 2019 Lease Term and Discount Rate Weighted-average remaining lease term (years) Operating leases 9.0 Finance leases 2.8 Weighted-average discount rate Operating leases 5.65 % Finance leases 4.20 % The Partnership also incurs costs associated with acquiring and maintaining rights-of-way. The contracts for these generally either extend beyond one year but can be cancelled at any time should they no longer be required for operations or have no contracted term but contain perpetual annual or monthly renewal options. Rights-of-way generally do not provide for exclusive use of the land and as such are not accounted for as leases.

OPERATING SEGMENTS

OPERATING SEGMENTS	3 Months Ended
OPERATING SEGMENTS	Mar. 31, 2019
Segment Reporting [Abstract]
OPERATING SEGMENTS	OPERATING SEGMENTS The Partnership’s operations consist of four reportable segments: (i) asphalt terminalling services, (ii) crude oil terminalling services, (iii) crude oil pipeline services and (iv) crude oil trucking services. ASPHALT TERMINALLING SERVICES —The Partnership provides asphalt product and residual fuel terminalling services, including storage, blending, processing and throughput services. On July 12, 2018, the Partnership sold three asphalt facilities. See Note 6 for additional information. The Partnership has 53 terminalling facilities located in 26 states. CRUDE OIL TERMINALLING SERVICES —The Partnership provides crude oil terminalling services at its terminalling facility located in Oklahoma. CRUDE OIL PIPELINE SERVICES —The Partnership owns and operates pipeline systems that gather crude oil purchased by its customers and transports it to refiners, to common carrier pipelines for ultimate delivery to refiners or to terminalling facilities owned by the Partnership and others. The Partnership refers to its pipeline system located in Oklahoma and the Texas Panhandle as the Mid-Continent pipeline system. Crude oil product sales revenues consist of sales proceeds recognized for the sale of crude oil to third-party customers. CRUDE OIL TRUCKING SERVICES — The Partnership uses its owned and leased tanker trucks to gather crude oil for its customers at remote wellhead locations generally not covered by pipeline and gathering systems and to transport the crude oil to aggregation points and storage facilities located along pipeline gathering and transportation systems. The Partnership’s management evaluates segment performance based upon operating margin, excluding amortization and depreciation, which includes revenues from related parties and external customers and operating expense, excluding depreciation and amortization. Operating margin, excluding depreciation and amortization (in the aggregate and by segment) is presented in the following table. The Partnership computes the components of operating margin, excluding depreciation and amortization by using amounts that are determined in accordance with GAAP. The Partnership accounts for intersegment product sales as if the sales were to third parties, that is, at current market prices. A reconciliation of operating margin, excluding depreciation and amortization to income before income taxes, which is its nearest comparable GAAP financial measure, is included in the following table. The Partnership believes that investors benefit from having access to the same financial measures being utilized by management. Operating margin, excluding depreciation and amortization is an important measure of the economic performance of the Partnership’s core operations. This measure forms the basis of the Partnership’s internal financial reporting and is used by its management in deciding how to allocate capital resources among segments. Income before income taxes, alternatively, includes expense items, such as depreciation and amortization, general and administrative expenses and interest expense, which management does not consider when evaluating the core profitability of the Partnership’s operations. The following table reflects certain financial data for each segment for the periods indicated (in thousands): Three Months ended 2018 2019 Asphalt Terminalling Services Service revenue: Third-party revenue $ 5,132 $ 6,982 Related-party revenue 6,321 4,118 Lease revenue: Third-party revenue 9,458 9,763 Related-party revenue 7,702 4,940 Total revenue for reportable segment 28,613 25,803 Operating expense, excluding depreciation and amortization 13,333 12,285 Operating margin, excluding depreciation and amortization $ 15,280 $ 13,518 Total assets (end of period) $ 170,473 $ 147,844 Crude Oil Terminalling Services Service revenue: Third-party revenue $ 4,585 $ 3,573 Intersegment revenue — 298 Lease revenue: Third-party revenue 15 — Total revenue for reportable segment 4,600 3,871 Operating expense, excluding depreciation and amortization 1,275 1,282 Operating margin, excluding depreciation and amortization $ 3,325 $ 2,589 Total assets (end of period) $ 68,160 $ 67,934 Three Months ended 2018 2019 Crude Oil Pipeline Services Service revenue: Third-party revenue $ 2,061 $ 2,498 Related-party revenue — 101 Lease revenue: Third-party revenue 235 — Product sales revenue: Third-party revenue 3,508 58,924 Total revenue for reportable segment 5,804 61,523 Operating expense, excluding depreciation and amortization 2,785 2,722 Intersegment operating expense 442 1,627 Third-party cost of product sales 2,637 24,587 Related-party cost of product sales — 30,774 Operating margin, excluding depreciation and amortization $ (60 ) $ 1,813 Total assets (end of period) $ 116,845 $ 98,722 Crude Oil Trucking Services Service revenue Third-party revenue $ 5,540 $ 2,833 Intersegment revenue 442 1,329 Lease revenue: Third-party revenue 97 — Product sales revenue: Third-party revenue 6 — Total revenue for reportable segment 6,085 4,162 Operating expense, excluding depreciation and amortization 6,375 4,220 Operating margin, excluding depreciation and amortization $ (290 ) $ (58 ) Total assets (end of period) $ 6,113 $ 5,156 Total operating margin, excluding depreciation and amortization (1) $ 18,255 $ 17,862 Total Segment Revenues $ 45,102 $ 95,359 Elimination of Intersegment Revenues (442 ) (1,627 ) Consolidated Revenues $ 44,660 $ 93,732 ____________________ (1) The following table reconciles segment operating margin (excluding depreciation and amortization) to income before income taxes (in thousands): Three Months ended 2018 2019 Operating margin, excluding depreciation and amortization $ 18,255 $ 17,862 Depreciation and amortization (7,367 ) (6,734 ) General and administrative expense (4,221 ) (3,693 ) Asset impairment expense (616 ) (1,119 ) Gain (loss) on sale of assets (236 ) 1,724 Interest expense (3,569 ) (4,271 ) Gain on sale of unconsolidated affiliate 2,225 — Income before income taxes $ 4,471 $ 3,769

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
COMMITMENTS AND CONTINGENCIES	Mar. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
COMMITMENT AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES The Partnership is from time to time subject to various legal actions and claims incidental to its business. Management believes that these legal proceedings will not have a material adverse effect on the financial position, results of operations or cash flows of the Partnership. Once management determines that information pertaining to a legal proceeding indicates that it is probable that a liability has been incurred and the amount of such liability can be reasonably estimated, an accrual is established equal to its estimate of the likely exposure. The Partnership has contractual obligations to perform dismantlement and removal activities in the event that some of its asphalt product and residual fuel oil terminalling and storage assets are abandoned. These obligations include varying levels of activity including completely removing the assets and returning the land to its original state. The Partnership has determined that the settlement dates related to the retirement obligations are indeterminate. The assets with indeterminate settlement dates have been in existence for many years and with regular maintenance will continue to be in service for many years to come. Also, it is not possible to predict when demands for the Partnership’s terminalling and storage services will cease, and the Partnership does not believe that such demand will cease for the foreseeable future. Accordingly, the Partnership believes the date when these assets will be abandoned is indeterminate. With no reasonably determinable abandonment date, the Partnership cannot reasonably estimate the fair value of the associated asset retirement obligations. Management believes that if the Partnership’s asset retirement obligations were settled in the foreseeable future the present value of potential cash flows that would be required to settle the obligations based on current costs are not material. The Partnership will record asset retirement obligations for these assets in the period in which sufficient information becomes available for it to reasonably determine the settlement dates.

INCOME TAXES

INCOME TAXES	3 Months Ended
INCOME TAXES	Mar. 31, 2019
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES In relation to the Partnership’s taxable subsidiary, the tax effects of temporary differences between the tax basis of assets and liabilities and their financial reporting amounts at March 31, 2019 , are presented below (dollars in thousands): Deferred Tax Asset Difference in bases of property, plant and equipment $ 260 Net operating loss carryforwards 7 Deferred tax asset 267 Less: valuation allowance 267 Net deferred tax asset $ — The Partnership has considered the taxable income projections in future years, whether future revenue and operating cost projections will produce enough taxable income to realize the deferred tax asset based on existing service rates and cost structures and the Partnership’s earnings history exclusive of the loss that created the future deductible amount for the Partnership’s subsidiary that is taxed as a corporation for purposes of determining the likelihood of realizing the benefits of the deferred tax assets. As a result of the Partnership’s consideration of these factors, the Partnership has provided a valuation allowance against its deferred tax asset as of March 31, 2019 .

RECENTLY ISSUED ACCOUNTING STAN

RECENTLY ISSUED ACCOUNTING STANDARDS	3 Months Ended
RECENTLY ISSUED ACCOUNTING STANDARDS	Mar. 31, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
RECENTLY ISSUED ACCOUNTING STANDARDS	RECENTLY ISSUED ACCOUNTING STANDARDS Except as discussed below and in the 2018 Form 10-K, there have been no new accounting pronouncements that have become effective or have been issued during the three months ended March 31, 2019 , that are of significance or potential significance to the Partnership. In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842)”. This is a comprehensive update to the lease accounting topic in the Codification intended to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. The amendments in ASU 2016-02 include a revised definition of a lease as well as certain scope exceptions. The changes primarily impact lessee accounting, while lessor accounting is largely unchanged from previous GAAP. The Partnership adopted this standard as of January 1, 2019, using the modified retrospective approach. See Note 3 and Note 14 for disclosures related to the adoption of this standard and the impact on the Partnership’s financial position, results of operations and cash flows.

REVENUE Minimum Future Annual L

REVENUE Minimum Future Annual Lease Rentals Due (Tables)	3 Months Ended
REVENUE Minimum Future Annual Lease Rentals Due (Tables)	Mar. 31, 2019
Lessor Disclosure [Abstract]
Lessor, Operating Lease, Payments to be Received, Maturity [Table Text Block]	Revenue Related to Minimum Future Annual Lease Rentals Due by Period Twelve months ending March 31, 2020 $ 55,176 Twelve months ending March 31, 2021 52,360 Twelve months ending March 31, 2022 46,637 Twelve months ending March 31, 2023 36,655 Twelve months ending March 31, 2024 24,798 Thereafter 19,220 Total revenue related to minimum future annual lease rentals $ 234,846

REVENUE Revenue from Contracts

REVENUE Revenue from Contracts with Customers (Tables)	3 Months Ended
REVENUE Revenue from Contracts with Customers (Tables)	Mar. 31, 2019
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]	As of March 31, 2019 , the Partnership has service revenue performance obligations satisfied over time under asphalt storage, throughput and handling contracts that are wholly or partially unsatisfied. The service revenue related to these performance obligations will be recognized as follows (in thousands): Revenue Related to Future Performance Obligations Due by Period (1) Twelve months ending March 31, 2020 $ 30,705 Twelve months ending March 31, 2021 29,704 Twelve months ending March 31, 2022 25,487 Twelve months ending March 31, 2023 18,903 Twelve months ending March 31, 2024 11,711 Thereafter 7,841 Total revenue related to future performance obligations $ 124,351 ____________________ (1) Excluded from the table is revenue that is either constrained or related to performance obligations that are wholly unsatisfied as of March 31, 2019 .
Disaggregation of Revenue [Table Text Block]	Disaggregation of revenue from contracts with customers for each operating segment by revenue type is presented as follows (in thousands): Three Months ended March 31, 2018 Asphalt Terminalling Services Crude Oil Terminalling Services Crude Oil Pipeline Services Crude Oil Trucking Services Total Third-party revenue: Fixed storage, throughput and other revenue $ 3,549 $ 4,081 $ — $ — $ 7,630 Variable throughput revenue 117 504 — — 621 Variable reimbursement revenue 1,466 — — — 1,466 Crude oil transportation revenue — — 2,061 5,540 7,601 Crude oil product sales revenue — — 3,508 6 3,514 Related-party revenue: Fixed storage, throughput and other revenue 4,631 — — — 4,631 Variable reimbursement revenue 1,690 — — — 1,690 Total revenue from contracts with customers $ 11,453 $ 4,585 $ 5,569 $ 5,546 $ 27,153 Three Months ended March 31, 2019 Asphalt Terminalling Services Crude Oil Terminalling Services Crude Oil Pipeline Services Crude Oil Trucking Services Total Third-party revenue: Fixed storage, throughput and other revenue $ 4,983 $ 3,069 $ — $ — $ 8,052 Variable throughput revenue 3 504 — — 507 Variable reimbursement revenue 1,996 — — — 1,996 Crude oil transportation revenue — — 2,498 2,833 5,331 Crude oil product sales revenue — — 58,924 — 58,924 Related-party revenue: Fixed storage, throughput and other revenue 2,848 — 83 — 2,931 Variable reimbursement revenue 1,270 — 18 — 1,288 Total revenue from contracts with customers $ 11,100 $ 3,573 $ 61,523 $ 2,833 $ 79,029

RESTRUCTURING CHARGES (Tables)

RESTRUCTURING CHARGES (Tables)	3 Months Ended
RESTRUCTURING CHARGES (Tables)	Mar. 31, 2019
Crude Oil Trucking Services [Member] \| West Texas Trucking Market Exit Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Costs [Table Text Block]	Changes in the accrued amounts pertaining to the restructuring charges are summarized as follows (in thousands): Three Months ended 2018 Beginning balance $ 286 Cash payments 49 Ending balance $ 237

EQUITY METHOD INVESTMENT (Table

EQUITY METHOD INVESTMENT (Tables)	3 Months Ended
EQUITY METHOD INVESTMENT (Tables)	Mar. 31, 2019
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments [Table Text Block]

PROPERTY, PLANT AND EQUIPMENT (

PROPERTY, PLANT AND EQUIPMENT (Tables)	3 Months Ended
PROPERTY, PLANT AND EQUIPMENT (Tables)	Mar. 31, 2019
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	Estimated Useful Lives (Years) December 31, 2018 March 31, (dollars in thousands) Land N/A $ 24,705 $ 24,705 Land improvements 10-20 5,758 5,798 Pipelines and facilities 5-30 116,155 117,188 Storage and terminal facilities 10-35 321,096 322,476 Transportation equipment 3-10 2,798 1,782 Office property and equipment and other 3-20 26,980 27,186 Pipeline linefill and tank bottoms N/A 10,297 8,882 Construction-in-progress N/A 4,026 3,622 Property, plant and equipment, gross 511,815 511,639 Accumulated depreciation (263,554 ) (268,576 ) Property, plant and equipment, net $ 248,261 $ 243,063

DEBT Fair Values of Derivative

DEBT Fair Values of Derivative Instruments (Tables)	3 Months Ended
DEBT Fair Values of Derivative Instruments (Tables)	Mar. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Other Derivatives Not Designated as Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block]	The following provides information regarding the Partnership’s assets and liabilities related to its interest rate swap agreements as of the periods indicated (in thousands): Derivatives Not Designated as Hedging Instruments Balance Sheet Location Fair Value of Derivatives December 31, 2018 Interest rate swap assets - current Other current assets $ 44 Changes in the fair value of the interest rate swaps are reflected in the unaudited condensed consolidated statements of operations as follows (in thousands): Derivatives Not Designated as Hedging Instruments Location of Gain (Loss) Recognized in Net Income on Derivatives Amount of Gain (Loss) Recognized in Net Income on Derivatives Three Months ended 2018 2019 Interest rate swaps Interest expense, net of capitalized interest $ 354 $ (44 )

NET INCOME PER LIMITED PARTNE_2

NET INCOME PER LIMITED PARTNER UNIT (Tables)	3 Months Ended
NET INCOME PER LIMITED PARTNER UNIT (Tables)	Mar. 31, 2019
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Net Income (Loss) Per Common and Subordinated Units	The following sets forth the computation of basic and diluted net income per common unit (in thousands, except per unit data): Three Months ended 2018 2019 Net income $ 4,442 $ 3,757 General partner interest in net income 231 105 Preferred interest in net income 6,278 6,279 Net loss available to limited partners $ (2,067 ) $ (2,627 ) Basic and diluted weighted average number of units: Common units 40,289 40,678 Restricted and phantom units 833 769 Total units 41,122 41,447 Basic and diluted net loss per common unit $ (0.05 ) $ (0.06 )

LONG-TERM INCENTIVE PLAN (Table

LONG-TERM INCENTIVE PLAN (Tables)	3 Months Ended
LONG-TERM INCENTIVE PLAN (Tables)	Mar. 31, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-based Compensation Arrangements by Share-based Payment Award, Restricted Stock Units, Vested and Expected to Vest [Table Text Block]	In connection with each anniversary of joining the Board, restricted common units are granted to the independent directors. The units vest in one-third increments over three years. The following table includes information on outstanding grants made to the directors under the LTIP: Grant Date Number of Units Weighted Average Grant Date Fair Value (1) Grant Date Total Fair Value (in thousands) December 2016 10,950 $ 6.85 $ 75 December 2017 15,306 $ 4.85 $ 74 December 2018 23,436 $ 1.20 $ 28 _________________ (1) Fair value is the closing market price on the grant date of the awards. In addition, the independent directors received common unit grants that have no vesting requirement as part of their compensation. The following table includes information on grants made to the directors under the LTIP that have no vesting requirement: Grant Date Number of Units Weighted Average Grant Date Fair Value (1) Grant Date Total Fair Value (in thousands) December 2016 10,220 $ 6.85 $ 70 December 2017 14,286 $ 4.85 $ 69 December 2018 21,875 $ 1.20 $ 26 _________________ (1) Fair value is the closing market price on the grant date of the awards.
Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block]	The Partnership also grants phantom units to employees. These grants are equity awards under ASC 718 – Stock Compensation and, accordingly, the fair value of the awards as of the grant date is expensed over the vesting period. The following table includes information on the outstanding grants: Grant Date Number of Units Weighted Average Grant Date Fair Value (1) Grant Date Total Fair Value (in thousands) March 2017 323,339 $ 7.15 $ 2,312 March 2018 457,984 $ 4.77 $ 2,185 March 2019 524,997 $ 1.14 $ 598 _________________ (1) Fair value is the closing market price on the grant date of the awards.
Schedule Of Phantom Common Units And Restricted Common Units Activity	Activity pertaining to phantom and restricted common unit awards granted under the LTIP is as follows: Number of Units Weighted Average Grant Date Fair Value Nonvested at December 31, 2018 998,219 $ 5.88 Granted 524,997 1.14 Vested 366,282 4.80 Forfeited — — Nonvested at March 31, 2019 1,156,934 $ 3.60

FAIR VALUE MEASUREMENTS Fair Va

FAIR VALUE MEASUREMENTS Fair Value Measurements (Tables)	3 Months Ended
FAIR VALUE MEASUREMENTS Fair Value Measurements (Tables)	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value, by Balance Sheet Grouping [Table Text Block]	The Partnership’s recurring financial assets and liabilities subject to fair value measurements and the necessary disclosures are as follows (in thousands): Fair Value Measurements as of December 31, 2018 Description Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Interest rate swap assets $ 44 $ — $ 44 $ — Total swap assets $ 44 $ — $ 44 $ —

LEASES (Tables)

LEASES (Tables)	3 Months Ended
LEASES (Tables)	Mar. 31, 2019
Leases [Abstract]
supplemental balance sheet information related to leases [Table Text Block]	As of Classification March 31, 2019 (thousands) Assets Operating lease assets Operating lease assets $ 11,594 Finance lease assets Other noncurrent assets 631 Total leased assets $ 12,225 Liabilities Current Operating lease liabilities Current operating lease liability $ 2,768 Finance lease liabilities Other current liabilities 263 Noncurrent Operating lease liabilities Noncurrent operating lease liability 8,935 Finance lease liabilities Other long-term liabilities 368 Total lease liabilities $ 12,334
Lease Liability, Maturity [Table Text Block]	Future commitments, including options to extend lease terms that are reasonably certain of being exercised, related to leases at March 31, 2019, are summarized below (in thousands): Operating Leases Financing Leases Twelve months ending March 31, 2020 $ 2,993 $ 285 Twelve months ending March 31, 2021 2,447 215 Twelve months ending March 31, 2022 1,843 129 Twelve months ending March 31, 2023 1,413 42 Twelve months ending March 31, 2024 1,199 — Thereafter 5,208 — Total 15,103 671 Less: Interest 3,400 40 Present value of lease liabilities $ 11,703 $ 631 Future non-cancellable commitments related to operating leases at December 31, 2018, are summarized below (in thousands): Operating Leases Year ending December 31, 2019 $ 2,862 Year ending December 31, 2020 1,904 Year ending December 31, 2021 1,242 Year ending December 31, 2022 640 Year ending December 31, 2023 548 Thereafter 1,259 Total future minimum lease payments $ 8,455
Lease, Cost [Table Text Block]	The following table summarizes the Partnership’s total lease cost by type as well as cash flow information (in thousands): Three Months ended Classification 2019 Total Lease Cost by Type: Operating lease cost (1) Operating Expenses $ 1,142 Finance lease cost Amortization of leased assets Operating Expenses 70 Interest on lease liabilities Interest Expense 7 Net lease cost $ 1,219 Supplemental cash flow disclosures: Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ (750 ) Operating cash flows from finance leases $ (12 ) Financing cash flows from finance leases $ (66 ) Leased assets obtained in exchange for new operating lease liabilities $ 569 Leased assets obtained in exchange for new finance lease liabilities $ 112 ____________________ (1) Includes short-term leases and variable lease costs, which are immaterial. As of March 31, 2019 Lease Term and Discount Rate Weighted-average remaining lease term (years) Operating leases 9.0 Finance leases 2.8 Weighted-average discount rate Operating leases 5.65 % Finance leases 4.20 %

OPERATING SEGMENTS (Tables)

OPERATING SEGMENTS (Tables)	3 Months Ended
OPERATING SEGMENTS (Tables)	Mar. 31, 2019
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	Three Months ended 2018 2019 Asphalt Terminalling Services Service revenue: Third-party revenue $ 5,132 $ 6,982 Related-party revenue 6,321 4,118 Lease revenue: Third-party revenue 9,458 9,763 Related-party revenue 7,702 4,940 Total revenue for reportable segment 28,613 25,803 Operating expense, excluding depreciation and amortization 13,333 12,285 Operating margin, excluding depreciation and amortization $ 15,280 $ 13,518 Total assets (end of period) $ 170,473 $ 147,844 Crude Oil Terminalling Services Service revenue: Third-party revenue $ 4,585 $ 3,573 Intersegment revenue — 298 Lease revenue: Third-party revenue 15 — Total revenue for reportable segment 4,600 3,871 Operating expense, excluding depreciation and amortization 1,275 1,282 Operating margin, excluding depreciation and amortization $ 3,325 $ 2,589 Total assets (end of period) $ 68,160 $ 67,934 Three Months ended 2018 2019 Crude Oil Pipeline Services Service revenue: Third-party revenue $ 2,061 $ 2,498 Related-party revenue — 101 Lease revenue: Third-party revenue 235 — Product sales revenue: Third-party revenue 3,508 58,924 Total revenue for reportable segment 5,804 61,523 Operating expense, excluding depreciation and amortization 2,785 2,722 Intersegment operating expense 442 1,627 Third-party cost of product sales 2,637 24,587 Related-party cost of product sales — 30,774 Operating margin, excluding depreciation and amortization $ (60 ) $ 1,813 Total assets (end of period) $ 116,845 $ 98,722 Crude Oil Trucking Services Service revenue Third-party revenue $ 5,540 $ 2,833 Intersegment revenue 442 1,329 Lease revenue: Third-party revenue 97 — Product sales revenue: Third-party revenue 6 — Total revenue for reportable segment 6,085 4,162 Operating expense, excluding depreciation and amortization 6,375 4,220 Operating margin, excluding depreciation and amortization $ (290 ) $ (58 ) Total assets (end of period) $ 6,113 $ 5,156 Total operating margin, excluding depreciation and amortization (1) $ 18,255 $ 17,862 Total Segment Revenues $ 45,102 $ 95,359 Elimination of Intersegment Revenues (442 ) (1,627 ) Consolidated Revenues $ 44,660 $ 93,732 ____________________ (1) The following table reconciles segment operating margin (excluding depreciation and amortization) to income before income taxes (in thousands): Three Months ended 2018 2019 Operating margin, excluding depreciation and amortization $ 18,255 $ 17,862 Depreciation and amortization (7,367 ) (6,734 ) General and administrative expense (4,221 ) (3,693 ) Asset impairment expense (616 ) (1,119 ) Gain (loss) on sale of assets (236 ) 1,724 Interest expense (3,569 ) (4,271 ) Gain on sale of unconsolidated affiliate 2,225 — Income before income taxes $ 4,471 $ 3,769

INCOME TAXES (Tables)

INCOME TAXES (Tables)	3 Months Ended
INCOME TAXES (Tables)	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Schedule of Deferred Tax Assets	In relation to the Partnership’s taxable subsidiary, the tax effects of temporary differences between the tax basis of assets and liabilities and their financial reporting amounts at March 31, 2019 , are presented below (dollars in thousands): Deferred Tax Asset Difference in bases of property, plant and equipment $ 260 Net operating loss carryforwards 7 Deferred tax asset 267 Less: valuation allowance 267 Net deferred tax asset $ —

ORGANIZATION AND NATURE OF BU_2

ORGANIZATION AND NATURE OF BUSINESS (Narrative) (Details)	3 Months Ended
ORGANIZATION AND NATURE OF BUSINESS (Narrative) (Details)	Mar. 31, 2019Operating-segmentsStates
ORGANIZATION AND NATURE OF BUSINESS [Abstract]
Number of states in which entity operates (in states) \| States	27
Number of operating segments (in operating segments) \| Operating-segments	4

REVENUE Narrative (Details)

REVENUE Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
REVENUE Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Third-party revenue	$ 15,886	$ 17,318
Accounts Receivable, Net, Current	28,561		$ 35,683
Revenue related to future performance obligations	124,351
Billed contract accounts receivable	25,800		34,600
Contract with Customer, Liability, Noncurrent	10,100		$ 5,900
Changes in deferred revenue [Roll Forward]
Deferred revenue, additions	7,300
Contract with customer, liability, revenue recognized	3,100
Fixed Storage and Throughput Revenue [Member]
Third-party revenue	8,052	7,630
Variable Throughput Revenue [Member]
Third-party revenue	507	621
Variable Reimbursement Revenue [Member]
Third-party revenue	1,996	1,466
Crude Oil Transportation Revenue [Member]
Third-party revenue	5,331	7,601
Asphalt Terminalling Services [Member]
Third-party revenue	6,982	5,132
Asphalt Terminalling Services [Member] \| Fixed Storage and Throughput Revenue [Member]
Third-party revenue	4,983	3,549
Asphalt Terminalling Services [Member] \| Variable Throughput Revenue [Member]
Third-party revenue	$ 3	117
Revenue, Performance Obligation, Description of Payment Terms	P30D
Asphalt Terminalling Services [Member] \| Variable Reimbursement Revenue [Member]
Third-party revenue	$ 1,996	1,466
Revenue, Performance Obligation, Description of Payment Terms	P30D
Asphalt Terminalling Services [Member] \| Crude Oil Transportation Revenue [Member]
Third-party revenue	$ 0	0
Crude Oil Terminalling Services [Member]
Third-party revenue	3,573	4,585
Crude Oil Terminalling Services [Member] \| Fixed Storage and Throughput Revenue [Member]
Third-party revenue	3,069	4,081
Crude Oil Terminalling Services [Member] \| Variable Throughput Revenue [Member]
Third-party revenue	$ 504	504
Revenue, Performance Obligation, Description of Payment Terms	P30D
Crude Oil Terminalling Services [Member] \| Variable Reimbursement Revenue [Member]
Third-party revenue	$ 0	0
Crude Oil Terminalling Services [Member] \| Crude Oil Transportation Revenue [Member]
Third-party revenue	0	0
Crude Oil Pipeline Services [Member]
Third-party revenue	2,498	2,061
Crude Oil Pipeline Services [Member] \| Fixed Storage and Throughput Revenue [Member]
Third-party revenue	0	0
Crude Oil Pipeline Services [Member] \| Variable Throughput Revenue [Member]
Third-party revenue	0	0
Crude Oil Pipeline Services [Member] \| Variable Reimbursement Revenue [Member]
Third-party revenue	0	0
Crude Oil Pipeline Services [Member] \| Crude Oil Transportation Revenue [Member]
Third-party revenue	$ 2,498	2,061
Revenue, Performance Obligation, Description of Payment Terms	P30D
Crude Oil Pipeline Services [Member] \| Crude Oil Product Sales Revenue [Member]
Revenue, Performance Obligation, Description of Payment Terms	P30D
Crude Oil Trucking Services [Member]
Third-party revenue	$ 2,833	5,540
Crude Oil Trucking Services [Member] \| Fixed Storage and Throughput Revenue [Member]
Third-party revenue	0	0
Crude Oil Trucking Services [Member] \| Variable Throughput Revenue [Member]
Third-party revenue	0	0
Crude Oil Trucking Services [Member] \| Variable Reimbursement Revenue [Member]
Third-party revenue	0	0
Crude Oil Trucking Services [Member] \| Crude Oil Transportation Revenue [Member]
Third-party revenue	$ 2,833	$ 5,540
Revenue, Performance Obligation, Description of Payment Terms	P30D

REVENUE Disaggregation of Reven

REVENUE Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Third-party revenue	$ 15,886	$ 17,318
Third-party revenue, product sales	58,924	3,514
Related-party revenue	4,219	6,321
Revenue from contracts with customers	79,029	27,153
Fixed Storage and Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	8,052	7,630
Related-party revenue	2,931	4,631
Variable Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	507	621
Variable Reimbursement Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	1,996	1,466
Related-party revenue	1,288	1,690
Crude Oil Transportation Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	5,331	7,601
Crude Oil Product Sales Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue, product sales	58,924	3,514
Asphalt Terminalling Services [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	6,982	5,132
Related-party revenue	4,118	6,321
Revenue from contracts with customers	11,100	11,453
Asphalt Terminalling Services [Member] \| Fixed Storage and Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	4,983	3,549
Related-party revenue	2,848	4,631
Asphalt Terminalling Services [Member] \| Variable Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	3	117
Asphalt Terminalling Services [Member] \| Variable Reimbursement Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	1,996	1,466
Related-party revenue	1,270	1,690
Asphalt Terminalling Services [Member] \| Crude Oil Transportation Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0	0
Asphalt Terminalling Services [Member] \| Crude Oil Product Sales Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue, product sales	0	0
Crude Oil Terminalling Services [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	3,573	4,585
Revenue from contracts with customers	3,573	4,585
Crude Oil Terminalling Services [Member] \| Fixed Storage and Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	3,069	4,081
Related-party revenue	0	0
Crude Oil Terminalling Services [Member] \| Variable Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	504	504
Crude Oil Terminalling Services [Member] \| Variable Reimbursement Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0	0
Related-party revenue	0	0
Crude Oil Terminalling Services [Member] \| Crude Oil Transportation Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0	0
Crude Oil Terminalling Services [Member] \| Crude Oil Product Sales Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue, product sales	0	0
Crude Oil Pipeline Services [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	2,498	2,061
Third-party revenue, product sales	58,924	3,508
Related-party revenue	101	0
Revenue from contracts with customers	61,523	5,569
Crude Oil Pipeline Services [Member] \| Fixed Storage and Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0	0
Related-party revenue	83	0
Crude Oil Pipeline Services [Member] \| Variable Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0	0
Crude Oil Pipeline Services [Member] \| Variable Reimbursement Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0	0
Related-party revenue	18	0
Crude Oil Pipeline Services [Member] \| Crude Oil Transportation Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	2,498	2,061
Crude Oil Pipeline Services [Member] \| Crude Oil Product Sales Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue, product sales	58,924	3,508
Crude Oil Trucking Services [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	2,833	5,540
Third-party revenue, product sales	0	6
Revenue from contracts with customers	2,833	5,546
Crude Oil Trucking Services [Member] \| Fixed Storage and Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0	0
Related-party revenue	0	0
Crude Oil Trucking Services [Member] \| Variable Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0	0
Crude Oil Trucking Services [Member] \| Variable Reimbursement Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0	0
Related-party revenue	0	0
Crude Oil Trucking Services [Member] \| Crude Oil Transportation Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	2,833	5,540
Crude Oil Trucking Services [Member] \| Crude Oil Product Sales Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue, product sales	$ 0	$ 6

REVENUE Revenue Related to Futu

REVENUE Revenue Related to Future Performance Obligations Due by Period (Details) $ in Thousands	Mar. 31, 2019USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue related to future performance obligations	$ 124,351
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue related to future performance obligations	30,705
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue related to future performance obligations	29,704
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue related to future performance obligations	25,487
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue related to future performance obligations	18,903
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue related to future performance obligations	11,711
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue related to future performance obligations	$ 7,841

REVENUE Lease Revenue due by Pe

REVENUE Lease Revenue due by Period (Details) $ in Thousands	Mar. 31, 2019USD ($)
Leases [Abstract]
Operating Lease, Lease Income	$ 55,176
Operating Leases, Future Minimum Payments Receivable, in Two Years	52,360
Operating Leases, Future Minimum Payments Receivable, in Three Years	46,637
Operating Leases, Future Minimum Payments Receivable, in Four Years	36,655
Operating Leases, Future Minimum Payments Receivable, in Five Years	24,798
Operating Leases, Future Minimum Payments Receivable, Thereafter	19,220
Operating Leases, Future Minimum Payments Receivable	$ 234,846

RESTRUCTURING CHARGES (Details)

RESTRUCTURING CHARGES (Details) - West Texas Trucking Market Exit Plan [Member] - Crude Oil Trucking Services [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	$ 237	$ 286
Cash payments	$ 49

EQUITY METHOD INVESTMENT (Detai

EQUITY METHOD INVESTMENT (Details) - USD ($) $ in Thousands	Jan. 02, 2018	Apr. 03, 2017	Mar. 31, 2019	Mar. 31, 2018	Sep. 30, 2017
Schedule of Equity Method Investments [Line Items]
Proceeds from sale of unconsolidated affiliate			$ 0	$ 2,225
Gain on sale of unconsolidated affiliate			$ 0	$ 2,225
Advantage Pipeline, L.L.C. [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage		30.00%
Proceeds from sale of unconsolidated affiliate	$ 2,200	$ 25,300			$ 1,100
Gain on sale of unconsolidated affiliate		$ 4,200
Proceeds from Sale of Equity Method Investment, Percent Held In Escrow		10.00%

PROPERTY, PLANT AND EQUIPMENT_2

PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	Jul. 13, 2018	Apr. 24, 2018	Jan. 31, 2019	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property Subject to or Available for Operating Lease, Gross				$ 282,100
Property Subject to or Available for Operating Lease, Accumulated Depreciation				173,300
Property, plant and equipment, gross				511,639		$ 511,815
Accumulated depreciation				268,576		263,554
Property, plant and equipment, net				243,063		248,261
Depreciation				6,000	$ 7,000
Asset impairment expense				1,119	616
Proceeds from sale of assets				6,304	26
Gain (loss) on sale of assets				1,724	(236)
Payments to Acquire Businesses, Gross				0	21,959
Pipelines [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross				117,188		116,155
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross				24,705		24,705
Land improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross				5,798		5,758
Storage and terminal facilities
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross				322,476		321,096
Transportation equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross				1,782		2,798
Office property and equipment and other
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross				27,186		26,980
Pipeline linefill and tank bottoms
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross				8,882		10,297
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross				$ 3,622		4,026
Min \| Pipelines [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)				5 years
Min \| Land improvements
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)				10 years
Min \| Storage and terminal facilities
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)				10 years
Min \| Transportation equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)				3 years
Min \| Office property and equipment and other
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)				3 years
Max \| Pipelines [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)				30 years
Max \| Land improvements
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)				20 years
Max \| Storage and terminal facilities
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)				35 years
Max \| Transportation equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)				10 years
Max \| Office property and equipment and other
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)				20 years
Asphalt Terminalling Services [Member]
Property, Plant and Equipment [Line Items]
Proceeds from Sale of Property Held-for-sale	$ 90,000
Asphalt Terminalling Services [Member] \| Storage and terminal facilities
Property, Plant and Equipment [Line Items]
Asset impairment expense				$ 268
Crude Oil Pipeline Services [Member] \| Pipeline linefill and tank bottoms
Property, Plant and Equipment [Line Items]
Proceeds from sale of assets				2,600
Oklahoma [Member] \| Asphalt Terminalling Services [Member]
Property, Plant and Equipment [Line Items]
Payments to Acquire Businesses, Gross					22,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment					11,500
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles					7,600
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net					$ 2,900
Oklahoma [Member] \| Crude Oil Pipeline Services [Member] \| Pipeline linefill and tank bottoms
Property, Plant and Equipment [Line Items]
Proceeds from sale of assets			$ 1,600
Gain (loss) on sale of assets				200
Texas [Member] \| Crude Oil Trucking Services [Member]
Property, Plant and Equipment [Line Items]
Proceeds from sale of assets				1,600
Gain (loss) on sale of assets				1,481
Proceeds from Sale of Property Held-for-sale		$ 3,000
Gain (Loss) on Disposition of Assets		$ 400
Cimarron Express [Member] \| Ergon [Member]
Property, Plant and Equipment [Line Items]
Other than Temporary Impairment Losses, Investments				$ 800		$ 10,000

DEBT (Credit Agreements) (Detai

DEBT (Credit Agreements) (Details)	3 Months Ended
DEBT (Credit Agreements) (Details)	Mar. 31, 2019USD ($)	Mar. 31, 2018USD ($)	May 06, 2019USD ($)	Dec. 31, 2018USD ($)	Jun. 28, 2018USD ($)
Debt Instrument [Line Items]
Maximum quarterly distribution	$ 10,700,000
Debt issuance costs, noncurrent, net	3,098,000			$ 3,349,000
Amortization of debt issuance costs	251,000	$ 256,000
Interest expense for long-term debt	4,300,000	3,900,000
Long-term Debt, Excluding Current Maturities	252,592,000			$ 265,592,000
Payments under credit agreement	88,000,000	$ 27,000,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Revolving credit facility amount	400,000,000				$ 450,000,000
Maximum borrowing capacity including additional lenders	$ 600,000,000
Debt instrument maximum covenant consolidated senior secured leverage ratio	3.50
Consolidated interest coverage (as a ratio), minimum permitted	2.50
Consolidated total leverage (as a ratio), actual	4.64
Consolidated interest coverage (as a ratio), actual	3.42
Debt instrument, interest rate during period	6.43%	4.96%
Revolving Credit Facility [Member] \| Min
Debt Instrument [Line Items]
Unused capacity, commitment fee (as a percent)	0.375%
Debt instrument covenant, issued qualified senior notes	$ 200,000,000
Revolving Credit Facility [Member] \| Max
Debt Instrument [Line Items]
Unused capacity, commitment fee (as a percent)	0.50%
Revolving Credit Facility [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Revolver borrowings			$ 251,600,000
Unused borrowing capacity			147,400,000
Revolving Credit Facility [Member] \| Federal funds rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	0.50%
Revolving Credit Facility [Member] \| Eurodollar rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	1.00%
Revolving Credit Facility [Member] \| Applicable margin based on ABR [Member] \| Min
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	1.00%
Revolving Credit Facility [Member] \| Applicable margin based on ABR [Member] \| Max
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	2.30%
Revolving Credit Facility [Member] \| Applicable margin based on Eurodollar rate [Member] \| Min
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	2.00%
Revolving Credit Facility [Member] \| Applicable margin based on Eurodollar rate [Member] \| Max
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	3.25%
Letter of Credit [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Letters of credit outstanding			$ 1,000,000
Aggregate Principal Below Threshold [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Minimum acquisition costs	$ 15,000,000
Debt instrument covenant, issued qualified senior notes	200,000,000
Aggregate Principal Above Threshold [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument covenant, issued qualified senior notes	$ 200,000,000
Provision One, Applicable Period One [Member] \| Aggregate Principal Below Threshold [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Consolidated total leverage (as a ratio), maximum permitted	5.25
Provision One, Applicable Period Three [Member] \| Aggregate Principal Below Threshold [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Consolidated total leverage (as a ratio), maximum permitted	5
Provision One, Applicable Period Four [Member] \| Aggregate Principal Below Threshold [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Consolidated total leverage (as a ratio), maximum permitted	4.75
Provision Two, Applicable Period One [Member] \| Aggregate Principal Below Threshold [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Consolidated total leverage (as a ratio), maximum permitted	5.25
Provision Three, Applicable Period One [Member] \| Aggregate Principal Above Threshold [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Consolidated total leverage (as a ratio), maximum permitted	5
Provision Three, Applicable Period Two [Member] \| Aggregate Principal Above Threshold [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Consolidated total leverage (as a ratio), maximum permitted	5.50
Ergon [Member]
Debt Instrument [Line Items]
Credit agreement change of control provision, Ergon minimum control percentage	50.00%
Blueknight General Partners G. P., L.L.C. [Member]
Debt Instrument [Line Items]
Credit agreement change of control provision, General Partner ownership minimum	100.00%

DEBT Derivative Instruments (De

DEBT Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Jan. 28, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest Income, Other	$ 100
Document Period End Date	Mar. 31, 2019
Interest Rate Swaps, Notional Amount	$ 0
Notional Amount, Expired			$ 100,000
Interest Expense, Other		$ 100
Unrealized Gain (Loss) on Interest Rate Swaps	$ (44)	$ 354
Other Current Assets [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest Rate Swap Assets - Current				$ 44

NET INCOME PER LIMITED PARTNE_3

NET INCOME PER LIMITED PARTNER UNIT (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share [Abstract]
Net income	$ 3,757	$ 4,442
General partner interest in net income	105	231
Preferred interest in net income	6,279	6,278
Net income (loss) available to limited partners	$ (2,627)	$ (2,067)
Basic and diluted weighted average number of units:
Common units	40,678	40,289
Weighted Average Restricted and Phantom Partnership Units Outstanding, Basic and Diluted	769	833
Total Weighted Average Limited Partnership Units Outstanding, Basic and Diluted	41,447	41,122
Basic and diluted net income (loss) per common unit	$ (0.06)	$ (0.05)

PARTNERS' CAPITAL AND DISTRIB_2

PARTNERS' CAPITAL AND DISTRIBUTIONS Cash Distributions Paid on Preferred Units (Details) - Preferred Units [Member] $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)$ / shares
Preferred and General Partners [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Cash Distributions Declared	$ 6.4
Preferred Partner [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Distributions Declared, Per Unit \| $ / shares	$ 0.17875
Distribution Made to Limited Partner, Cash Distributions Declared	$ 6.3
General Partner [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Cash Distributions Declared	$ 0.1

PARTNERS' CAPITAL AND DISTRIB_3

PARTNERS' CAPITAL AND DISTRIBUTIONS Cash Distributions Paid on Common Units (Details) - Common Units [Member] $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)$ / shares
Limited, General Partner, Phantom Share and Restricted Units [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Cash Distributions Declared	$ 1.7
Limited Partner [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Distributions Declared, Per Unit \| $ / shares	$ 0.0400
Distribution Made to Limited Partner, Cash Distributions Declared	$ 1.6
General Partner [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Cash Distributions Declared	0.1
Phantom Share Units and Restricted Units [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Cash Distributions Declared	$ 0.1

RELATED PARTY TRANSACTIONS (Det

RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Related Party Transaction [Line Items]
Receivables from related parties	$ 936		$ 1,043
Accrued crude oil purchases to related parties	11,885		10,219
Ergon [Member]
Related Party Transaction [Line Items]
Related-party revenue	9,100	$ 14,000
Receivables from related parties	900		1,000
Payables to Related Parties	16,800		$ 6,500
Crude Oil Purchase Agreement [Member] \| Ergon [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Purchases from Related Party	30,000
Accrued crude oil purchases to related parties	$ 11,900

RELATED PARTY TRANSACTIONS Cima

RELATED PARTY TRANSACTIONS Cimarron Transactions (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 30, 2019	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Related Party Transaction [Line Items]
Payments to Acquire Property, Plant, and Equipment		$ 2,801	$ 4,563
Fixed asset impairment charge		$ 1,119	$ 427
Potential Equity Method Ownership Percentage				50.00%
Cimarron Express [Member]
Related Party Transaction [Line Items]
Payments to Acquire Property, Plant, and Equipment				$ 30,600
Fixed asset impairment charge				20,900
Devco Purchase Agreement [Member] \| Ergon [Member]
Related Party Transaction [Line Items]
Joint Venture Purchase Option		100.00%
Cimarron Express [Member] \| Ergon [Member]
Related Party Transaction [Line Items]
Other than Temporary Impairment Losses, Investments		$ 800		10,000
Cimarron Express [Member] \| Ergon [Member]
Related Party Transaction [Line Items]
Payments to Acquire Equity Method Investments				17,800
Other than Temporary Impairment Losses, Investments				$ 10,000
Subsequent Event [Member] \| Cimarron Express [Member]
Related Party Transaction [Line Items]
Gain (Loss) on Disposition of Assets	$ 1,400
Cimarron Express [Member] \| Ergon [Member]
Related Party Transaction [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent		50.00%

LONG-TERM INCENTIVE PLAN (Detai

LONG-TERM INCENTIVE PLAN (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended								3 Months Ended
		Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017		Mar. 31, 2017	Dec. 31, 2016		Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based incentive compensation expense (in dollars)										$ 69	$ 41
Blueknight Energy Partners G.P., L.L.C. Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units authorized		4,100,000								4,100,000
Number of Units [Roll Forward]
Nonvested at December 31, 2018										998,219
Granted										524,997
Vested										366,282
Forfeited										0
Nonvested at March 31, 2019		1,156,934	998,219							1,156,934
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Nonvested, Beginning balance (in dollars per unit)										$ 5.88
Weighted Average Grant Date Fair Value, Granted (in dollars per unit)										1.14
Weighted Average Grant Date Fair Value, Vested (in dollars per unit)										4.80
Weighted Average Grant Date Fair Value, Forfeited (in dollars per unit)										0
Weighted Average Grant Date Fair Value, Nonvested, Ending balance (in dollars per unit)		$ 3.60	$ 5.88							$ 3.60
Blueknight Energy Partners G.P., L.L.C. Long-Term Incentive Plan [Member] \| Common Stock [Member] \| Independent Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Value of award grants (in dollars)			$ 26		$ 69			$ 70
Number of Units [Roll Forward]
Granted			21,875		14,286			10,220
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Granted (in dollars per unit)			$ 1.20		$ 4.85	[1]		$ 6.85	[1]
Blueknight Energy Partners G.P., L.L.C. Long-Term Incentive Plan [Member] \| Phantom common units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized estimated compensation cost (in dollars)		$ 1,700								$ 1,700
Equity-based incentive compensation expense (in dollars)										$ 300	$ 500
Blueknight Energy Partners G.P., L.L.C. Long-Term Incentive Plan [Member] \| Restricted common units [Member] \| Independent Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period										3 years
Value of award grants (in dollars)			$ 28		$ 74			$ 75
Number of Units [Roll Forward]
Granted			23,436		15,306			10,950
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Granted (in dollars per unit)			$ 1.20		$ 4.85	[1]		$ 6.85	[2]
January 2020 Vesting [Member] \| Blueknight Energy Partners G.P., L.L.C. Long-Term Incentive Plan [Member] \| Phantom common units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Value of award grants (in dollars)							$ 2,312
Number of Units [Roll Forward]
Granted							323,339
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Granted (in dollars per unit)	[3]						$ 7.15
January 2021 Vesting [Member] \| Blueknight Energy Partners G.P., L.L.C. Long-Term Incentive Plan [Member] \| Phantom common units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Value of award grants (in dollars)				$ 2,185
Number of Units [Roll Forward]
Granted				457,984
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Granted (in dollars per unit)	[3]			$ 4.77
January 2022 Vesting [Member] \| Blueknight Energy Partners G.P., L.L.C. Long-Term Incentive Plan [Member] \| Phantom common units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Value of award grants (in dollars)		$ 598
Number of Units [Roll Forward]
Granted		524,997
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Granted (in dollars per unit)	[3]	$ 1.14

[1]	Fair value is the closing market price on the grant date of the awards.
[2]	Fair value is the closing market price on the grant date of the awards.
[3]	Fair value is the closing market price on the grant date of the awards.

EMPLOYEE BENEFIT PLAN (Details)

EMPLOYEE BENEFIT PLAN (Details) - Blueknight Energy Partners G.P., L.L.C. 401(K) Plan [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Pension Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Employer discretionary contribution amount	$ 0.3	$ 0.3
Other Postretirement Benefits Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Employer discretionary contribution amount	$ 0.2	$ 0.1

EMPLOYEE BENEFIT PLAN EUPP (Det

EMPLOYEE BENEFIT PLAN EUPP (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
EUPP [Abstract]
Employee Stock Ownership Plan (ESOP), Shares in ESOP	1,000,000
Employee Stock Ownership Plan (ESOP), Compensation Expense	$ 0.1	$ 0.1

FAIR VALUE MEASUREMENTS Fair _2

FAIR VALUE MEASUREMENTS Fair Value Measurements (Details) $ in Thousands	Dec. 31, 2018USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap assets	$ 44
Total swap assets	44
Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap assets	0
Total swap assets	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap assets	44
Total swap assets	44
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap assets	0
Total swap assets	$ 0

LEASES (Details)

LEASES (Details) - USD ($)	3 Months Ended
LEASES (Details) - USD ($)	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Operating Lease, Right-of-Use Asset	$ 11,594,000		$ 0
Finance Lease, Right-of-Use Asset	631,000
Right of Use Lease Assets, Total	12,225,000
Current operating lease liability	2,768,000		0
Finance Lease, Liability, Current	263,000
Noncurrent operating lease liability	8,935,000		$ 0
Finance Lease, Liability, Noncurrent	368,000
Lease Liabilities, Total	12,334,000
Operating lease cost	1,142,000
Amortization of leased assets	70,000
Finance Lease, Interest Expense	7,000
Net lease cost	1,219,000
Operating cash flows from operating leases	(750,000)
Operating cash flows from finance leases	(66,000)
Interest on lease liabilities	(12,000)
Leased assets obtained in exchange for new operating lease liabilities	569,000
Leased assets obtained in exchange for new finance lease liabilities	$ 112,000
Operating leases, Weighted Average Remaining Lease Term	9 years
Finance leases, Weighted Average Remaining Lease Term	2 years 9 months 2 days
Operating leases, Weighted Average Discount Rate, Percent	5.65%
Finance lease, Weighted Average Discount Rate, Percent	4.20%
Operating Lease, Liability	$ 11,703,000
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset		$ 11,800,000
Operating Lease, Liability		$ 11,900,000

LEASES Leases, Maturity of Leas

LEASES Leases, Maturity of Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months	$ 2,993	$ 2,862
Lessee, Operating Lease, Liability, Payments, Due Year Two	2,447	1,904
Lessee, Operating Lease, Liability, Payments, Due Year Three	1,843	1,242
Lessee, Operating Lease, Liability, Payments, Due Year Four	1,413	640
Lessee, Operating Lease, Liability, Payments, Due Year Five	1,199	548
Lessee, Operating Lease, Liability, Payments, Due after Year Five	5,208	1,259
Lessee, Operating Lease, Liability, Payments, Due	15,103
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	3,400
Operating Leases, Future Minimum Payments Due		$ 8,455
Operating Lease, Liability	11,703
Finance Lease, Liability, Payments, Remainder of Fiscal Year	285
Finance Lease, Liability, Payments, Due Year Two	215
Finance Lease, Liability, Payments, Due Year Three	129
Finance Lease, Liability, Payments, Due Year Four	42
Finance Lease, Liability, Payments, Due Year Five	0
Finance Lease, Liability, Payments, Due after Year Five	0
Finance Lease, Liability, Payments, Due	671
Finance Lease, Liability, Undiscounted Excess Amount	40
Finance Lease, Liability	$ 631

OPERATING SEGMENTS (Details)

OPERATING SEGMENTS (Details) $ in Thousands	3 Months Ended
OPERATING SEGMENTS (Details) $ in Thousands	Mar. 31, 2019USD ($)Operating-segmentsTerminalling_And_Storage_Facilities	Mar. 31, 2018USD ($)	Dec. 31, 2018USD ($)
Segment Reporting Information [Line Items]
Document Period End Date	Mar. 31, 2019
Number of operating segments (in operating segments) \| Operating-segments	4
Service revenue
Third-party revenue	$ 15,886	$ 17,318
Sales revenue from related parties, services, net	4,219	6,321
Lease revenue:
Third-party revenue	9,763	9,804
Related-party revenue	4,940	7,703
Product sales revenue:
Third-party revenue	58,924	3,514
Total revenue for reportable segments	93,732	44,660
Cost of product sales from related party	24,587	2,637
Cost of product sales	30,774	0
Operating margin, excluding depreciation and amortization	17,862	18,255
Total assets (end of period)	319,656		$ 323,304
Reconciles segment operating margin (excluding depreciation and amortization) to income before income taxes
Operating margin, excluding depreciation and amortization	17,862	18,255
Depreciation and amortization	(6,734)	(7,367)
General and administrative expense	(3,693)	(4,221)
Asset impairment expense	(1,119)	(616)
Gain (loss) on sale of assets	1,724	(236)
Interest expense	(4,271)	(3,569)
Gain on sale of unconsolidated affiliate	0	2,225
Income before income taxes	$ 3,769	4,471
Asphalt Terminalling Services [Member]
Segment Reporting Information [Line Items]
Number of terminalling and storage facilities providing asphalt product and residual fuel terminalling storage and blending services (in terminalling and storage facilities) \| Terminalling_And_Storage_Facilities	53
Service revenue
Third-party revenue	$ 6,982	5,132
Sales revenue from related parties, services, net	4,118	6,321
Lease revenue:
Third-party revenue	9,763	9,458
Related-party revenue	4,940	7,702
Product sales revenue:
Total revenue for reportable segments	25,803	28,613
Operating expenses (excluding depreciation and amortization)	12,285	13,333
Operating margin, excluding depreciation and amortization	13,518	15,280
Total assets (end of period)	147,844	170,473
Reconciles segment operating margin (excluding depreciation and amortization) to income before income taxes
Operating margin, excluding depreciation and amortization	$ 13,518	15,280
Number of states where Asphalt terminalling and storage facilities are located \| Terminalling_And_Storage_Facilities	26
Crude Oil Terminalling Services [Member]
Service revenue
Third-party revenue	$ 3,573	4,585
Intersegment Revenues	298	0
Lease revenue:
Third-party revenue	0	15
Product sales revenue:
Total revenue for reportable segments	3,871	4,600
Operating expenses (excluding depreciation and amortization)	1,282	1,275
Operating margin, excluding depreciation and amortization	2,589	3,325
Total assets (end of period)	67,934	68,160
Reconciles segment operating margin (excluding depreciation and amortization) to income before income taxes
Operating margin, excluding depreciation and amortization	2,589	3,325
Crude Oil Pipeline Services [Member]
Service revenue
Third-party revenue	2,498	2,061
Sales revenue from related parties, services, net	101	0
Lease revenue:
Third-party revenue	0	235
Product sales revenue:
Third-party revenue	58,924	3,508
Total revenue for reportable segments	61,523	5,804
Operating expenses (excluding depreciation and amortization)	2,722	2,785
Intersegment operating expenses	1,627	442
Cost of product sales from related party	24,587	2,637
Cost of product sales	30,774	0
Operating margin, excluding depreciation and amortization	1,813	(60)
Total assets (end of period)	98,722	116,845
Reconciles segment operating margin (excluding depreciation and amortization) to income before income taxes
Operating margin, excluding depreciation and amortization	1,813	(60)
Crude Oil Trucking Services [Member]
Service revenue
Third-party revenue	2,833	5,540
Intersegment Revenues	1,329	442
Lease revenue:
Third-party revenue	0	97
Product sales revenue:
Third-party revenue	0	6
Total revenue for reportable segments	4,162	6,085
Operating expenses (excluding depreciation and amortization)	4,220	6,375
Operating margin, excluding depreciation and amortization	(58)	(290)
Total assets (end of period)	5,156	6,113
Reconciles segment operating margin (excluding depreciation and amortization) to income before income taxes
Operating margin, excluding depreciation and amortization	(58)	(290)
Operating Segments [Member]
Service revenue
Intersegment Revenues	(1,627)	(442)
Product sales revenue:
Total revenue for reportable segments	$ 95,359	$ 45,102

INCOME TAXES (Details)

INCOME TAXES (Details) $ in Thousands	Mar. 31, 2019USD ($)
Valuation Allowance [Line Items]
Difference in bases of property, plant and equipment	$ 260
Deferred tax asset, operating loss carryforwards	7
Deferred tax asset	267
Less: valuation allowance	267
Net deferred tax asset	$ 0