Blueknight Energy Partners (BKEP) 10-K 12 Mar 19 2018 Q4 Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Mar. 01, 2019	Jun. 30, 2018	Dec. 31, 2017
Entity Information [Line Items]
Preferred 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 Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Public Float			$ 137.1
Entity Common Stock, Shares Outstanding		40,714,857
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q4
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2018

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 1,455	$ 2,469
Accounts receivable, net of allowance for doubtful accounts of $28 and $26 at December 31, 2017 and 2018, respectively	35,683	7,589
Receivables from related parties, net of allowance for doubtful accounts of $0 at both dates	1,043	3,070
Prepaid insurance	1,860	2,009
Other current assets	7,485	8,438
Total current assets	47,526	23,575
Assets, Noncurrent [Abstract]
Property, plant and equipment, net of accumulated depreciation of $316,591 and $282,402 at December 31, 2017 and 2018, respectively	248,261	296,069
Goodwill	6,728	3,870
Debt issuance costs, net	3,349	4,442
Intangibles and other assets, net	17,440	12,913
Total assets	323,304	340,869
Current liabilities:
Accounts payable	3,707	4,439
Accounts payable to related parties	2,263	2,268
Accrued crude oil purchases	13,949	1,115
Accrued crude oil purchases to related parties	10,219	0
Contingent liability with related party (Note 14)	10,019	0
Accrued interest payable	465	694
Accrued property taxes payable	3,089	2,432
Unearned revenue	3,206	2,393
Unearned revenue with related parties	4,835	551
Accrued payroll	3,667	6,119
Other current liabilities	3,465	3,632
Total current liabilities	48,865	23,643
Liabilities, Noncurrent [Abstract]
Long-term unearned revenue with related parties	1,714	1,052
Other long-term liabilities	0	225
Long-term interest rate swap liabilities	4,010	3,673
Long-term debt	265,592	307,592
Commitments and contingencies (Note 18)
Partners’ capital:
Common unitholders (40,158,342 and 40,424,372 units issued and outstanding at December 31, 2017 and 2018, respectively)	253,923	253,923
Preferred Units (35,125,202 units issued and outstanding at both dates)	370,972	454,358
General partner interest (1.6% interest with 1,225,409 general partner units outstanding at both dates)	(631,791)	(703,597)
Total partners’ capital	(6,896)	4,684
Total liabilities and partners’ capital	$ 323,304	$ 340,869

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Accounts receivable, allowance for doubtful accounts	$ 26	$ 28
Receivables from related parties, allowance for doubtful accounts	0	0
Assets, Noncurrent [Abstract]
Property, plant and equipment, accumulated depreciation and impairments	$ 263,554	$ 316,591
Partners’ capital:
Preferred unitholders, units issued	35,125,202	35,125,202
Preferred unitholders, units outstanding	35,125,202	35,125,202
Common unitholders, units issued	40,424,372	40,158,342
Common unitholders, units outstanding	40,424,372	40,158,342
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	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Service revenue:
Third-party revenue	$ 58,756	$ 113,772	$ 126,215
Related-party revenue	22,131	56,688	30,211
Lease Revenue:
Third-party revenue	42,067	0	0
Related-party revenue	25,961	0	0
Product sales revenue:
Third-party revenue	235,438	11,479	20,968
Related-party revenue	482	0	0
Total revenue	384,835	181,939	177,394
Costs and expenses:
Operating expense	113,890	123,805	111,091
Cost of product sales	126,776	8,807	14,130
Cost of product sales from related party	102,469	0	0
General and administrative expense	15,995	17,112	20,029
Asset impairment expense	53,068	2,400	25,761
Total costs and expenses	412,198	152,124	171,011
Gain (loss) on sale of assets	149	(975)	108
Operating income	(27,214)	28,840	6,491
Other income (expenses):
Equity earnings in unconsolidated affiliate	0	61	1,483
Gain on sale of unconsolidated affiliate	2,225	5,337	0
Interest expense	(16,860)	(14,027)	(12,554)
Income (loss) before income taxes	(41,849)	20,211	(4,580)
Provision for income taxes	198	166	260
Net income (loss)	(42,047)	20,045	(4,840)
Allocation of net income for calculation of earnings per unit:
General partner interest in net income	(512)	944	433
Preferred interest in net income	25,115	25,115	25,824
Net loss available to limited partners	$ (66,650)	$ (6,014)	$ (31,097)
Basic and diluted net loss per common unit	$ (1.61)	$ (0.15)	$ (0.87)
Weighted average common units outstanding - basic and diluted	40,348	38,342	35,093

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN PARTNERS' CAPITAL - USD ($) $ in Thousands	Total	Preferred Partner [Member]	Limited Partner [Member]	General Partner [Member]
Balance at Dec. 31, 2015	$ 87,219	$ 204,599	$ 493,824	$ (611,204)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(4,840)	24,939	(30,004)	225
Equity-based incentive compensation	2,087		2,051	36
Profits interest contribution	923			923
Distributions	(47,219)	(24,939)	(20,960)	1,320
Capital contributions	2,384			2,384
Proceeds from sale of 3,795,000 common units, net of underwriters’ discount and offering expenses of $1.5 million	20,931		20,931
Proceeds from sale of common units pursuant to the Employee Unit Purchase Plan	338		338
Repurchase of 13,335,390 Preferred Units	(95,348)	(95,348)
Proceeds from issuance of 18,312,968 Preferred Units	144,672
Proceeds from issuance of common units in private placement	5,000		5,000
Proceeds from issuance of 97,654 general partner units	680			680
Consideration paid in excess of historical cost of assets acquired from Ergon	(91,251)			(91,251)
Balance at Dec. 31, 2016	25,576	253,923	471,180	(699,527)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	20,045	25,116	(6,009)	938
Equity-based incentive compensation	1,451		1,424	27
Distributions	(49,163)	(25,116)	(22,633)	(1,414)
Capital contributions	104			104
Proceeds from sale of common units pursuant to the Employee Unit Purchase Plan	240		240
Repurchase of 13,335,390 Preferred Units	0
Value of stock issued during period for acquisitions	10,156
Consideration paid in excess of historical cost of assets acquired from Ergon	(3,725)			(3,725)
Balance at Dec. 31, 2017	4,684	253,923	454,358	(703,597)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(42,047)	25,115	(66,818)	(344)
Equity-based incentive compensation	1,845		1,811	34
Distributions	(44,736)	(25,115)	(18,587)	(1,034)
Capital contributions	183			183
Capital Contribution Related to Sale of Assets to Entity Under Common Control	72,967			72,967
Proceeds from sale of common units pursuant to the Employee Unit Purchase Plan	208		208
Repurchase of 13,335,390 Preferred Units	0
Balance at Dec. 31, 2018	$ (6,896)	$ 253,923	$ 370,972	$ (631,791)

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN PARTNERS' CAPITAL (Parenthetical) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Limited Partner [Member]
Partners' capital account, units issued			3,795,000
Underwriters’ discount and offering expenses on common units			$ 1,500,000
Common units issued for acquisitions			847,457
Common units issued, Employee Unit Purchase Plan	61,327	53,079	71,807
Common units issued for acquisitions		1,898,380
General Partner [Member]
Partners' capital account, units issued			97,654
Preferred Partner [Member]
Partners' capital account, units issued			18,312,968
Preferred Units repurchased			13,335,390

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net income (loss)	$ (42,047)	$ 20,045	$ (4,840)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Provision for uncollectible receivables from third parties	(2)	(21)	15
Provision for uncollectible receivables from related parties	0	0	(229)
Depreciation and amortization	29,359	31,139	30,820
Intangible asset impairment charge	189	1,107	0
Amortization and write-off of debt issuance costs	1,451	1,816	1,107
Unrealized gain related to interest rate swaps	(201)	(1,790)	(1,156)
Fixed asset impairment charge	42,860	1,293	25,761
Other Asset Impairment Charges	10,019	0	0
Loss (gain) on sale of assets	(149)	975	(108)
Gain on sale of unconsolidated affiliate	(2,225)	(5,337)	0
Equity-based incentive compensation	1,845	1,451	2,087
Equity earnings in unconsolidated affiliate	0	(61)	(1,483)
Changes in assets and liabilities:
Decrease (increase) in accounts receivable	(25,450)	(24)	1,138
Decrease (increase) in receivables from related parties	2,027	(1,210)	213
Decrease in prepaid insurance	2,085	2,507	3,008
Decrease (increase) in other current assets	1,314	(983)	237
Decrease (increase) in other non-current assets	442	84	(498)
Increase (decrease) in accounts payable	(592)	952	(237)
Increase in payables to related parties	342	749	1,053
Increase (Decrease) in Other Current Liabilities	13,949	0	0
Increase (Decrease) in Due to Other Related Parties, Current	10,219	0	0
Increase (decrease) in accrued interest payable	(229)	281	222
Increase (decrease) in accrued property taxes	1,031	(72)	(242)
Increase (decrease) in unearned revenue	785	898	(1,568)
Increase in unearned revenue from related parties	5,714	580	187
Decrease in accrued payroll	(2,452)	(239)	(905)
Increase (decrease) in other accrued liabilities	(1,500)	354	(1,733)
Net cash provided by operating activities	48,784	54,494	52,849
Cash flows from investing activities:
Acquisition of assets from Ergon	0	0	(122,572)
Acquisitions	(21,959)	0	(18,989)
Capital expenditures	(34,400)	(18,715)	(19,995)
Proceeds from sale of assets	5,051	9,297	1,993
Proceeds from sale of terminal assets to Ergon	88,538	0	0
Proceeds from sale of unconsolidated affiliate	2,225	26,489	0
Net cash provided by (used in) investing activities	39,455	17,071	(159,563)
Cash flows from financing activities:
Payment on insurance premium financing agreement	(2,399)	(2,965)	(3,425)
Repayments of Long-term Capital Lease Obligations	(151)	0	0
Debt issuance costs	(358)	(4,208)	(956)
Borrowings under credit agreement	324,000	378,592	170,000
Payments under credit agreement	366,000	395,000	91,000
Proceeds from issuance of common units, net of offering costs	208	240	26,269
Proceeds from issuance of Preferred Units	0	0	144,672
Proceeds from issuance of general partner units	0	0	680
Repurchase of Preferred Units	0	0	(95,348)
Capital contributions	183	104	2,384
Capital contributions related to profits interest	0	0	923
Distributions	(44,736)	(49,163)	(47,219)
Net cash provided by (used in) financing activities	(89,253)	(72,400)	106,980
Net increase (decrease) in cash and cash equivalents	(1,014)	(835)	266
Cash and cash equivalents at beginning of period	2,469	3,304	3,038
Cash and cash equivalents at end of period	1,455	2,469	3,304
Supplemental disclosure of non-cash financing and investing cash flow information:
Assets acquired through non-cash equity issuance	0	10,156	0
Non-cash changes in property, plant and equipment	(715)	779	(1,825)
Non-cash change in assets and liabilities due to settlement items related to the sale of terminal assets to Ergon	(1,308)	0	0
Increase in accrued liabilities related to insurance premium financing agreement	2,184	2,938	3,189
Cash paid for interest, net of amounts capitalized	16,088	13,732	12,404
Cash paid for income taxes	$ 133	$ 158	$ 282

ORGANIZATION AND NATURE OF BUSI

ORGANIZATION AND NATURE OF BUSINESS	12 Months Ended
	Dec. 31, 2018
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 and transportation services for companies engaged in the production, distribution and marketing of liquid asphalt and crude oil. 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. On April 24, 2018, the Partnership sold the producer field services business. As a result of the sale of the producer field services business, the Partnership changed the name of the crude oil trucking and producer field services operating segment to crude oil trucking services during the second quarter of 2018. See Note 8 for additional information. 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. On October 5, 2016, the Partnership completed the following transactions (the “Ergon Transactions”): (i) a subsidiary of Ergon, Inc. (together with its subsidiaries, “Ergon”) purchased 100% of the outstanding voting stock of Blueknight GP Holding, L.L.C., which owns 100% of the capital stock of the Partnership’s general partner, Blueknight Energy Partners G.P., L.L.C., pursuant to a Membership Interest Purchase Agreement dated July 19, 2016, among CB-Blueknight, LLC, an indirect wholly-owned subsidiary of Charlesbank, Blueknight Energy Holding, Inc., an indirect wholly-owned subsidiary of Vitol Holding B.V. (together with its affiliates and subsidiaries “Vitol”), and Ergon Asphalt Holdings, LLC, a wholly-owned subsidiary of Ergon (the “Ergon Change of Control”); (ii) Ergon contributed nine asphalt terminals plus $22.1 million in cash in return for total consideration of approximately $144.7 million , which consisted of the issuance of 18,312,968 of Preferred Units in a private placement; and (iii) Ergon acquired an aggregate of $5.0 million of common units for cash in a private placement, pursuant to a Contribution Agreement between the Partnership and Ergon. In addition, the Partnership repurchased 6,667,695 Preferred Units from each Vitol and Charlesbank for an aggregate purchase price of approximately $95.3 million . Vitol and Charlesbank each retained 2,488,789 Preferred Units upon completion of these transactions The Partnership’s acquisition of nine asphalt terminals from Ergon on October 5, 2016, was accounted for as a transaction among entities under common control. As a result, the Partnership recorded the acquired assets at Ergon’s historical cost of $31.3 million , net of accumulated depreciation of $63.0 million . The $91.3 million of consideration in excess of Ergon’s historical net book value was recorded as a deemed distribution to the Partnership’s general partner and is reflected as “Consideration paid in excess of historical cost of assets acquired from Ergon” on the Partnership’s consolidated statement of changes in partners’ capital.

BASIS OF CONSOLIDATION AND PRES

BASIS OF CONSOLIDATION AND PRESENTATION	12 Months Ended
	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
BASIS OF CONSOLIDATION AND PRESENTATION	BASIS OF CONSOLIDATION AND PRESENTATION The accompanying consolidated financial statements and related notes present and discuss the Partnership’s consolidated financial position as of December 31, 2017 and 2018 , and the consolidated results of the Partnership’s operations, cash flows and changes in partners’ capital for the years ended December 31, 2016 , 2017 and 2018 . The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”). All significant intercompany accounts and transactions have been eliminated in the preparation of the accompanying consolidated financial statements. Certain reclassifications have been made to the prior period consolidated financial statements to conform to the current period presentation.

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Significant Accounting Policies [Text Block]	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES USE OF ESTIMATES - The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and disclosure of contingencies. Management makes significant estimates including: (1) allowance for doubtful accounts receivable; (2) estimated useful lives of assets, which impacts depreciation; (3) estimated cash flows and fair values inherent in impairment tests; (4) accruals related to revenues and expenses; (5) the estimated fair value of financial instruments; and (6) liability and contingency accruals. Although management believes these estimates are reasonable, actual results could differ from these estimates. CASH AND CASH EQUIVALENTS - Cash and cash equivalents includes cash and all investments with original maturities of three months or less which are readily convertible into known amounts of cash. ACCOUNTS RECEIVABLE - The majority of the Partnership’s accounts receivable relates to its crude oil pipeline services segment, specifically the crude oil marketing business. Accounts receivable included in the consolidated balance sheets are reflected net of the allowance for doubtful accounts of less than $0.1 million at both December 31, 2017 and 2018 . The Partnership reviews all outstanding accounts receivable balances on a monthly basis and records a reserve for amounts that the Partnership expects will not be fully recovered. Although the Partnership considers its allowance for doubtful trade accounts receivable to be adequate, there is no assurance that actual amounts will not vary significantly from estimated amounts. PROPERTY, PLANT AND EQUIPMENT - Property, plant and equipment are recorded at cost. Expenditures for maintenance and repairs that do not add capacity or extend the useful life of an asset are expensed as incurred. The carrying values of the assets are based on estimates, assumptions and judgments relative to useful lives and salvage values. As assets are disposed of, the cost and related accumulated depreciation are removed from the accounts, and any resulting gain or loss is included in operating income in the consolidated statements of operations. Depreciation is calculated using the straight-line method based on estimated useful lives of the assets. These estimates are based on various factors, including age (in the case of acquired assets), manufacturing specifications, technological advances and historical data concerning useful lives of similar assets. Uncertainties that impact these estimates include changes in laws and regulations relating to restoration and abandonment requirements, economic conditions and supply and demand in the area. When assets are put into service, management makes estimates with respect to useful lives and salvage values that it believes are reasonable. However, subsequent events could cause management to change its estimates, thus impacting the future calculation of depreciation. The Partnership has contractual obligations to perform dismantlement and removal activities in the event that some of its liquid asphalt cement and residual fuel oil terminalling assets are abandoned (see Note 18 ). Such obligations are recognized in the period incurred if reasonably estimable. IMPAIRMENT OF LONG-LIVED ASSETS AND OTHER INTANGIBLE ASSETS - Long-lived assets with recorded values that are not expected to be recovered through future cash flows are written down to estimated fair value. A long-lived asset is tested for impairment when events or circumstances indicate that its carrying value may not be recoverable. The carrying value of a long-lived asset is not recoverable if it exceeds the sum of the undiscounted cash flows expected to result from the use and eventual disposition of the asset. If the carrying value exceeds the sum of the undiscounted cash flows, an impairment loss equal to the amount by which the carrying value exceeds the fair value of the asset is recognized. Fair value is generally determined from estimated discounted future net cash flows. During the year ended December 31, 2018 , the Partnership recognized fixed asset impairment expenses of approximately $40.7 million related to a markdown of our pipeline system to estimated fair value, $1.7 million related to the market value of its pipeline linefill assets and $0.4 million related to the value of obsolete trucking stations in Oklahoma and Colorado. In addition, the Partnership recognized a $10.0 million impairment on a push-down basis related to Ergon’s investment in Cimarron Pipeline. See Note 14 for more information. During the year ended December 31, 2017 , the Partnership recognized fixed asset impairment charges of $1.2 million related to the producer field services business, primarily operated in the Texas panhandle. During the year ended December 31, 2016 , the Partnership recognized fixed asset impairment charges of $25.8 million , primarily due to impairment recognized on the Knight Warrior pipeline project and the East Texas pipeline system. The Knight Warrior pipeline project was canceled due to continued low rig counts in the Eaglebine/Woodbine area coupled with lower production volumes, competing projects and the overall impact of the decreased market price of crude oil. Consequently, shipper commitments related to the project were canceled and an impairment expense of $22.6 million was recognized during the year ended December 31, 2016 . Acquired customer relationships are capitalized and amortized over useful lives ranging from 5 to 20 years using the straight-line method of amortization. An impairment loss is recognized for definite-lived intangibles if the carrying amount of an intangible asset is not recoverable and its carrying amount exceeds its fair value. No impairment charges were recognized during the year ended December 31, 2016 , with respect to intangible assets. During the year ended December 31, 2017 , the Partnership recognized intangible asset impairment charges of $0.2 million on customer relationships related to the former producer field services business, primarily operated in the Texas panhandle. During the year ended December 31, 2018 , the Partnership recognized intangible asset impairment charges of $0.2 million related to a customer contract asset in the crude oil pipeline services business. Intangible asset impairment charges are included in the line item “Asset impairment expense” on the consolidated statements of operations. EQUITY METHOD INVESTMENTS - The Partnership’s approximate 30% ownership 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 its equity method investee. 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’s share of net income or loss is reflected as one line item on the Partnership’s consolidated statements of operations entitled “Equity earnings in unconsolidated affiliate” and increased or decreased, as applicable, the carrying value of the Partnership’s investment in the unconsolidated affiliate on the consolidated balance sheets. Distributions to the Partnership reduced the carrying value of its investment and are reflected in the Partnership’s consolidated statements of cash flows in the line item “Distributions from unconsolidated affiliate.” In turn, contributions increased the carrying value of the Partnership’s investment and were reflected in the Partnership’s consolidated statements of cash flows in investing activities. See Note 6 for additional information. DEBT ISSUANCE COSTS - Costs incurred in connection with the issuance of long-term debt related to the Partnership’s credit agreement are capitalized and amortized using the straight-line method over the term of the related debt. Use of the straight-line method does not differ materially from the “effective interest” method of amortization. GOODWILL - Goodwill represents the excess of the cost of acquisitions over the amounts assigned to assets acquired and liabilities assumed. Goodwill is not amortized but is tested annually in December for impairment or when events and circumstances warrant an interim evaluation. Goodwill is tested for impairment at a level of reporting referred to as a reporting unit. The Partnership has four reporting units comprised of its (i) asphalt terminalling services, (ii) crude oil terminalling services, (iii) crude oil pipeline services and (iv) crude oil trucking services. If the fair value of a reporting unit exceeds its carrying amount, goodwill of the reporting unit is not considered to be impaired. The impairment test is generally based on the estimated discounted future net cash flows of the respective reporting unit, utilizing discount rates and other factors in determining the fair value of the reporting unit. Inputs in the Partnership’s estimated discounted future net cash flows include existing and estimated future asset utilization, estimated growth rates in future cash flows and estimated terminal values (these are all considered Level 3 inputs). Changes in the carrying amount of goodwill are summarized below for the periods indicated (in thousands): Asphalt Terminalling Services Crude Oil Trucking Services Total Balance, December 31, 2015 $ 3,511 $ 876 $ 4,387 Acquisition 359 — 359 Balance, December 31, 2016 $ 3,870 $ 876 $ 4,746 Impairment — (876 ) (876 ) Balance, December 31, 2017 $ 3,870 $ — $ 3,870 Acquisition 2,858 — 2,858 Balance, December 31, 2018 $ 6,728 $ — $ 6,728 During the fourth quarter of 2017, impairment testing indicated that the fair value of the crude oil trucking services reporting unit was less than the carrying value based on the estimated market value of the crude oil trucking services business, and the Partnership recognized impairment of goodwill of $0.9 million related to this reporting unit. Impairment testing indicated there was no impairment of goodwill in 2016 or in 2018. ENVIRONMENTAL MATTERS - Liabilities for loss contingencies, including environmental remediation costs, arising from claims, assessments, litigation, fines, penalties and other sources are charged to expense when it is probable that a liability has been incurred and the amount of the assessment and/or remediation can be reasonably estimated. The Partnership had loss contingencies related to environmental matters of $0.1 million and $0.2 million as of December 31, 2017 and 2018 , respectively. REVENUE RECOGNITION - On January 1, 2018, the Partnership adopted the new accounting standard ASC 606 - Revenue from Contracts with Customers and all related amendments (“new revenue standard”) using the modified retrospective method, and as a result applied the new guidance only to contracts that are not completed at the adoption date. Results for reporting periods beginning on January 1, 2018, are presented under the new revenue standard, while prior period amounts are not adjusted and continue to be reported in accordance with the Partnership’s historic accounting under ASC 605 - Revenue Recognition . See Note 4 for detailed discussion regarding the Partnership’s revenue recognition policies. INCOME AND OTHER TAXES - For federal and most state income tax purposes, the majority of income, gains, losses, deductions and tax credits generated by the Partnership flow through to the unitholders of the Partnership and are subject to income tax at the individual partner level. The Partnership is subject to the Texas state franchise (margin) tax, and the earnings associated with the Partnership’s taxable subsidiary are subject to federal and state income taxes. The Partnership has estimated its liability related to these taxes to be $0.3 million for the year ended 2016 , and $0.2 million for each of the years ended December 31, 2017 and 2018 . This liability is reflected on the Partnership’s consolidated statements of operations as “Provision for income taxes.” See Note 22 for a discussion of certain risks related to the Partnership’s ability to be treated as a partnership for federal income tax purposes. STOCK-BASED COMPENSATION - The Partnership’s general partner adopted the Blueknight Energy Partners G.P. L.L.C. Long-Term Incentive Plan (the “LTIP”). The compensation committee of the Board administers the LTIP. 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 4.1 million common units, subject to adjustment for certain events. Although other types of awards are contemplated under the LTIP, awards issued to date 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. Certain of the phantom unit awards also include distribution equivalent rights (“DERs”). 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. Cash distributions paid on DERs are accounted for as partnership distributions. Recipients of restricted units are entitled to receive cash distributions paid on common units during the vesting period. The Partnership classifies unit award grants as either equity or liability awards. All award grants made under the LTIP from its inception through December 31, 2018 , have been classified as equity awards. Fair value for award grants classified as equity is determined on the grant date of the award and this value is recognized as compensation expense ratably over the requisite service period of unit award grants, which generally is the vesting period. Fair value for equity awards is calculated as the closing price of the Partnership’s common units representing limited partner interests in the Partnership (“common units”) on the grant date and is reduced by the present value of estimated cash distributions to be paid on common units during the vesting period to the extent a unit award does not include DERs. Compensation expense related to unit-based payments is included in operating and general and administrative expenses on the Partnership’s consolidated statements of operations. FAIR VALUE OF FINANCIAL INSTRUMENTS - The Partnership measures all financial instruments, including derivatives embedded in other contracts, at fair value and recognizes them in the consolidated balance sheets as an asset or a liability, depending on its rights and obligations under the applicable contract. The changes in the fair value of financial instruments are recognized currently in earnings in the consolidated statements of operations.

REVENUE REVENUE

REVENUE REVENUE	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer [Text Block]	REVENUE On January 1, 2018, the Partnership adopted the new accounting standard ASC 606 - Revenue from Contracts with Customers and all related amendments (“new revenue standard”) using the modified retrospective method, and as a result applied the new guidance only to contracts that are not completed at the adoption date. Results for reporting periods beginning on January 1, 2018, are presented under the new revenue standard, while prior period amounts are not adjusted and continue to be reported in accordance with the Partnership’s historic accounting under ASC 605 - Revenue Recognition . The majority of the Partnership’s service revenue continues to be recognized as services are performed. Under the new revenue standard, the timing of revenue recognition on variable throughput fees changed, within a single reporting year, compared to the previous recognition. The effect is straight-line recognition of unconstrained estimated annual throughput volumes over each contract year. See further discussion on variable throughput fees below. In addition, as a result of the adoption of the new revenue standard, revenue from leases is required to be presented separately from revenue from customers. As the Partnership applied the modified retrospective method, prior periods have not been reclassified. Upon adoption of the new revenue standard, there was no cumulative adjustment to the balance sheet at January 1, 2018. The adoption of the new revenue standard resulted in a shift in revenue recognition between quarters within a fiscal year; therefore, there is no net effect on the consolidated statements of operations or consolidated balance sheet as of December 31, 2018 , compared to what would have been recorded under ASC 605. The impact of adoption of the new revenue standard is not expected to be material to net income on an ongoing basis because the analysis of contracts under the new revenue standard supports the recognition of revenue as services are performed, which is consistent with the previous revenue recognition model. 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 840 - Leases . The storage, throughput and handling contracts contain both lease revenue and non-lease service revenue. In accordance with ASC 840 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. Asphalt operating lease contracts also contain variable consideration in the form of throughput fees. Utility, fuel and power reimbursements are allocated entirely to the service component of the storage, throughput and handling 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 storage, throughput and handling contracts using the allocation percentages from contract inception as described above. Total throughput fees are estimated at contract inception and updated at the beginning of each reporting period based on historical trends, current year throughput activities at the facilities, and analysis with customers regarding expectations for the current year. This consideration can be constrained when there is a lack of historical data or other uncertainties exist regarding expected throughput volumes. The service component of throughput fees is recognized on a straight-line basis over time as the customer receives and consumes benefits. In accordance with ASC 840, the lease component of variable throughput fees for both types of contracts is recognized in the period when the changes in facts and circumstances on which the variable payment is based occur. Fees related to actual throughput are billed in the month subsequent to the period of movement, which can result in the recognition of un-billed accounts receivable (contract assets) when there is a variance in the straight-line service revenue recognition and actual throughput fees billed. Payment on variable throughput consideration is due within 30 days of billing. Changes in estimated throughput fees affect the total transaction price for the service component of storage, throughput and handling contracts and will be recorded as an adjustment to revenue in the period in which the change in estimate occurs. As of December 31, 2018, all throughput fees are realized. 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 as described above. 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, at which point it is treated as a change in estimate with a prior period catch-up and the remainder to be recognized over the remaining contract term. The lease component is recognized in the period in which the facts and circumstances indicate the variable revenue is assured. In the event the minimum threshold is not met, the Partnership will return the reimbursement to the customer. As of December 31, 2018 , 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) 2019 $ 28,425 2020 27,296 2021 24,154 2022 16,853 2023 11,444 Thereafter 9,142 Total revenue related to future performance obligations $ 117,314 ____________________ (1) Excluded from the table is revenue that is either constrained or related to performance obligations that are wholly unsatisfied as of December 31, 2018 . In addition, as of December 31, 2018 , 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): Year ended December 31, 2019 $ 47,732 2020 42,890 2021 38,873 2022 28,190 2023 19,248 Thereafter 22,342 Total revenue related to minimum future annual lease rentals $ 199,275 The Partnership recognized variable lease consideration of $4.4 million for each of the years ended ended December 31, 2016 and 2017, and $5.1 million for the year ended December 31, 2018, under operating lease agreements. 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): Year ended December 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 $ 18,100 $ 10,966 $ — $ — $ 29,066 Variable throughput revenue 918 962 — — 1,880 Variable reimbursement revenue 7,090 — — — 7,090 Crude oil transportation revenue — — 6,396 14,324 20,720 Crude oil product sales revenue — — 235,428 10 235,438 Related-party revenue: Fixed storage, throughput and other revenue 15,352 — 215 — 15,567 Variable throughput revenue 762 — — — 762 Variable reimbursement revenue 5,572 — 230 — 5,802 Product sales revenue 482 — — — 482 Total revenue from contracts with customers $ 48,276 $ 11,928 $ 242,269 $ 14,334 $ 316,807 Contract Balances The timing of revenue recognition, billings and cash collections result in billed accounts receivable, un-billed accounts receivable (contract assets) and unearned revenue (contract liabilities) on the consolidated balance sheet as noted in the contract discussions above. Accounts receivable and un-billed accounts receivable are both reflected in the line items “Accounts receivable” and “Receivables from related parties” on the consolidated balance sheet. 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 consolidated balance sheet. Billed accounts receivable from contracts with customers were $8.5 million and $34.6 million at December 31, 2017 and 2018 , respectively. There were no un-billed accounts receivable at December 31, 2017 or 2018 . The Partnership records unearned revenues when cash payments are received in advance of performance. Unearned revenue related to contracts with customers was $3.7 million and $5.9 million at December 31, 2017 and 2018 , respectively. The change in the unearned revenue balance for the year ended December 31, 2018 , is driven by $4.0 million in cash payments received in advance of satisfying performance obligations, partially offset by $1.8 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.

ACQUISITIONS ACQUISITIONS

ACQUISITIONS ACQUISITIONS	12 Months Ended
	Dec. 31, 2018
Business Acquisitions [Abstract]
Business Acquisitions Disclosure	ACQUISITIONS On March 7, 2018, the Partnership acquired an asphalt terminalling facility located in Oklahoma from a third party for $22.0 million . On December 1, 2017, the Partnership acquired an asphalt terminalling facility in Bainbridge, Georgia, from Ergon Asphalt & Emulsions, Inc. and Ergon Terminaling, Inc., both subsidiaries of Ergon, for a total purchase price of $10.2 million , consisting of 1,898,380 common units representing limited partner interests in the Partnership. The acquisition was accounted for as a transaction among entities under common control. As a result, the Partnership recorded the acquired assets at Ergon’s historical cost of $6.4 million , net of accumulated depreciation of $7.9 million . The $3.7 million of consideration in excess of Ergon’s historical net book value was recorded as a deemed distribution to the Partnership’s general partner and is reflected as “Consideration paid in excess of historical cost of assets acquired from Ergon” on the Partnership’s consolidated statement of changes in partners’ capital. On October 5, 2016, as part of the Ergon Transaction, the Partnership acquired nine asphalt terminals from Ergon, which accounted for as a transaction among entities under common control. As a result, the Partnership recorded the acquired assets at Ergon’s historical cost of $31.3 million , net of accumulated depreciation of $63.0 million . The $91.3 million of consideration in excess of Ergon’s historical net book value was recorded as a deemed distribution to the Partnership’s general partner and is reflected as “Consideration paid in excess of historical cost of assets acquired from Ergon” on the Partnership’s consolidated statement of changes in partners’ capital. In February 2016, the Partnership acquired two asphalt terminalling facilities located in Virginia and North Carolina from a third party for $19.0 million .

EQUITY METHOD INVESTMENT EQUITY

EQUITY METHOD INVESTMENT EQUITY METHOD INVESTMENT	12 Months Ended
	Dec. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments and Joint Ventures Disclosure [Text Block]	EQUITY METHOD INVESTMENT 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 repay revolving debt under its credit facility. The operating and administrative services agreement to which the Partnership and Advantage Pipeline were parties and under which the Partnership operated the 70-mile, 16-inch Advantage crude oil pipeline, located in the southern Delaware Basin in Texas, was terminated at closing. The Partnership and the Plains/Noble joint venture entered into a short-term transition services agreement under which the Partnership provided certain services through August 1, 2017. Summarized financial information for Advantage Pipeline is set forth in the tables below for the periods indicated in which the Partnership held the investment in Advantage Pipeline (in thousands): Period ended April 3, 2017 Income Statement Operating revenues $ 3,150 Operating expenses $ 465 Net income $ 187

RESTRUCTURING CHARGES RESTRUCTU

RESTRUCTURING CHARGES RESTRUCTURING CHARGES	12 Months Ended
	Dec. 31, 2017
Restructuring Charges [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 plan are summarized as follows: Year ended December 31, 2016 2017 2018 (in thousands) Beginning balance $ 1,565 $ 474 $ 286 Cash payments 1,091 188 286 Ending balance $ 474 $ 286 $ —

PROPERTY, PLANT AND EQUIPMENT

PROPERTY, PLANT AND EQUIPMENT	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
PROPERTY, PLANT AND EQUIPMENT	PROPERTY, PLANT AND EQUIPMENT Estimated Useful Lives (Years) As of December 31, 2017 2018 (dollars in thousands) Land N/A $ 24,776 $ 24,705 Land improvements 10-20 6,787 5,758 Pipelines and facilities 5-30 166,004 116,155 Storage and terminal facilities 10-35 370,056 321,096 Transportation equipment 3-10 3,293 2,798 Office property and equipment and other 3-20 32,011 26,980 Pipeline linefill and tank bottoms N/A 3,233 10,297 Construction-in-progress N/A 6,500 4,026 Property, plant and equipment, gross 612,660 511,815 Accumulated depreciation (316,591 ) (263,554 ) Property, plant and equipment, net $ 296,069 $ 248,261 Plant, property and equipment under operating leases at December 31, 2018 , in which the Partnership is the lessor, had a cost basis of $280.3 million and accumulated depreciation of $170.2 million . Depreciation expense for the years ended December 31, 2016 , 2017 and 2018 was $29.6 million , $29.9 million and $26.9 million , respectively. During the year ended December 31, 2016 , the Partnership recorded fixed asset impairment expense of $25.8 million , primarily due to an impairment recognized on the Knight Warrior pipeline project and the East Texas pipeline system. During the year ended December 31, 2017 , the Partnership recorded fixed asset impairment expense of $1.2 million related to the crude oil trucking reporting unit. During the year ended December 31, 2018 , the Partnership recognized fixed asset impairment expenses of approximately $40.7 million related to a markdown of our pipeline system to estimated fair value, $1.7 million related to the market value of its pipeline linefill assets and $0.4 million related to the value of obsolete trucking stations in Oklahoma and Colorado. In addition, the Partnership recognized a $10.0 million impairment on a push-down basis related to Ergon’s investment in Cimarron Pipeline. See Note 14 for more information. 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 received at closing 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 Partnership used the proceeds received at closing to repay revolving debt under its credit facility. 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. In April 2017, the Partnership sold its East Texas pipeline system. The Partnership received cash proceeds at closing of approximately $4.8 million and recorded a gain of less than $0.1 million . The Partnership used the proceeds received at closing to repay revolving debt under its credit facility. The sale of the East Texas pipeline 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.

INTANGIBLES AND OTHER ASSETS, N

INTANGIBLES AND OTHER ASSETS, NET (Notes)	12 Months Ended
	Dec. 31, 2018
Intangibles and Other Assets [Abstract]
Intangibles And Other Assets, Net [Text Block]	INTANGIBLES AND OTHER ASSETS, NET Intangibles and other assets, net of accumulated amortization, consist of the following: As of December 31, 2017 2018 (in thousands) Customer relationships $ 12,221 $ 19,214 Deferred charges related to pipeline connection agreements 2,716 2,716 Deposits 302 283 Prepaid insurance 353 248 Other prepaid expenses 103 75 Intangibles and other assets, gross 15,695 22,536 Accumulated amortization of intangible assets (2,782 ) (5,096 ) Intangibles and other assets, net $ 12,913 $ 17,440 Amortization expense related to intangibles for the years ended December 31, 2016 , 2017 and 2018 was $1.2 million , $1.3 million and $2.5 million , respectively. The estimated aggregate future amortization expense on amortizable intangible assets currently owned by the Partnership is as follows (in thousands): For year ending: December 31, 2019 $ 2,746 December 31, 2020 2,746 December 31, 2021 2,746 December 31, 2022 2,746 December 31, 2023 1,321 Thereafter 4,529 Total estimated aggregate amortization expense $ 16,834 Customer relationships include $7.6 million and $8.4 million related to the acquisition of asphalt facilities in March 2018 and February 2016, respectively, and $3.2 million related to the acquisition of a pipeline and crude oil marketing business in November 2015. The customer relationships are being amortized over a range of 5 to 20 years. During the year ended December 31, 2017, the Partnership recognized intangible asset impairment charges of $0.2 million on customer relationships related to the producer field services business, primarily operated in the Texas panhandle. During the year ended December 31 2018 , the Partnership recognized intangible asset impairment charges of $0.2 million related to a customer contract asset in crude oil pipeline services business.

DEBT

DEBT	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Debt (Text Block)	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 March 11, 2019 , approximately $253.6 million of revolver borrowings and $1.2 million of letters of credit were outstanding under the credit agreement, leaving the Partnership with available capacity of approximately $145.2 million 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 amended and restated credit agreement may be used for working capital and other general corporate purposes of the Partnership. All references herein to the credit agreement on or after May 11, 2017, refer to the amended and restated credit agreement. 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 from 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 which 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 which 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 letters 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 which 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 5.50 to 1.00 for the fiscal quarter December 31, 2018; 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 is 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 December 31, 2018 , the Partnership’s consolidated total leverage ratio was 5.09 to 1.00 and the consolidated interest coverage ratio was 3.34 to 1.00. The Partnership was in compliance with all covenants of its credit agreement as of December 31, 2018 . 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 $265.6 million in outstanding debt, as of December 31, 2018, 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. In response to the risks described above, management undertook a plan to seek, and ultimately obtained, support from Ergon, the owner of the Partnership’s general partner interest, in the form of a $15.0 million prepayment for certain asphalt lease commitments through September 2019. The Partnership received these funds on March 8, 2019 , and, as of March 12, 2019, paid $14.0 million to reduce outstanding borrowings under the credit agreement, thus providing increased flexibility under the consolidated total leverage ratio covenant. Given this added flexibility, and 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, 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 12 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 50.0% 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 have letters of credit issued under the credit agreement. Upon the execution of the amended and restated credit agreement in May 2017, the Partnership expensed $0.7 million of debt issuance costs related to the prior revolving loan facility, leaving a remaining balance of $0.9 million ascribed to those lenders with commitments under both the prior and the amended and restated credit agreement. Additionally, due to the reduction in available borrowing capacity, the Partnership expensed $0.4 million of debt issuance costs upon the execution of the first amendment to its credit agreement in June 2018. During the years ended December 31, 2016 , 2017 and 2018 , the Partnership capitalized debt issuance costs related to its credit agreement of $1.0 million , $4.2 million and $0.4 million , respectively. The 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 years ended December 31, 2016 and 2017 , was $1.1 million . Interest expense related to debt issuance cost amortization for the year ended December 31, 2018 was $1.0 million . During the years ended December 31, 2016 , 2017 and 2018 , the weighted average interest rate under the Partnership’s credit agreement, excluding the $0.7 million and $0.4 million of debt issuance costs related to the prior credit agreement that were expensed as described above, was 3.95% , 4.43% and 5.49% , respectively, resulting in interest expense of approximately $11.2 million , $13.8 million and $16.8 million , respectively. The Partnership is exposed to market risk for changes in interest rates related to its credit agreement. Interest rate swap agreements are used to manage a portion of the exposure related to changing interest rates by converting floating-rate debt to fixed-rate debt. As of December 31, 2017 and 2018 , the Partnership had interest rate swaps with notional amounts totaling $200.0 million and $100.0 million , respectively, to hedge the variability of its LIBOR-based interest payments. An interest rate swap agreement with a notional amount of $100.0 million expired on June 28, 2018. Interest rate swap agreements with notional amounts totaling $100.0 million matured on January 28, 2019. During the years ended December 31, 2016 , and 2017 , the Partnership recorded swap interest expense of $2.5 million and $1.3 million , respectively. During the year ended December 31, 2018 the Partnership recorded swap interest income of $0.1 million . 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 Values of Derivatives As of December 31, 2017 2018 Interest rate swap assets - current Other current assets $ 68 $ 44 Interest rate swap liabilities - noncurrent Long-term interest rate swap liabilities $ 225 $ — Changes in the fair value of the interest rate swaps are reflected in the consolidated statements of operations as follows (in thousands): Derivatives Not Designated as Hedging Instruments Location of Gain Recognized in Net Income on Derivatives Amount of Gain Recognized in Net Income on Derivatives Year ended December 31, 2016 2017 2018 Interest rate swaps Interest expense, net of capitalized interest $ 1,156 $ 1,790 $ 201

NET INCOME PER LIMITED PARTNER

NET INCOME PER LIMITED PARTNER UNIT	12 Months Ended
	Dec. 31, 2018
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): Year ended December 31, 2016 2017 2018 Net income (loss) $ (4,840 ) $ 20,045 $ (42,047 ) General partner interest in net income (loss) 433 944 (512 ) Preferred interest in net income 25,824 25,115 25,115 Net loss available to limited partners $ (31,097 ) $ (6,014 ) $ (66,650 ) Basic and diluted weighted average number of units: Common units 35,093 38,342 40,348 Restricted and phantom units 803 862 1,011 Total units 35,896 39,204 41,359 Basic and diluted net loss per common unit $ (0.87 ) $ (0.15 ) $ (1.61 )

PARTNERS' CAPITAL AND DISTRIBUT

PARTNERS' CAPITAL AND DISTRIBUTIONS	12 Months Ended
	Dec. 31, 2018
Partners' Capital Account, Distributions [Abstract]
PARTNERS' CAPITAL AND DISTRIBUTIONS	PARTNERS’ CAPITAL AND DISTRIBUTIONS On December 1, 2017, the Partnership issued 1,898,380 common units to Ergon in a private placement for $10.2 million in exchange for an asphalt facility in Bainbridge, Georgia. See additional detail in Note 5 . On October 5, 2016, the Partnership completed the following transactions: • issued 847,457 common units to Ergon in a private placement for $5.0 million ; • repurchased 6,667,695 Preferred Units from each Vitol and Charlesbank for an aggregate purchase price of approximately $95.3 million , leaving both Vitol and Charlesbank with 2,488,789 Preferred Units upon completion of these transactions; and • issued 18,312,968 Preferred Units to Ergon for $144.7 million , as well as 97,654 general partner units to Ergon for $0.7 million . On July 26, 2016, the Partnership issued and sold 3,795,000 common units for a public offering price of $5.90 per unit, resulting in proceeds of approximately $20.9 million , net of underwriters’ discount and offering expenses of $1.5 million . In accordance with the terms of its partnership agreement, each quarter the Partnership distributes all of its available cash (as defined in the partnership agreement) to its unitholders. Generally, distributions are allocated as follows: • first, 98.4% to the preferred unitholders and 1.6% to its general partner until the Partnership distributes for each Preferred Unit an amount equal to the Preferred Units quarterly distribution amount discussed below; • second, 98.4% to the preferred unitholders and 1.6% to its general partner until the Partnership distributes for each Preferred Unit an amount equal to any Preferred Units cumulative distribution arrearage; and • thereafter, 98.4% to the common unitholders and 1.6% to its general partner until the common unitholders receive the minimum quarterly distribution of $0.11 per unit. The Preferred Units are convertible at the holders’ option into common units. Holders of the Preferred Units are entitled to quarterly distributions of $0.17875 per unit per quarter. If the Partnership fails to pay in full any distribution on the Preferred Units, the amount of such unpaid distribution will accrue and accumulate from the last day of the quarter for which such distribution is due until paid in full. The general partner receives incentive distribution rights. Incentive distribution rights represent the right to receive an increasing percentage ( 13.0% , 23.0% and 48.0% ) of quarterly distributions of available cash from operating surplus after the minimum quarterly distribution and the target distribution levels have been achieved. The general partner currently holds the incentive distribution rights, but may transfer these rights separately from its general partner interest, subject to restrictions in the partnership agreement. If for any quarter: • the Partnership has distributed available cash from operating surplus to the holders of our Preferred Units in an amount equal to the Preferred Units quarterly distribution amount; • the Partnership has distributed available cash from operating surplus to the holders of our Preferred Units in an amount necessary to eliminate any cumulative arrearages in the payment of the Preferred Units quarterly distribution amount; and • the Partnership has distributed available cash from operating surplus to the common unitholders and Class B unitholders in an amount equal to the minimum quarterly distribution; then the partnership agreement requires that the Partnership distribute any additional available cash from operating surplus for that quarter among the unitholders and the general partner in the following manner: • first, 98.4% to all unitholders holding common units or Class B units, pro rata, and 1.6% to the general partner, until each unitholder receives a total of $0.1265 per unit for that quarter (the “first target distribution”); • second, 85.4% to all unitholders holding common units or Class B units, pro rata, and 14.6% to the general partner, until each unitholder receives a total of $0.1375 per unit for that quarter (the “second target distribution”); • third, 75.4% to all unitholders holding common units or Class B units, pro rata, and 24.6% to the general partner, until each unitholder receives a total of $0.1825 per unit for that quarter (the “third target distribution”); and • thereafter, 50.4% to all unitholders holding common units or Class B units, pro rata, and 49.6% to the general partner. Distributions are also paid to the holders of restricted units and phantom units as disclosed in Note 15 . The Partnership paid the following distributions on the Preferred Units during the years ended December 31, 2016 , 2017 and 2018 (in thousands): Year Paid Periods Covered Total Paid to Preferred Unitholders Paid to General Partner 2016 Quarters ending December 31, 2015, March 31, 2016, June 30, 2016 and September 30, 2016 $ 22,837 $ 22,449 $ 388 2017 Quarters ending December 31, 2016, March 31, 2017, June 30, 2017 and September 30, 2017 $ 25,534 $ 25,115 $ 420 2018 Quarters ending December 31, 2017, March 31, 2018, June 30, 2018 and September 30, 2018 $ 25,523 $ 25,115 $ 408 In addition, on January 25, 2019 , the Board approved a cash distribution of $0.17875 per outstanding Preferred Unit for the quarter ending December 31, 2018 . The Partnership paid this distribution on the Preferred Units on February 14, 2019 , to unitholders of record as of February 4, 2019 . The total distribution was approximately $6.4 million , with approximately $6.3 million and $0.1 million paid to the Partnership’s preferred unitholders and general partner, respectively. The Partnership paid the following distributions on the common units during the years ended December 31, 2016 , 2017 and 2018 (in thousands): Year Paid Periods Covered Total Paid to Common Unitholders Paid to General Partner Paid to Phantom and Restricted Unitholders Under the LTIP 2016 Quarters ending December 31, 2015, March 31, 2016, June 30, 2016 and September 30, 2016 $ 21,900 $ 20,509 $ 933 $ 458 2017 Quarters ending December 31, 2016, March 31, 2017, June 30, 2017 and September 30, 2017 $ 23,629 $ 22,147 $ 994 $ 488 2018 Quarters ending December 31, 2017, March 31, 2018, June 30, 2018 and September 30, 2018 $ 19,213 $ 18,154 $ 626 $ 433 In addition, on January 25, 2019 , the Board approved a cash distribution of $0.08 per outstanding common unit for the quarter ending December 31, 2018 . The distribution was paid on February 14, 2019 , to unitholders of record as of February 4, 2019 . The total distribution was approximately $3.4 million , with approximately $3.3 million and $0.1 million paid to the Partnership’s common unitholders and general partner, respectively, and $0.1 million paid to holders of phantom and restricted units pursuant to awards granted under the LTIP.

MAJOR CUSTOMERS AND CONCENTRATI

MAJOR CUSTOMERS AND CONCENTRATION OF CREDIT RISK (Notes)	12 Months Ended
	Dec. 31, 2018
Risks and Uncertainties [Abstract]
Concentration Risk Disclosure [Text Block]	MAJOR CUSTOMERS AND CONCENTRATION OF CREDIT RISK Significant customers are defined as those who represent 10% or more of our total consolidated revenues during the year. For the year ended December 31, 2016, Ergon accounted for approximately 13% of the Partnership’s total revenues, all of which were earned in asphalt terminalling services. One third-party customer accounted for approximately 13% of the Partnership’s total revenues, which were earned in all of the Partnership’s operating segments. For the year ended December 31, 2017, Ergon accounted for approximately 31% of the Partnership’s total revenues, all of which were earned in asphalt terminalling services. One third-party customer accounted for approximately 12% of the Partnership’s total revenues, which were earned in all of the Partnership’s operating segments. For the year ended December 31, 2018, Ergon accounted for approximately 13% of the Partnership’s total revenues, which were earned in asphalt terminalling services and crude oil pipeline services. One third-party customer accounted for approximately 10% of the Partnership’s total revenues, which were earned in all of the Partnership’s operating segments. In addition, two other third-party customers each accounted for 15% of the Partnership’s total revenues, which were all earned in the Partnership’s crude oil pipeline services.

RELATED PARTY TRANSACTIONS

RELATED PARTY TRANSACTIONS	12 Months Ended
	Dec. 31, 2018
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	RELATED-PARTY TRANSACTIONS On October 5, 2016, Ergon purchased 100% of the Partnership’s general partner from Vitol and Charlesbank, resulting in Ergon being classified as a related party and Vitol and Charlesbank no longer being classified as related parties as of October 5, 2016. The Partnership leases facilities to Ergon and provides liquid asphalt terminalling services to Ergon. For the year ended December 31, 2016 , the Partnership recognized revenues of $22.2 million for services provided to Ergon, of which $11.0 million is classified as related-party revenues. For the years ended December 31, 2017 and 2018 , the Partnership recognized revenues of $56.4 million and $48.5 million , respectively, for services provided to Ergon, all of which is classified as related-party revenue. See additional discussion below regarding material asphalt operating lease contracts and storage, throughput and handling contracts. As of December 31, 2017 and 2018 , the Partnership had receivables from Ergon of $3.1 million and $1.0 million , respectively. On March 8, 2019 , Ergon made a $15.0 million prepayment of fees representing six months’ of future services under the Ergon Lessee Operated Facility Lease Agreements and Ergon Fontana and Las Vegas Storage Throughput and Handling Agreement. The Partnership used the proceeds of this prepayment to prepay revolving debt under its credit agreement. 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 Pipeline, LLC (“Cimarron Express”), subject to certain terms and conditions. The Agreement was filed as Exhibit 10.1 to the Partnership’s Current Report on Form 8-K, filed May 14, 2018. Cimarron Express is 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 has 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 BKEP 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, Ergon and the Partnership 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 BKEP or its designee. There is not a separate amount of consideration for the Put or the Call exchanged between the parties. Therefore, based on applicable GAAP, no value was assigned to the combined instrument on the Partnership's balance sheet upon the execution of the put/call instrument. As of December 31, 2018, neither Ergon nor the Partnership has exercised their options under the Agreement. In December of 2018, the Partnership and Ergon became aware of circumstances adversely impacting the projected economic performance of Cimarron Express. The Partnership and Ergon have worked together to evaluate available information about Cimarron Express, and have determined that Cimarron Express is likely no longer economically viable. As of December 31, 2018, Cimarron Express has 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, and has cash on hand of approximately $1.9 million . 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 $17.6 million . 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 has 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. 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 year ended December 31, 2018 , the Partnership made purchases of crude oil under this agreement totaling $ 108.8 million . As of December 31, 2018 , the Partnership had payables to Ergon related to this agreement of $ 10.2 million related to the December crude oil settlement cycle, and this balance was paid in full on January 22, 2019 . The Partnership also provided operating and administrative services to Advantage Pipeline. On April 3, 2017, the Partnership sold its investment in Advantage Pipeline and the operating and administrative services agreement was terminated. For the years ended December 31, 2016 and 2017 , the Partnership recognized revenues of $1.3 million and $0.3 million , respectively, for services provided to Advantage Pipeline. The Partnership provides crude oil gathering, transportation and terminalling services to Vitol. For the year ended December 31, 2016 , the Partnership recognized related-party revenues of $17.9 million for services provided to Vitol. Ergon 2017 Lubbock and Saginaw Storage and Handling Agreement In September 2016, the Partnership and Ergon entered into a storage, throughput and handling agreement pursuant to which the Partnership provides Ergon storage and terminalling services at the Lubbock and Saginaw asphalt facilities. The term of this agreement commenced on January 1, 2017, and was to continue for six years. In July 2018, the Partnership sold the Lubbock and Saginaw facilities to Ergon and this agreement was terminated. The Board’s conflicts committee reviewed and approved this agreement in accordance with the Partnership’s procedures for approval of related-party transactions and the provisions of the partnership agreement. During the years ended December 31, 2017 and 2018 , the Partnership generated revenues under this agreement of $12.9 million and $6.7 million , respectively, all of which is classified as related-party revenue. Ergon 2016 Storage and Handling Agreement In October 2016, the Partnership and Ergon entered into a storage, throughput and handling agreement (the “Ergon 2016 Storage and Handling Agreement”) pursuant to which the Partnership provides Ergon storage and terminalling services at nine asphalt facilities. The term of the Ergon 2016 Storage, Throughput and Handling Agreement commenced on October 5, 2016, and continues for seven years. The Board’s conflicts committee reviewed and approved this agreement in accordance with the Partnership’s procedures for approval of related-party transactions and the provisions of the partnership agreement. During the years ended December 31, 2016 , 2017 and 2018 , the Partnership generated revenue under this agreement of $6.2 million , $26.4 million and $24.8 million , respectively, all of which is classified as related-party revenue. Ergon Fontana and Las Vegas Storage Throughput and Handling Agreement In October 2016, the Partnership and Ergon entered into a storage, throughput and handling agreement (the “Ergon Fontana and Las Vegas Storage Throughput and Handling Agreement”) pursuant to which the Partnership provides Ergon storage and terminalling services at two asphalt facilities. The original Ergon Fontana and Las Vegas Master Facilities Lease Agreement commenced on May 18, 2009, and was a part of Ergon Master Facilities Lease and Sublease Agreement. See Ergon Master Facilities Lease and Sublease Agreement for additional detail regarding prior terms and conditions. The term of the Ergon Fontana and Las Vegas Storage Throughput and Handling Agreement commenced on October 5, 2016, and expired on December 31, 2018. A new agreement was executed in March 2019 with an effective date of January 1, 2019. This agreement has an initial term of five years. The Board’s conflicts committee reviewed and approved these agreements in accordance with the Partnership’s procedures for approval of related-party transactions and the provisions of the partnership agreement. During the years ended December 31, 2016 , 2017 and 2018 , the Partnership generated revenues under this agreement of $1.5 million , $6.2 million and $6.6 million , respectively, all of which is classified as related-party revenue. Ergon Master Facilities Lease and Sublease Agreement In May 2009, the Partnership and Ergon entered into a facilities lease and sublease agreement (the “Ergon Master Facilities Lease and Sublease Agreement”) pursuant to which the Partnership leases Ergon certain facilities. The original term of the Ergon Master Facilities Lease and Sublease Agreement commenced on May 18, 2009, for two years, until December 31, 2011. The Ergon Master Facilities Lease and Sublease Agreement has been amended and extended several times and encompassed eight facilities through June 2018. In July 2018, the Partnership sold one of the facilities covered by this agreement and it was amended to remove that facility. This agreement expired on December 31, 2018, and a new agreement, the Lessee Operated Facility Lease Agreement, was executed in March 2019. The new agreement encompasses 12 facilities, which includes facilities previously accounted for under this agreement and the Ergon Master Facilities Sublease and Sublicense Agreement. The new agreement has an effective date of January 1, 2019, and an initial term of five years. The Board’s conflicts committee reviewed and approved these agreements in accordance with the Partnership’s procedures for approval of related-party transactions and the provisions of the partnership agreement. During the year ended December 31, 2016 , the Partnership generated revenues under this agreement of $9.2 million , of which $1.8 million is classified as related-party revenue. During the years ended December 31, 2017 and 2018, the Partnership generated revenues under this agreement of $5.2 million and $5.3 million , respectively, all of which is classified as related-party revenue. Ergon Master Facilities Sublease and Sublicense Agreement In May 2009, the Partnership and Ergon entered into multiple sublease and sublicense agreements covering five facilities. The original terms of these agreements commenced on May 18, 2009, for two years, until December 31, 2011. In November 2010, these multiple leases were consolidated under one master sublease and sublicense agreement. This agreement was amended in June 2015 and expired on December 31, 2018. This agreement expired on December 31, 2018, and a new agreement, the Lessee Operated Facility Lease Agreement, was executed in March 2019. The new agreement combined the facilities under this agreement and the Ergon Master Facilities Lease and Sublease Agreement. The new agreement has an effective date of January 1, 2019, and an initial term of five years. During the year ended December 31, 2016 , the Partnership generated revenues under this agreement of $3.6 million , of which $1.0 million is classified as related-party revenue. During the years ended December 31, 2017 and 2018, the Partnership generated revenues under this agreement of $3.7 million and $2.8 million , all of which is classified as related-party revenue. Vitol Storage Agreements In recent years, a significant portion of the Partnership’s crude oil storage capacity has been dedicated to Vitol under multiple agreements. During the year ended December 31, 2016 , when Vitol was a related party, 2.2 million barrels of storage capacity were dedicated to Vitol under these storage agreements. Service revenues under these agreements are based on the barrels of storage capacity dedicated to Vitol under the applicable agreement at rates that, the Partnership believes, are fair and reasonable to the Partnership and its unitholders and are comparable with the rates the Partnership charges third parties. The Board’s conflicts committee reviewed and approved these agreements in accordance with the Partnership’s procedures for approval of related-party transactions and the provisions of the partnership agreement. For the year ended December 31, 2016, the Partnership generated revenues under these agreements of approximately $9.6 million , of which $7.5 million is classified as related-party revenue.

LONG-TERM INCENTIVE PLAN

LONG-TERM INCENTIVE PLAN	12 Months Ended
	Dec. 31, 2018
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 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 4.1 million common units, subject to adjustment 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. Certain of the phantom unit awards also include 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 that 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 grants made to the directors under the LTIP subject to vesting requirements: Grant Date Number of Units Weighted Average Grant Date Fair Value 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 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 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 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 Grant Date Total Fair Value (in thousands) March 2016 416,131 $ 4.77 $ 1,985 October 2016 9,960 $ 5.85 $ 58 March 2017 323,339 $ 7.15 $ 2,312 March 2018 396,536 $ 4.77 $ 1,891 The unrecognized estimated compensation cost relating to outstanding phantom units at December 31, 2018 , was $1.9 million , which will be recognized over the remaining vesting period. On January 1, 2019, 302,786 units of the March 2016 grant vested. The Partnership’s equity-based incentive compensation expense for the years ended December 31, 2016 , 2017 and 2018 was $2.5 million , $2.2 million and $2.2 million , respectively. Activity pertaining to phantom common units and restricted common unit awards granted under the LTIP is as follows: Number of Units Weighted Average Grant Date Fair Value Nonvested, December 31, 2017 923,551 $ 6.29 Granted 503,295 4.45 Vested 311,927 6.71 Forfeited 116,700 5.44 Nonvested, December 31, 2018 998,219 $ 5.88

EMPLOYEE BENEFIT PLAN

EMPLOYEE BENEFIT PLAN	12 Months Ended
	Dec. 31, 2018
Retirement Benefits [Abstract]
EMPLOYEE BENEFIT PLAN	EMPLOYEE BENEFIT PLAN 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 $1.2 million for each of the years ended December 31, 2016 , 2017 and 2018 , 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 the Board for approval. The Partnership recognized expense of $0.8 million for each of the years ended December 31, 2016 and 2017 , respectively, and $0.2 million for the year ended December 31, 2018 , 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 expense of $0.1 million for each of the years ended December 31, 2016 , 2017 and 2018 , in connection with the Unit Purchase Plan.

PROFITS INTEREST OF BLUEKNIGHT

PROFITS INTEREST OF BLUEKNIGHT GP HOLDING, LLC (Notes)	12 Months Ended
	Dec. 31, 2018
PROFITS INTEREST OF BLUEKNIGHT GP HOLDING, LLC [Abstract]
Profits Interest Of Parent Company [Text Block]	PROFITS INTEREST OF BLUEKNIGHT GP HOLDING, LLC In October 2012, the owners of Blueknight GP Holding, LLC (“HoldCo”), the owner of the general partner, admitted Mr. Hurley as a member of HoldCo. In connection with his admission as a member of HoldCo, Mr. Hurley was issued a non-voting economic interest in HoldCo (the “Profits Interest”). Upon the Ergon Change of Control, Vitol and Charlesbank, the previous owners of HoldCo, repurchased and canceled the Profits Interest. Although the entire economic burden of the Profits Interest, which was equity classified, was borne solely by HoldCo and did not impact the Partnership’s cash or units outstanding, the intent of the Profits Interest was to provide a performance incentive and encourage retention of Mr. Hurley. Therefore, the Partnership recognized the grant date fair value of the Profits Interest as compensation expense over the service period and the repurchase of the Profits Interest in the period paid. The expense is also reflected as a capital contribution and, therefore, results in a corresponding credit to partners’ capital in the Partnership’s consolidated financial statements. The Partnership recognized expense of $0.9 million in relation to the Profits Interest during the year ended December 31, 2016 .

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
COMMITMENT AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES The Partnership leases certain real property and equipment under various operating leases. It also incurs costs associated with leased land, rights-of-way, permits and regulatory fees, the contracts for which generally extend beyond one year but can be cancelled at any time should they no longer be required for operations. Future non-cancellable commitments related to these items at December 31, 2018 , are summarized below (in thousands): For year ending: Operating Leases December 31, 2019 $ 2,862 December 31, 2020 1,904 December 31, 2021 1,242 December 31, 2022 640 December 31, 2023 548 Thereafter 1,259 Total future minimum lease payments $ 8,455 Rental expense was $6.5 million , $6.2 million and $5.0 million for the years ended December 31, 2016 , 2017 and 2018 , respectively. 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 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 services will cease, and the Partnership does not believe that such demand will cease in 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 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.

ENVIRONMENTAL REMEDIATION (Note

ENVIRONMENTAL REMEDIATION (Notes)	12 Months Ended
	Dec. 31, 2018
Accrual for Environmental Loss Contingencies Disclosure [Abstract]
Environmental Loss Contingency Disclosure [Text Block]	ENVIRONMENTAL REMEDIATION The Partnership maintains insurance of various types with varying levels of coverage that it considers adequate under the circumstances to cover its operations and properties. The insurance policies are subject to deductibles and retention levels that the Partnership considers reasonable and not excessive. Consistent with insurance coverage generally available in the industry, in certain circumstances the Partnership’s insurance policies provide limited coverage for losses or liabilities relating to gradual pollution, with broader coverage for sudden and accidental occurrences. Although the Partnership maintains a program designed to prevent and, as applicable, to detect and address such releases promptly, damages and liabilities incurred due to environmental releases from its assets may substantially affect its business. At December 31, 2017 and 2018 , the Partnership was aware of existing conditions that may cause it to incur expenditures in the future for the remediation of existing environmental matters. The Partnership had loss contingencies of $0.1 million and $0.2 million as of December 31, 2017 and 2018 , respectively. Changes in the Partnership’s estimates and assumptions may occur as a result of the passage of time and the occurrence of future events.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	12 Months Ended
	Dec. 31, 2018
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 these assets and liabilities 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. 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, 2017 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 $ 68 $ — $ 68 $ — Total swap assets $ 68 $ — $ 68 $ — Liabilities: Interest rate swap liabilities $ 225 $ — $ 225 $ — Total swap liabilities $ 225 $ — $ 225 $ — 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 $ — 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 December 31, 2018 , the carrying values on the 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 December 31, 2018 , 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.

OPERATING SEGMENTS

OPERATING SEGMENTS	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
OPERATING SEGMENTS	OPERATING SEGMENTS The Partnership’s operations consist of four operating 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 liquid asphalt cement and residual fuel oil terminalling services at its 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. The Partnership previously owned and operated the East Texas pipeline system, which is located in Texas. On April 18, 2017, the Partnership sold the East Texas pipeline system. See Note 8 for additional information. Crude oil marketing revenues consist of sales proceeds recognized for the sale of crude oil to third-party customers. Revenue for the sale of crude oil is recognized when title to the crude oil transfers to the customer and is based on contractual prices for the sale of crude oil. 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 terminalling facilities located along pipeline gathering and transportation systems. On April 24, 2018, the Partnership sold the producer field services business. As a result of the sale of the producer field services business, the Partnership changed the name of this operating segment to crude oil trucking services during the second quarter of 2018. See Note 8 for additional information. The Partnership’s management evaluates performance based upon segment operating margin, which includes revenues from related parties and external customers and operating expense excluding depreciation and amortization. The non-GAAP measure of operating margin (in the aggregate and by segment) is presented in the following table. The Partnership computes the components of operating margin 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 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 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): Year ended December 31, 2016 2017 2018 Asphalt Terminalling Services Service revenue: Third-party revenue $ 75,655 $ 57,486 $ 26,108 Related-party revenue 11,762 56,378 21,686 Lease revenue: Third-party revenue — — 41,319 Related-party revenue — — 25,961 Product sales revenue: Related-party revenue — — 482 Total revenue for reportable segments 87,417 113,864 115,556 Operating expense, excluding depreciation and amortization 30,648 49,241 49,229 Operating margin, excluding depreciation and amortization 56,769 64,623 66,327 Additions to long-lived assets 148,622 22,046 30,068 Total assets (end of period) $ 141,280 $ 146,966 $ 138,245 Crude Oil Terminalling Services Service revenue: Third-party revenue $ 16,387 $ 22,177 $ 11,928 Related-party revenue 7,858 — — Intersegment revenue — — 704 Lease revenue: Third-party revenue — — 45 Total revenue for reportable segments 24,245 22,177 12,677 Operating expense, excluding depreciation and amortization 4,197 4,200 3,899 Operating margin, excluding depreciation and amortization 20,048 17,977 8,778 Additions to long-lived assets 2,126 2,194 3,394 Total assets (end of period) $ 71,689 $ 69,149 $ 68,480 Year ended December 31, 2016 2017 2018 Crude Oil Pipeline Services Service revenue: Third-party revenue $ 8,662 $ 9,580 $ 6,396 Related-party revenue 5,433 310 445 Lease revenue: Third-party revenue — — 484 Product sales revenue: Third-party revenue 20,968 11,094 235,428 Total revenue for reportable segments 35,063 20,984 242,753 Operating expense, excluding depreciation and amortization 15,270 13,310 11,828 Intersegment operating expense 890 417 5,284 Third-party cost of product sales 14,130 8,807 126,776 Related-party cost of product sales — — 102,469 Intersegment cost of product sales 426 150 — Operating margin, excluding depreciation and amortization 4,347 (1,700 ) (3,604 ) Additions to long-lived assets 8,250 2,934 19,654 Total assets (end of period) $ 150,043 $ 117,749 $ 112,429 Crude Oil Trucking Services Service revenue: Third-party revenue $ 25,511 $ 24,529 $ 14,324 Related-party revenue 5,158 — — Intersegment revenue 890 417 4,580 Lease revenue: Third-party revenue — — 219 Product sales revenue: Third-party revenue — 385 10 Intersegment revenue 426 150 — Total revenue for reportable segments 31,985 25,481 19,133 Operating expense, excluding depreciation and amortization 30,156 25,915 19,575 Operating margin, excluding depreciation and amortization 1,829 (434 ) (442 ) Additions to long-lived assets 2,558 1,701 3,243 Total assets (end of period) $ 12,651 $ 7,005 $ 4,150 Total operating margin, excluding depreciation and amortization (1) $ 82,993 $ 80,466 $ 71,059 Total segment revenues 178,710 182,506 390,119 Elimination of intersegment revenues (1,316 ) (567 ) (5,284 ) Consolidated revenues 177,394 181,939 384,835 ____________________ (1) The following table reconciles segment operating margin, excluding depreciation and amortization to income (loss) before income taxes (in thousands): Year ended December 31, 2016 2017 2018 Operating margin (excluding depreciation and amortization) $ 82,993 $ 80,466 $ 71,059 Depreciation and amortization (30,820 ) (31,139 ) (29,359 ) General and administrative expenses (20,029 ) (17,112 ) (15,995 ) Asset impairment expense (25,761 ) (2,400 ) (53,068 ) Gain (loss) on sale of assets 108 (975 ) 149 Equity earnings in unconsolidated affiliate 1,483 61 — Gain on sale of unconsolidated affiliate — 5,337 2,225 Interest expense (12,554 ) (14,027 ) (16,860 ) Income (loss) before income taxes $ (4,580 ) $ 20,211 $ (41,849 )

INCOME TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES The anticipated after-tax economic benefit of an investment in the Partnership’s common units depends largely on the Partnership being treated as a partnership for federal income tax purposes. If less than 90% of the gross income of a publicly traded partnership, such as the Partnership, for any taxable year is “qualifying income” from sources such as the transportation, marketing (other than to end users) or processing of crude oil, natural gas or products thereof, interest, dividends or similar sources, that partnership will be taxable as a corporation under Section 7704 of the Internal Revenue Code for federal income tax purposes for that taxable year and all subsequent years. If the Partnership were treated as a corporation for federal income tax purposes, then it would pay federal income tax on its income at the applicable corporate tax rate and would likely pay state income tax at varying rates. Distributions would generally be taxed again to unitholders as corporate distributions and none of the Partnership’s income, gains, losses, deductions or credits would flow through to its unitholders. Because a tax would be imposed upon the Partnership as an entity, cash available for distribution to its unitholders would be substantially reduced. Treatment of the Partnership as a corporation would result in a material reduction in the anticipated cash flow and after-tax return to unitholders and thus would likely result in a substantial reduction in the value of the Partnership’s common units. The Partnership has entered into storage contracts and leases with third-party customers with respect to substantially all of its asphalt facilities. At the time of entering into such agreements, it was unclear under current tax law as to whether the rental income from the leases, and the fees attributable to certain of the processing services the Partnership provides under certain of the storage contracts, constitute “qualifying income.” In the second quarter of 2009, the Partnership submitted a request for a ruling from the IRS that rental income from the leases constitutes “qualifying income.” In October 2009, the Partnership received a favorable ruling from the IRS. As part of this ruling, however, the Partnership agreed to transfer, and has transferred, certain of its asphalt processing assets and related fee income to a subsidiary taxed as a corporation. This transfer occurred in the first quarter of 2010. Such subsidiary is required to pay federal income tax on its income at the applicable corporate tax rate and will likely pay state (and possibly local) income tax at varying rates. Distributions from this subsidiary will generally be taxed again to unitholders as corporate distributions and none of the income, gains, losses, deductions or credits of this subsidiary will flow through to the Partnership’s unitholders. On December 22, 2017, the Tax Cut and Jobs Act (“TCJA”) was enacted into law. Among its many tax reform provisions, TCJA reduced the federal corporate income tax rate from 35% to 21% for the tax year beginning after December 31, 2017. As a result, the Partnership revalued the deferred tax effects of the temporary differences between its taxable subsidiary’s tax basis of assets and liabilities and the financial reporting amounts at December 31, 2017 , which resulted in a reduction of the taxable subsidiary’s gross deferred tax asset of $0.3 million . The net deferred tax effect of the taxable entity’s temporary differences at December 31, 2018 , are presented below (in thousands): Deferred Tax Asset Difference in bases of property, plant and equipment $ 273 Deferred tax asset 273 Less: valuation allowance (273 ) Net deferred tax asset $ — The Partnership has considered the taxable income projections in future years, whether the carryforward period is so brief that it would limit realization of tax benefits, 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 full valuation allowance against its deferred tax asset as of December 31, 2018 .

RECENTLY ISSUED ACCOUNTING STAN

RECENTLY ISSUED ACCOUNTING STANDARDS	12 Months Ended
	Dec. 31, 2018
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
RECENTLY ISSUED ACCOUNTING STANDARDS	RECENTLY ISSUED ACCOUNTING STANDARDS In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers.” The amendments in this update create Topic 606, Revenue from Contracts with Customers, and supersede the revenue recognition requirements in Topic 605, Revenue Recognition, including most industry-specific revenue recognition guidance throughout the Industry Topics of the Codification. In summary, the core principle of Topic 606 is that an entity recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. Throughout 2015, 2016 and 2017, the FASB issued a series of subsequent updates to the revenue recognition guidance in Topic 606. The amendments in ASU 2014-09 and the related updates are effective for public entities for annual reporting periods beginning after December 15, 2017, and for interim periods within that reporting period. The Partnership adopted this standard as of January 1, 2018, using the modified retrospective approach, which allows for applying the new standard to (i) all new contracts entered into after January 1, 2018, and (ii) all existing contracts for which all (or substantially all) of the revenue has not been recognized under legacy revenue guidance as of January 1, 2018, through a cumulative adjustment to equity. Revenues presented in the comparative consolidated financial statements for periods prior to January 1, 2018, were not revised. See Note 4 for disclosures related to the adoption of this standard and the impact on the Partnership’s financial position, results of operations and cash flows. In January 2016, the FASB issued ASU 2016-01, “Financial Instruments - Overall (Subtopic 825-10).” This update is intended to enhance the reporting model for financial instruments in order to provide users of financial statements with more decision-useful information. The amendments in the update address certain aspects of recognition, measurement, presentation and disclosure of financial instruments. This update is effective for financial statements issued for annual periods beginning after December 15, 2017, and interim periods within those fiscal years. The Partnership adopted this update as of January 1, 2018, and there was no impact on the Partnership’s financial position, results of operations or cash flows. In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842).” This update introduces a new lease model that requires the recognition of lease assets and lease liabilities on the balance sheet and the disclosure of key information about leasing arrangements. Throughout 2017 and 2018, the FASB issued a series of subsequent updates to the guidance in Topic 842. This update, as well as related updates, is effective for financial statements issued for annual periods beginning after December 15, 2018, and interim periods within those fiscal years. The Partnership adopted this standard as of January 1, 2019, using the modified retrospective approach, and elected to apply the provisions at the beginning of the period of adoption. In addition, the Partnership elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allowed the Partnership to carry forward the historical lease classification. The Partnership will have no cumulative adjustment to equity on the effective date. The overall impact to the Partnership’s results is not expected to be material; however, the Partnership expects a change in classification from operating lease to financing lease for heavy-duty tractor and trailer leases entered into after the period of adoption under the new guidance. The opening balance sheet impact will be to record operating lease right of use assets of $11.7 million and operating leaselease liabilities of $11.9 million on January 1, 2019. Our finance lease assets and liabilities of $0.6 million did not change as a result of adopting this standard. In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments.” This update addresses the following eight specific cash flow issues: debt prepayment or debt extinguishment costs; settlement of zero-coupon debt instruments or other debt instruments with coupon interest rates that are insignificant in relation to the effective interest rate of the borrowing; contingent consideration payments made after a business combination; proceeds from the settlement of insurance claims; proceeds from the settlement of corporate-owned life insurance policies (including bank-owned life insurance policies); distributions received from equity method investees; beneficial interests in securitization transactions; and separately identifiable cash flows and application of the predominance principle. This update is effective for financial statements issued for annual periods beginning after December 15, 2017, and interim periods within those fiscal years. The Partnership adopted this update as of January 1, 2018, and there was no impact on the Partnership’s financial position, results of operations or cash flows. In October 2016, the FASB issued ASU 2016-16, “Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other than Inventory.” This update is intended to improve the accounting for the income tax consequences of intra-entity transfers of assets other than inventory. The amendments in the update eliminate the prohibition of recognizing current and deferred income taxes for an intra-entity asset transfer other than inventory until the asset has been sold to an outside party. This update is effective for financial statements issued for annual periods beginning after December 15, 2017, and interim periods within those fiscal years. The Partnership adopted this update as of January 1, 2018, and there was no impact on the Partnership’s financial position, results of operations or cash flows. In November 2016, the FASB issued ASU 2016-18, “Statement of Cash Flows (Topic 230): Restricted Cash (a Consensus of the FASB Emerging Issues Task Force).” This update requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents and amounts generally described as restricted cash or restricted cash equivalents . This update is effective for financial statements issued for annual periods beginning after December 15, 2017, and interim periods within those fiscal years. The Partnership adopted this update as of January 1, 2018, and there was no impact on the Partnership’s financial position, results of operations or cash flows. In January 2017, the FASB issued ASU 2017-01, “Business Combinations (Topic 805): Clarifying the Definition of a Business.” This update clarifies the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. This update is effective for financial statements issued for annual periods beginning after December 15, 2017, and interim periods within those fiscal years. The Partnership adopted this update as of January 1, 2018, and there was no impact on the Partnership’s financial position, results of operations or cash flows. In February 2017, the FASB issued ASU 2017-05, “Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20).” This update clarifies the scope of Subtopic 610-20 and adds guidance for partial sales of nonfinancial assets. Subtopic 610-20, which was issued in May 2014 as a part of ASU 2014-09, “Revenue from Contracts with Customers (Topic 606)”, provides guidance for recognizing gains and losses from the transfer of nonfinancial assets in contracts with noncustomers. The amendments in ASU 2017-05 are effective for public entities for annual reporting periods beginning after December 15, 2017, and for interim periods within that reporting period. Early adoption is permitted for annual reporting periods beginning after December 15, 2016. The Partnership adopted this update as of January 1, 2018, and there was no impact on the Partnership’s financial position, results of operations or cash flows. In May 2017, the FASB issued ASU 2017-09, “Compensation - Stock Compensation (Topic 718): Scope of Modification Accounting.” This update provides clarity and reduces both diversity in practice and cost and complexity when applying the guidance of Topic 718, Compensation - Stock Compensation, to a change in the terms or conditions of a share-based payment award. This update is effective for financial statements issued for annual periods beginning after December 15, 2017, and interim periods within those fiscal years. The Partnership adopted this update as of January 1, 2018, and there was no impact on the Partnership’s financial position, results of operations or cash flows.

QUARTERLY FINANCIAL DATA (Notes

QUARTERLY FINANCIAL DATA (Notes)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Data [Abstract]
Quarterly Financial Information [Text Block]	QUARTERLY FINANCIAL DATA (UNAUDITED) Summarized quarterly financial data is as follows (in thousands, except per unit data): First Quarter Second Quarter Third Quarter Fourth Quarter Full Year 2017: Revenues $ 46,340 $ 43,877 $ 47,474 $ 44,248 $ 181,939 Operating income (loss) (1) 6,557 6,505 12,219 3,559 28,840 Net income (loss) (1) 3,542 6,371 9,771 361 20,045 Basic and diluted net income (loss) per common unit (0.08 ) — 0.08 (0.15 ) (0.15 ) 2018: Revenues (2) $ 44,660 $ 83,493 $ 133,158 $ 123,524 $ 384,835 Operating income (loss) (3) 5,815 6,830 6,663 (46,522 ) (27,214 ) Net income (loss) (3) 4,442 1,785 2,408 (50,682 ) (42,047 ) Basic and diluted net income (loss) per common unit (0.05 ) (0.11 ) (0.09 ) (1.36 ) (1.61 ) ____________________ (1) In April 2017, the Partnership sold the East Texas pipeline system and its investment in Advantage Pipeline. See “Item 7-Management’s Discussion and Analysis” for discussion on the impact these changes had on the Partnership’s consolidated financial statements. (2) The increase in revenue during 2018 is due to an increase in volume in the Partnership’s crude oil marketing business. (3) Operating loss and net loss for the fourth quarter and full year 2018 are impacted by asset impairment charges of $52.4 million .

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Policies (Policy)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Use of Estimates, Policy [Policy Text Block]	USE OF ESTIMATES - The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and disclosure of contingencies. Management makes significant estimates including: (1) allowance for doubtful accounts receivable; (2) estimated useful lives of assets, which impacts depreciation; (3) estimated cash flows and fair values inherent in impairment tests; (4) accruals related to revenues and expenses; (5) the estimated fair value of financial instruments; and (6) liability and contingency accruals. Although management believes these estimates are reasonable, actual results could differ from these estimates.
Cash and Cash Equivalents, Policy [Policy Text Block]	CASH AND CASH EQUIVALENTS - Cash and cash equivalents includes cash and all investments with original maturities of three months or less which are readily convertible into known amounts of cash.
Trade and Other Accounts Receivable, Policy [Policy Text Block]	ACCOUNTS RECEIVABLE - The majority of the Partnership’s accounts receivable relates to its crude oil pipeline services segment, specifically the crude oil marketing business. Accounts receivable included in the consolidated balance sheets are reflected net of the allowance for doubtful accounts of less than $0.1 million at both December 31, 2017 and 2018 . The Partnership reviews all outstanding accounts receivable balances on a monthly basis and records a reserve for amounts that the Partnership expects will not be fully recovered. Although the Partnership considers its allowance for doubtful trade accounts receivable to be adequate, there is no assurance that actual amounts will not vary significantly from estimated amounts.
Property, Plant and Equipment, Policy [Policy Text Block]	PROPERTY, PLANT AND EQUIPMENT - Property, plant and equipment are recorded at cost. Expenditures for maintenance and repairs that do not add capacity or extend the useful life of an asset are expensed as incurred. The carrying values of the assets are based on estimates, assumptions and judgments relative to useful lives and salvage values. As assets are disposed of, the cost and related accumulated depreciation are removed from the accounts, and any resulting gain or loss is included in operating income in the consolidated statements of operations. Depreciation is calculated using the straight-line method based on estimated useful lives of the assets. These estimates are based on various factors, including age (in the case of acquired assets), manufacturing specifications, technological advances and historical data concerning useful lives of similar assets. Uncertainties that impact these estimates include changes in laws and regulations relating to restoration and abandonment requirements, economic conditions and supply and demand in the area. When assets are put into service, management makes estimates with respect to useful lives and salvage values that it believes are reasonable. However, subsequent events could cause management to change its estimates, thus impacting the future calculation of depreciation. The Partnership has contractual obligations to perform dismantlement and removal activities in the event that some of its liquid asphalt cement and residual fuel oil terminalling assets are abandoned (see Note 18 ). Such obligations are recognized in the period incurred if reasonably estimable.
Impairment or Disposal of Long-Lived Assets, Including Intangible Assets, Policy [Policy Text Block]	IMPAIRMENT OF LONG-LIVED ASSETS AND OTHER INTANGIBLE ASSETS - Long-lived assets with recorded values that are not expected to be recovered through future cash flows are written down to estimated fair value. A long-lived asset is tested for impairment when events or circumstances indicate that its carrying value may not be recoverable. The carrying value of a long-lived asset is not recoverable if it exceeds the sum of the undiscounted cash flows expected to result from the use and eventual disposition of the asset. If the carrying value exceeds the sum of the undiscounted cash flows, an impairment loss equal to the amount by which the carrying value exceeds the fair value of the asset is recognized. Fair value is generally determined from estimated discounted future net cash flows. During the year ended December 31, 2018 , the Partnership recognized fixed asset impairment expenses of approximately $40.7 million related to a markdown of our pipeline system to estimated fair value, $1.7 million related to the market value of its pipeline linefill assets and $0.4 million related to the value of obsolete trucking stations in Oklahoma and Colorado. In addition, the Partnership recognized a $10.0 million impairment on a push-down basis related to Ergon’s investment in Cimarron Pipeline. See Note 14 for more information. During the year ended December 31, 2017 , the Partnership recognized fixed asset impairment charges of $1.2 million related to the producer field services business, primarily operated in the Texas panhandle. During the year ended December 31, 2016 , the Partnership recognized fixed asset impairment charges of $25.8 million , primarily due to impairment recognized on the Knight Warrior pipeline project and the East Texas pipeline system. The Knight Warrior pipeline project was canceled due to continued low rig counts in the Eaglebine/Woodbine area coupled with lower production volumes, competing projects and the overall impact of the decreased market price of crude oil. Consequently, shipper commitments related to the project were canceled and an impairment expense of $22.6 million was recognized during the year ended December 31, 2016 . Acquired customer relationships are capitalized and amortized over useful lives ranging from 5 to 20 years using the straight-line method of amortization. An impairment loss is recognized for definite-lived intangibles if the carrying amount of an intangible asset is not recoverable and its carrying amount exceeds its fair value. No impairment charges were recognized during the year ended December 31, 2016 , with respect to intangible assets. During the year ended December 31, 2017 , the Partnership recognized intangible asset impairment charges of $0.2 million on customer relationships related to the former producer field services business, primarily operated in the Texas panhandle. During the year ended December 31, 2018 , the Partnership recognized intangible asset impairment charges of $0.2 million related to a customer contract asset in the crude oil pipeline services business.
Equity Method Investments [Policy Text Block]	EQUITY METHOD INVESTMENTS - The Partnership’s approximate 30% ownership 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 its equity method investee. 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’s share of net income or loss is reflected as one line item on the Partnership’s consolidated statements of operations entitled “Equity earnings in unconsolidated affiliate” and increased or decreased, as applicable, the carrying value of the Partnership’s investment in the unconsolidated affiliate on the consolidated balance sheets. Distributions to the Partnership reduced the carrying value of its investment and are reflected in the Partnership’s consolidated statements of cash flows in the line item “Distributions from unconsolidated affiliate.” In turn, contributions increased the carrying value of the Partnership’s investment and were reflected in the Partnership’s consolidated statements of cash flows in investing activities. See Note 6 for additional information.
Debt, Policy [Policy Text Block]	DEBT ISSUANCE COSTS - Costs incurred in connection with the issuance of long-term debt related to the Partnership’s credit agreement are capitalized and amortized using the straight-line method over the term of the related debt. Use of the straight-line method does not differ materially from the “effective interest” method of amortization.
Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block]	GOODWILL - Goodwill represents the excess of the cost of acquisitions over the amounts assigned to assets acquired and liabilities assumed. Goodwill is not amortized but is tested annually in December for impairment or when events and circumstances warrant an interim evaluation. Goodwill is tested for impairment at a level of reporting referred to as a reporting unit. The Partnership has four reporting units comprised of its (i) asphalt terminalling services, (ii) crude oil terminalling services, (iii) crude oil pipeline services and (iv) crude oil trucking services. If the fair value of a reporting unit exceeds its carrying amount, goodwill of the reporting unit is not considered to be impaired. The impairment test is generally based on the estimated discounted future net cash flows of the respective reporting unit, utilizing discount rates and other factors in determining the fair value of the reporting unit. Inputs in the Partnership’s estimated discounted future net cash flows include existing and estimated future asset utilization, estimated growth rates in future cash flows and estimated terminal values (these are all considered Level 3 inputs). Changes in the carrying amount of goodwill are summarized below for the periods indicated (in thousands): Asphalt Terminalling Services Crude Oil Trucking Services Total Balance, December 31, 2015 $ 3,511 $ 876 $ 4,387 Acquisition 359 — 359 Balance, December 31, 2016 $ 3,870 $ 876 $ 4,746 Impairment — (876 ) (876 ) Balance, December 31, 2017 $ 3,870 $ — $ 3,870 Acquisition 2,858 — 2,858 Balance, December 31, 2018 $ 6,728 $ — $ 6,728 During the fourth quarter of 2017, impairment testing indicated that the fair value of the crude oil trucking services reporting unit was less than the carrying value based on the estimated market value of the crude oil trucking services business, and the Partnership recognized impairment of goodwill of $0.9 million related to this reporting unit. Impairment testing indicated there was no impairment of goodwill in 2016 or in 2018.
Environmental Costs, Policy [Policy Text Block]	ENVIRONMENTAL MATTERS - Liabilities for loss contingencies, including environmental remediation costs, arising from claims, assessments, litigation, fines, penalties and other sources are charged to expense when it is probable that a liability has been incurred and the amount of the assessment and/or remediation can be reasonably estimated. The Partnership had loss contingencies related to environmental matters of $0.1 million and $0.2 million as of December 31, 2017 and 2018 , respectively.
Revenue Recognition, Policy [Policy Text Block]	REVENUE RECOGNITION - On January 1, 2018, the Partnership adopted the new accounting standard ASC 606 - Revenue from Contracts with Customers and all related amendments (“new revenue standard”) using the modified retrospective method, and as a result applied the new guidance only to contracts that are not completed at the adoption date. Results for reporting periods beginning on January 1, 2018, are presented under the new revenue standard, while prior period amounts are not adjusted and continue to be reported in accordance with the Partnership’s historic accounting under ASC 605 - Revenue Recognition . See Note 4 for detailed discussion regarding the Partnership’s revenue recognition policies.
Income Tax, Policy [Policy Text Block]	INCOME AND OTHER TAXES - For federal and most state income tax purposes, the majority of income, gains, losses, deductions and tax credits generated by the Partnership flow through to the unitholders of the Partnership and are subject to income tax at the individual partner level. The Partnership is subject to the Texas state franchise (margin) tax, and the earnings associated with the Partnership’s taxable subsidiary are subject to federal and state income taxes. The Partnership has estimated its liability related to these taxes to be $0.3 million for the year ended 2016 , and $0.2 million for each of the years ended December 31, 2017 and 2018 . This liability is reflected on the Partnership’s consolidated statements of operations as “Provision for income taxes.” See Note 22 for a discussion of certain risks related to the Partnership’s ability to be treated as a partnership for federal income tax purposes.
Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block]	STOCK-BASED COMPENSATION - The Partnership’s general partner adopted the Blueknight Energy Partners G.P. L.L.C. Long-Term Incentive Plan (the “LTIP”). The compensation committee of the Board administers the LTIP. 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 4.1 million common units, subject to adjustment for certain events. Although other types of awards are contemplated under the LTIP, awards issued to date 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. Certain of the phantom unit awards also include distribution equivalent rights (“DERs”). 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. Cash distributions paid on DERs are accounted for as partnership distributions. Recipients of restricted units are entitled to receive cash distributions paid on common units during the vesting period. The Partnership classifies unit award grants as either equity or liability awards. All award grants made under the LTIP from its inception through December 31, 2018 , have been classified as equity awards. Fair value for award grants classified as equity is determined on the grant date of the award and this value is recognized as compensation expense ratably over the requisite service period of unit award grants, which generally is the vesting period. Fair value for equity awards is calculated as the closing price of the Partnership’s common units representing limited partner interests in the Partnership (“common units”) on the grant date and is reduced by the present value of estimated cash distributions to be paid on common units during the vesting period to the extent a unit award does not include DERs. Compensation expense related to unit-based payments is included in operating and general and administrative expenses on the Partnership’s consolidated statements of operations.
Fair Value of Financial Instruments, Policy [Policy Text Block]	FAIR VALUE OF FINANCIAL INSTRUMENTS - The Partnership measures all financial instruments, including derivatives embedded in other contracts, at fair value and recognizes them in the consolidated balance sheets as an asset or a liability, depending on its rights and obligations under the applicable contract. The changes in the fair value of financial instruments are recognized currently in earnings in the consolidated statements of operations.

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Goodwill (Tables)	12 Months Ended
	Dec. 31, 2018
Goodwill [Abstract]
Schedule of Goodwill [Table Text Block]	Changes in the carrying amount of goodwill are summarized below for the periods indicated (in thousands): Asphalt Terminalling Services Crude Oil Trucking Services Total Balance, December 31, 2015 $ 3,511 $ 876 $ 4,387 Acquisition 359 — 359 Balance, December 31, 2016 $ 3,870 $ 876 $ 4,746 Impairment — (876 ) (876 ) Balance, December 31, 2017 $ 3,870 $ — $ 3,870 Acquisition 2,858 — 2,858 Balance, December 31, 2018 $ 6,728 $ — $ 6,728

REVENUE Revenue from Contract w

REVENUE Revenue from Contract with Customer (Tables)	12 Months Ended
	Dec. 31, 2018
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]	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) 2019 $ 28,425 2020 27,296 2021 24,154 2022 16,853 2023 11,444 Thereafter 9,142 Total revenue related to future performance obligations $ 117,314
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): Year ended December 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 $ 18,100 $ 10,966 $ — $ — $ 29,066 Variable throughput revenue 918 962 — — 1,880 Variable reimbursement revenue 7,090 — — — 7,090 Crude oil transportation revenue — — 6,396 14,324 20,720 Crude oil product sales revenue — — 235,428 10 235,438 Related-party revenue: Fixed storage, throughput and other revenue 15,352 — 215 — 15,567 Variable throughput revenue 762 — — — 762 Variable reimbursement revenue 5,572 — 230 — 5,802 Product sales revenue 482 — — — 482 Total revenue from contracts with customers $ 48,276 $ 11,928 $ 242,269 $ 14,334 $ 316,807

EQUITY METHOD INVESTMENT (Table

EQUITY METHOD INVESTMENT (Tables)	12 Months Ended
	Dec. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments [Table Text Block]	Period ended April 3, 2017 Income Statement Operating revenues $ 3,150 Operating expenses $ 465 Net income $ 187

RESTRUCTURING CHARGES (Tables)

RESTRUCTURING CHARGES (Tables)	12 Months Ended
	Dec. 31, 2018
Crude Oil Trucking and Producer Field 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 plan are summarized as follows: Year ended December 31, 2016 2017 2018 (in thousands) Beginning balance $ 1,565 $ 474 $ 286 Cash payments 1,091 188 286 Ending balance $ 474 $ 286 $ —

PROPERTY, PLANT AND EQUIPMENT (

PROPERTY, PLANT AND EQUIPMENT (Tables)	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	Estimated Useful Lives (Years) As of December 31, 2017 2018 (dollars in thousands) Land N/A $ 24,776 $ 24,705 Land improvements 10-20 6,787 5,758 Pipelines and facilities 5-30 166,004 116,155 Storage and terminal facilities 10-35 370,056 321,096 Transportation equipment 3-10 3,293 2,798 Office property and equipment and other 3-20 32,011 26,980 Pipeline linefill and tank bottoms N/A 3,233 10,297 Construction-in-progress N/A 6,500 4,026 Property, plant and equipment, gross 612,660 511,815 Accumulated depreciation (316,591 ) (263,554 ) Property, plant and equipment, net $ 296,069 $ 248,261

INTANGIBLES AND OTHER ASSETS,_2

INTANGIBLES AND OTHER ASSETS, NET (Tables)	12 Months Ended
	Dec. 31, 2018
Intangibles and Other Assets [Abstract]
Schedule of Finite-Lived Intangible Assets [Table Text Block]	other assets, net of accumulated amortization, consist of the following: As of December 31, 2017 2018 (in thousands) Customer relationships $ 12,221 $ 19,214 Deferred charges related to pipeline connection agreements 2,716 2,716 Deposits 302 283 Prepaid insurance 353 248 Other prepaid expenses 103 75 Intangibles and other assets, gross 15,695 22,536 Accumulated amortization of intangible assets (2,782 ) (5,096 ) Intangibles and other assets, net $ 12,913 $ 17,440
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]	The estimated aggregate future amortization expense on amortizable intangible assets currently owned by the Partnership is as follows (in thousands): For year ending: December 31, 2019 $ 2,746 December 31, 2020 2,746 December 31, 2021 2,746 December 31, 2022 2,746 December 31, 2023 1,321 Thereafter 4,529 Total estimated aggregate amortization expense $ 16,834

DEBT Fair Values of Derivative

DEBT Fair Values of Derivative Instruments (Tables)	12 Months Ended
	Dec. 31, 2018
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]	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 Values of Derivatives As of December 31, 2017 2018 Interest rate swap assets - current Other current assets $ 68 $ 44 Interest rate swap liabilities - noncurrent Long-term interest rate swap liabilities $ 225 $ — Changes in the fair value of the interest rate swaps are reflected in the consolidated statements of operations as follows (in thousands): Derivatives Not Designated as Hedging Instruments Location of Gain Recognized in Net Income on Derivatives Amount of Gain Recognized in Net Income on Derivatives Year ended December 31, 2016 2017 2018 Interest rate swaps Interest expense, net of capitalized interest $ 1,156 $ 1,790 $ 201

NET INCOME PER LIMITED PARTNE_2

NET INCOME PER LIMITED PARTNER UNIT (Tables)	12 Months Ended
	Dec. 31, 2018
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): Year ended December 31, 2016 2017 2018 Net income (loss) $ (4,840 ) $ 20,045 $ (42,047 ) General partner interest in net income (loss) 433 944 (512 ) Preferred interest in net income 25,824 25,115 25,115 Net loss available to limited partners $ (31,097 ) $ (6,014 ) $ (66,650 ) Basic and diluted weighted average number of units: Common units 35,093 38,342 40,348 Restricted and phantom units 803 862 1,011 Total units 35,896 39,204 41,359 Basic and diluted net loss per common unit $ (0.87 ) $ (0.15 ) $ (1.61 )

PARTNERS' CAPITAL AND DISTRIB_2

PARTNERS' CAPITAL AND DISTRIBUTIONS Cash Distributions Paid (Tables)	12 Months Ended
	Dec. 31, 2018
Cash Distributions Paid [Abstract]
Distributions Made to Limited Partner, by Distribution [Table Text Block]	The Partnership paid the following distributions on the Preferred Units during the years ended December 31, 2016 , 2017 and 2018 (in thousands): Year Paid Periods Covered Total Paid to Preferred Unitholders Paid to General Partner 2016 Quarters ending December 31, 2015, March 31, 2016, June 30, 2016 and September 30, 2016 $ 22,837 $ 22,449 $ 388 2017 Quarters ending December 31, 2016, March 31, 2017, June 30, 2017 and September 30, 2017 $ 25,534 $ 25,115 $ 420 2018 Quarters ending December 31, 2017, March 31, 2018, June 30, 2018 and September 30, 2018 $ 25,523 $ 25,115 $ 408 In addition, on January 25, 2019 , the Board approved a cash distribution of $0.17875 per outstanding Preferred Unit for the quarter ending December 31, 2018 . The Partnership paid this distribution on the Preferred Units on February 14, 2019 , to unitholders of record as of February 4, 2019 . The total distribution was approximately $6.4 million , with approximately $6.3 million and $0.1 million paid to the Partnership’s preferred unitholders and general partner, respectively. The Partnership paid the following distributions on the common units during the years ended December 31, 2016 , 2017 and 2018 (in thousands): Year Paid Periods Covered Total Paid to Common Unitholders Paid to General Partner Paid to Phantom and Restricted Unitholders Under the LTIP 2016 Quarters ending December 31, 2015, March 31, 2016, June 30, 2016 and September 30, 2016 $ 21,900 $ 20,509 $ 933 $ 458 2017 Quarters ending December 31, 2016, March 31, 2017, June 30, 2017 and September 30, 2017 $ 23,629 $ 22,147 $ 994 $ 488 2018 Quarters ending December 31, 2017, March 31, 2018, June 30, 2018 and September 30, 2018 $ 19,213 $ 18,154 $ 626 $ 433 In addition, on January 25, 2019 , the Board approved a cash distribution of $0.08 per outstanding common unit for the quarter ending December 31, 2018 . The distribution was paid on February 14, 2019 , to unitholders of record as of February 4, 2019 . The total distribution was approximately $3.4 million , with approximately $3.3 million and $0.1 million paid to the Partnership’s common unitholders and general partner, respectively, and $0.1 million paid to holders of phantom and restricted units pursuant to awards granted under the LTIP.

LONG-TERM INCENTIVE PLAN (Table

LONG-TERM INCENTIVE PLAN (Tables)	12 Months Ended
	Dec. 31, 2018
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 grants made to the directors under the LTIP subject to vesting requirements: Grant Date Number of Units Weighted Average Grant Date Fair Value 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 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 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
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 Grant Date Total Fair Value (in thousands) March 2016 416,131 $ 4.77 $ 1,985 October 2016 9,960 $ 5.85 $ 58 March 2017 323,339 $ 7.15 $ 2,312 March 2018 396,536 $ 4.77 $ 1,891
Schedule Of Phantom Common Units And Restricted Common Units Activity	Activity pertaining to phantom common units and restricted common unit awards granted under the LTIP is as follows: Number of Units Weighted Average Grant Date Fair Value Nonvested, December 31, 2017 923,551 $ 6.29 Granted 503,295 4.45 Vested 311,927 6.71 Forfeited 116,700 5.44 Nonvested, December 31, 2018 998,219 $ 5.88

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]	Future non-cancellable commitments related to these items at December 31, 2018 , are summarized below (in thousands): For year ending: Operating Leases December 31, 2019 $ 2,862 December 31, 2020 1,904 December 31, 2021 1,242 December 31, 2022 640 December 31, 2023 548 Thereafter 1,259 Total future minimum lease payments $ 8,455

FAIR VALUE MEASUREMENTS Fair Va

FAIR VALUE MEASUREMENTS Fair Value Measurrements (Tables)	12 Months Ended
	Dec. 31, 2018
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, 2017 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 $ 68 $ — $ 68 $ — Total swap assets $ 68 $ — $ 68 $ — Liabilities: Interest rate swap liabilities $ 225 $ — $ 225 $ — Total swap liabilities $ 225 $ — $ 225 $ — 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 $ —

OPERATING SEGMENTS (Tables)

OPERATING SEGMENTS (Tables)	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	The following table reflects certain financial data for each segment for the periods indicated (in thousands): Year ended December 31, 2016 2017 2018 Asphalt Terminalling Services Service revenue: Third-party revenue $ 75,655 $ 57,486 $ 26,108 Related-party revenue 11,762 56,378 21,686 Lease revenue: Third-party revenue — — 41,319 Related-party revenue — — 25,961 Product sales revenue: Related-party revenue — — 482 Total revenue for reportable segments 87,417 113,864 115,556 Operating expense, excluding depreciation and amortization 30,648 49,241 49,229 Operating margin, excluding depreciation and amortization 56,769 64,623 66,327 Additions to long-lived assets 148,622 22,046 30,068 Total assets (end of period) $ 141,280 $ 146,966 $ 138,245 Crude Oil Terminalling Services Service revenue: Third-party revenue $ 16,387 $ 22,177 $ 11,928 Related-party revenue 7,858 — — Intersegment revenue — — 704 Lease revenue: Third-party revenue — — 45 Total revenue for reportable segments 24,245 22,177 12,677 Operating expense, excluding depreciation and amortization 4,197 4,200 3,899 Operating margin, excluding depreciation and amortization 20,048 17,977 8,778 Additions to long-lived assets 2,126 2,194 3,394 Total assets (end of period) $ 71,689 $ 69,149 $ 68,480 Year ended December 31, 2016 2017 2018 Crude Oil Pipeline Services Service revenue: Third-party revenue $ 8,662 $ 9,580 $ 6,396 Related-party revenue 5,433 310 445 Lease revenue: Third-party revenue — — 484 Product sales revenue: Third-party revenue 20,968 11,094 235,428 Total revenue for reportable segments 35,063 20,984 242,753 Operating expense, excluding depreciation and amortization 15,270 13,310 11,828 Intersegment operating expense 890 417 5,284 Third-party cost of product sales 14,130 8,807 126,776 Related-party cost of product sales — — 102,469 Intersegment cost of product sales 426 150 — Operating margin, excluding depreciation and amortization 4,347 (1,700 ) (3,604 ) Additions to long-lived assets 8,250 2,934 19,654 Total assets (end of period) $ 150,043 $ 117,749 $ 112,429 Crude Oil Trucking Services Service revenue: Third-party revenue $ 25,511 $ 24,529 $ 14,324 Related-party revenue 5,158 — — Intersegment revenue 890 417 4,580 Lease revenue: Third-party revenue — — 219 Product sales revenue: Third-party revenue — 385 10 Intersegment revenue 426 150 — Total revenue for reportable segments 31,985 25,481 19,133 Operating expense, excluding depreciation and amortization 30,156 25,915 19,575 Operating margin, excluding depreciation and amortization 1,829 (434 ) (442 ) Additions to long-lived assets 2,558 1,701 3,243 Total assets (end of period) $ 12,651 $ 7,005 $ 4,150 Total operating margin, excluding depreciation and amortization (1) $ 82,993 $ 80,466 $ 71,059 Total segment revenues 178,710 182,506 390,119 Elimination of intersegment revenues (1,316 ) (567 ) (5,284 ) Consolidated revenues 177,394 181,939 384,835 ____________________ (1) The following table reconciles segment operating margin, excluding depreciation and amortization to income (loss) before income taxes (in thousands): Year ended December 31, 2016 2017 2018 Operating margin (excluding depreciation and amortization) $ 82,993 $ 80,466 $ 71,059 Depreciation and amortization (30,820 ) (31,139 ) (29,359 ) General and administrative expenses (20,029 ) (17,112 ) (15,995 ) Asset impairment expense (25,761 ) (2,400 ) (53,068 ) Gain (loss) on sale of assets 108 (975 ) 149 Equity earnings in unconsolidated affiliate 1,483 61 — Gain on sale of unconsolidated affiliate — 5,337 2,225 Interest expense (12,554 ) (14,027 ) (16,860 ) Income (loss) before income taxes $ (4,580 ) $ 20,211 $ (41,849 )

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Schedule of Deferred Tax Assets	As a result, the Partnership revalued the deferred tax effects of the temporary differences between its taxable subsidiary’s tax basis of assets and liabilities and the financial reporting amounts at December 31, 2017 , which resulted in a reduction of the taxable subsidiary’s gross deferred tax asset of $0.3 million . The net deferred tax effect of the taxable entity’s temporary differences at December 31, 2018 , are presented below (in thousands): Deferred Tax Asset Difference in bases of property, plant and equipment $ 273 Deferred tax asset 273 Less: valuation allowance (273 ) Net deferred tax asset $ —

QUARTERLY FINANCIAL DATA (Table

QUARTERLY FINANCIAL DATA (Tables)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Data [Abstract]
Quarterly Financial Information [Table Text Block]	Summarized quarterly financial data is as follows (in thousands, except per unit data): First Quarter Second Quarter Third Quarter Fourth Quarter Full Year 2017: Revenues $ 46,340 $ 43,877 $ 47,474 $ 44,248 $ 181,939 Operating income (loss) (1) 6,557 6,505 12,219 3,559 28,840 Net income (loss) (1) 3,542 6,371 9,771 361 20,045 Basic and diluted net income (loss) per common unit (0.08 ) — 0.08 (0.15 ) (0.15 ) 2018: Revenues (2) $ 44,660 $ 83,493 $ 133,158 $ 123,524 $ 384,835 Operating income (loss) (3) 5,815 6,830 6,663 (46,522 ) (27,214 ) Net income (loss) (3) 4,442 1,785 2,408 (50,682 ) (42,047 ) Basic and diluted net income (loss) per common unit (0.05 ) (0.11 ) (0.09 ) (1.36 ) (1.61 ) ____________________ (1) In April 2017, the Partnership sold the East Texas pipeline system and its investment in Advantage Pipeline. See “Item 7-Management’s Discussion and Analysis” for discussion on the impact these changes had on the Partnership’s consolidated financial statements. (2) The increase in revenue during 2018 is due to an increase in volume in the Partnership’s crude oil marketing business. (3) Operating loss and net loss for the fourth quarter and full year 2018 are impacted by asset impairment charges of $52.4 million .

ORGANIZATION AND NATURE OF BU_2

ORGANIZATION AND NATURE OF BUSINESS (Narrative) (Details) $ in Thousands	Oct. 05, 2016USD ($)shares	Dec. 31, 2018Operating-segmentsStatesshares	Dec. 31, 2018USD ($)Statesshares	Dec. 31, 2018Statesshares	Dec. 31, 2017USD ($)shares	Dec. 31, 2016USD ($)shares
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Proceeds from issuance of common units in private placement | $						$ 5,000
Repurchase of Preferred Units | $			$ 0		$ 0	95,348
Preferred Units, outstanding		35,125,202	35,125,202	35,125,202	35,125,202
Combination of Entities under Common Control, Consideration Paid in Excess of Historical Cost | $					$ 3,725	$ 91,251
Number of states in which entity operates (in states) | States		27	27	27
Number of Operating Segments		4		4
Blueknight GP Holding, LLC [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	100.00%
General Partner [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	100.00%
Preferred Partner [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Combination of Entities under Common Control, Shares Issued	18,312,968
Preferred Units repurchased during period						13,335,390
Repurchase of Preferred Units | $	$ 95,348					$ 95,348
Preferred Partner [Member] | Charlesbank [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Preferred Units repurchased during period	6,667,695
Preferred Units, outstanding	2,488,789
Preferred Partner [Member] | Vitol [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Preferred Units repurchased during period	6,667,695
Preferred Units, outstanding	2,488,789
Limited Partner [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Proceeds from issuance of common units in private placement | $	$ 5,000					$ 5,000
Ergon [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Combination of Entities under Common Control, Cash Received | $	$ 22,100

SUMMARY OF SIGNIFICANT ACCOUN_4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) shares in Millions	12 Months Ended
	Dec. 31, 2018USD ($)shares	Dec. 31, 2018USD ($)Operating-segmentsshares	Dec. 31, 2018USD ($)shares	Dec. 31, 2018USD ($)shares	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Apr. 03, 2017	Dec. 31, 2015USD ($)
Accounting Policies [Line Items]
Accounts receivable, allowance for doubtful accounts	$ 26,000	$ 26,000	$ 26,000	$ 26,000	$ 28,000
Fixed asset impairment charge			42,860,000		1,293,000	$ 25,761,000
Other Asset Impairment Charges			10,019,000		0	0
Impairment of intangible assets						0
Number of Operating Segments		4		4
Goodwill	6,728,000	$ 6,728,000	6,728,000	$ 6,728,000	3,870,000	4,700,000		$ 4,387,000
Goodwill, Acquired During Period			2,858,000			359,000
Goodwill, Impairment Loss			0		876,000	0
Accrual for Environmental Loss Contingencies	$ 200,000	$ 200,000	200,000	$ 200,000	100,000
Provision for income taxes			198,000		166,000	260,000
Customer Relationships [Member] | Minimum [Member]
Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years
Customer Relationships [Member] | Maximum [Member]
Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years
State and Local Jurisdiction [Member]
Accounting Policies [Line Items]
Provision for income taxes			$ 200,000		200,000	300,000
Blueknight Energy Partners G.P., L.L.C. Long-Term Incentive Plan [Member]
Accounting Policies [Line Items]
Number of units authorized | shares	4.1	4.1	4.1	4.1
Asphalt Terminalling Services [Member]
Accounting Policies [Line Items]
Goodwill	$ 6,728,000	$ 6,728,000	$ 6,728,000	$ 6,728,000	3,870,000	3,870,000		3,500,000
Goodwill, Acquired During Period			2,858,000			359,000
Goodwill, Impairment Loss					0
Crude Oil Trucking Services [Member]
Accounting Policies [Line Items]
Goodwill	$ 0	$ 0	0	$ 0	0	876,000		$ 876,000
Goodwill, Acquired During Period			0			0
Goodwill, Impairment Loss					(876,000)
Oklahoma [Member] | Crude Oil Pipeline Services [Member] | Pipelines and Facilities
Accounting Policies [Line Items]
Fixed asset impairment charge			40,700,000
Oklahoma [Member] | Crude Oil Pipeline Services [Member] | Pipeline linefill and tank bottoms
Accounting Policies [Line Items]
Fixed asset impairment charge			1,719,000
Texas [Member] | Crude Oil Pipeline Services [Member] | Customer Contracts [Member]
Accounting Policies [Line Items]
Impairment of intangible assets			200,000
Texas [Member] | Crude Oil Trucking Services [Member] | Producer Field Services [Member]
Accounting Policies [Line Items]
Fixed asset impairment charge					1,248,000
Texas [Member] | Crude Oil Trucking Services [Member] | Customer Relationships [Member]
Accounting Policies [Line Items]
Impairment of intangible assets					$ 231,000
Oklahoma and Colorado [Member] | Crude Oil Trucking Services [Member] | Storage and terminal facilities
Accounting Policies [Line Items]
Fixed asset impairment charge			384,000
Advantage Pipeline, L.L.C. [Member]
Accounting Policies [Line Items]
Equity Method Investment, Ownership Percentage							30.00%
Knight Warrior Pipeline Project [Member] | Texas [Member] | Crude Oil Pipeline Services [Member] | Pipelines [Member]
Accounting Policies [Line Items]
Fixed asset impairment charge						$ 22,600,000
Cimarron Express [Member] | Ergon [Member]
Accounting Policies [Line Items]
Other Asset Impairment Charges			$ 10,019,000

SUMMARY OF SIGNIFICANT ACCOUN_5

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Goodwill (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Line Items]
Goodwill	$ 6,728,000	$ 3,870,000	$ 4,700,000	$ 4,387,000
Goodwill, Acquired During Period	2,858,000		359,000
Goodwill, Impairment Loss	0	(876,000)	0
Asphalt Terminalling Services [Member]
Goodwill [Line Items]
Goodwill	6,728,000	3,870,000	3,870,000	3,500,000
Goodwill, Acquired During Period	2,858,000		359,000
Goodwill, Impairment Loss		0
Crude Oil Trucking Services [Member]
Goodwill [Line Items]
Goodwill	0	0	876,000	$ 876,000
Goodwill, Acquired During Period	$ 0		$ 0
Goodwill, Impairment Loss		$ 876,000

REVENUE Narrative (Details)

REVENUE Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Third-party revenue	$ 58,756	$ 113,772	$ 126,215
Accounts receivable, net of allowance for doubtful accounts of $28 and $26 at December 31, 2017 and 2018, respectively	35,683	7,589
Revenue related to future performance obligations	117,314
Billed contract accounts receivable	34,600	8,500
Contract with Customer, Asset, Net, Current	0	0
Contract with Customer, Liability, Noncurrent	5,900	3,700
Operating Lease, Variable Lease Income	5,100	4,400	4,400
Movement in Deferred Revenue [Roll Forward]
Deferred revenue, additions	4,000
Contract with customer, liability, revenue recognized	(1,800)
Variable Throughput Revenue [Member]
Third-party revenue	1,880
Variable Reimbursement Revenue [Member]
Third-party revenue	7,090
Crude Oil Transportation Revenue [Member]
Third-party revenue	20,720
Asphalt Terminalling Services [Member]
Third-party revenue	26,108	57,486	75,655
Asphalt Terminalling Services [Member] | Variable Throughput Revenue [Member]
Third-party revenue	$ 918
Revenue, Performance Obligation, Description of Payment Terms	P30D
Asphalt Terminalling Services [Member] | Variable Reimbursement Revenue [Member]
Third-party revenue	$ 7,090
Revenue, Performance Obligation, Description of Payment Terms	P30D
Asphalt Terminalling Services [Member] | Crude Oil Transportation Revenue [Member]
Third-party revenue	$ 0
Crude Oil Terminalling Services [Member]
Third-party revenue	11,928	22,177	16,387
Crude Oil Terminalling Services [Member] | Variable Throughput Revenue [Member]
Third-party revenue	$ 962
Revenue, Performance Obligation, Description of Payment Terms	P30D
Crude Oil Terminalling Services [Member] | Variable Reimbursement Revenue [Member]
Third-party revenue	$ 0
Crude Oil Terminalling Services [Member] | Crude Oil Transportation Revenue [Member]
Third-party revenue	0
Crude Oil Pipeline Services [Member]
Third-party revenue	6,396	9,580	8,662
Crude Oil Pipeline Services [Member] | Variable Throughput Revenue [Member]
Third-party revenue	0
Crude Oil Pipeline Services [Member] | Variable Reimbursement Revenue [Member]
Third-party revenue	0
Crude Oil Pipeline Services [Member] | Crude Oil Transportation Revenue [Member]
Third-party revenue	$ 6,396
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	$ 14,324	$ 24,529	$ 25,511
Crude Oil Trucking Services [Member] | Variable Throughput Revenue [Member]
Third-party revenue	0
Crude Oil Trucking Services [Member] | Variable Reimbursement Revenue [Member]
Third-party revenue	0
Crude Oil Trucking Services [Member] | Crude Oil Transportation Revenue [Member]
Third-party revenue	$ 14,324
Revenue, Performance Obligation, Description of Payment Terms	P30D

REVENUE Revenue Related to Futu

REVENUE Revenue Related to Future Performance Obligations Due by Period (Details) $ in Thousands	Dec. 31, 2018USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	$ 117,314
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	28,425
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	27,296
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	24,154
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	16,853
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	11,444
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	$ 9,142

REVENUE Disaggregation of Reven

REVENUE Disaggregation of Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Third-party revenue	$ 58,756	$ 113,772	$ 126,215
Third-party revenue, product sales	235,438	11,479	20,968
Related-party revenue	482	0	0
Revenue from contract with customer	316,807
Fixed Storage and Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	29,066
Related-party revenue	15,567
Variable Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	1,880
Related-party revenue	762
Variable Reimbursement Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	7,090
Related-party revenue	5,802
Asphalt Product Sales Revenue [Member] [Member]
Disaggregation of Revenue [Line Items]
Related-party revenue	482
Crude Oil Transportation Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	20,720
Crude Oil Product Sales Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue, product sales	235,438
Asphalt Terminalling Services [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	26,108	57,486	75,655
Third-party revenue, product sales	482	0	0
Revenue from contract with customer	48,276
Asphalt Terminalling Services [Member] | Fixed Storage and Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	18,100
Related-party revenue	15,352
Asphalt Terminalling Services [Member] | Variable Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	918
Related-party revenue	762
Asphalt Terminalling Services [Member] | Variable Reimbursement Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	7,090
Related-party revenue	5,572
Asphalt Terminalling Services [Member] | Asphalt Product Sales Revenue [Member] [Member]
Disaggregation of Revenue [Line Items]
Related-party revenue	482
Asphalt Terminalling Services [Member] | Crude Oil Transportation Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0
Asphalt Terminalling Services [Member] | Crude Oil Product Sales Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue, product sales	0
Crude Oil Terminalling Services [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	11,928	22,177	16,387
Revenue from contract with customer	11,928
Crude Oil Terminalling Services [Member] | Fixed Storage and Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	10,966
Related-party revenue	0
Crude Oil Terminalling Services [Member] | Variable Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	962
Related-party revenue	0
Crude Oil Terminalling Services [Member] | Variable Reimbursement Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0
Related-party revenue	0
Crude Oil Terminalling Services [Member] | Asphalt Product Sales Revenue [Member] [Member]
Disaggregation of Revenue [Line Items]
Related-party revenue	0
Crude Oil Terminalling Services [Member] | Crude Oil Transportation Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0
Crude Oil Terminalling Services [Member] | Crude Oil Product Sales Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue, product sales	0
Crude Oil Pipeline Services [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	6,396	9,580	8,662
Third-party revenue, product sales	235,428	11,094	20,968
Revenue from contract with customer	242,269
Crude Oil Pipeline Services [Member] | Fixed Storage and Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0
Related-party revenue	215
Crude Oil Pipeline Services [Member] | Variable Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0
Related-party revenue	0
Crude Oil Pipeline Services [Member] | Variable Reimbursement Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0
Related-party revenue	230
Crude Oil Pipeline Services [Member] | Asphalt Product Sales Revenue [Member] [Member]
Disaggregation of Revenue [Line Items]
Related-party revenue	0
Crude Oil Pipeline Services [Member] | Crude Oil Transportation Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	6,396
Crude Oil Pipeline Services [Member] | Crude Oil Product Sales Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue, product sales	235,428
Crude Oil Trucking Services [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	14,324	24,529	25,511
Third-party revenue, product sales	10	$ 385	$ 0
Revenue from contract with customer	14,334
Crude Oil Trucking Services [Member] | Fixed Storage and Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0
Related-party revenue	0
Crude Oil Trucking Services [Member] | Variable Throughput Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0
Related-party revenue	0
Crude Oil Trucking Services [Member] | Variable Reimbursement Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	0
Related-party revenue	0
Crude Oil Trucking Services [Member] | Asphalt Product Sales Revenue [Member] [Member]
Disaggregation of Revenue [Line Items]
Related-party revenue	0
Crude Oil Trucking Services [Member] | Crude Oil Transportation Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue	14,324
Crude Oil Trucking Services [Member] | Crude Oil Product Sales Revenue [Member]
Disaggregation of Revenue [Line Items]
Third-party revenue, product sales	$ 10

REVENUE Minimum Future Annual L

REVENUE Minimum Future Annual Lease Rentals Due by Period (Details) $ in Thousands	Dec. 31, 2018USD ($)
Operating Leases, Future Minimum Payments Receivable [Abstract]
Operating Leases, Future Minimum Payments Receivable, Current	$ 47,732
Operating Leases, Future Minimum Payments Receivable, in Two Years	42,890
Operating Leases, Future Minimum Payments Receivable, in Three Years	38,873
Operating Leases, Future Minimum Payments Receivable, in Four Years	28,190
Operating Leases, Future Minimum Payments Receivable, in Five Years	19,248
Operating Leases, Future Minimum Payments Receivable, Thereafter	22,342
Operating Leases, Future Minimum Payments Receivable	$ 199,275

ACQUISITIONS Narrative (Details

ACQUISITIONS Narrative (Details) $ in Thousands	Dec. 01, 2017USD ($)shares	Oct. 05, 2016USD ($)Terminalling_And_Storage_Facilities	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Business Acquisition [Line Items]
Combination of Entities under Common Control, Consideration Paid in Excess of Historical Cost				$ 3,725	$ 91,251
Payments to Acquire Businesses, Gross			$ 21,959	$ 0	18,989
Ergon [Member]
Business Acquisition [Line Items]
Combination of Entities under Common Control, Consideration Transferred	$ 10,200
Combination of Entities under Common Control, Historical Cost of Assets Acquired	6,400	$ 31,300
Combination of Entities under Common Control, Accumulated Depreciation on Assets Acquired	7,900	63,000
Combination of Entities under Common Control, Consideration Paid in Excess of Historical Cost	$ 3,700	$ 91,300
Combination of Entities under Common Control, Number of Asphalt Facilities Acquired | Terminalling_And_Storage_Facilities		9
Ergon [Member] | Limited Partner [Member]
Business Acquisition [Line Items]
Combination of Entities under Common Control, Shares Issued | shares	1,898,380
Virginia & North Carolina [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross					$ 18,989
Oklahoma [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross			$ 22,000

EQUITY METHOD INVESTMENT (Detai

EQUITY METHOD INVESTMENT (Details) - USD ($) $ in Thousands	Jan. 02, 2018	Apr. 03, 2017	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Schedule of Equity Method Investments [Line Items]
Proceeds from sale of unconsolidated affiliate				$ 2,225	$ 26,489	$ 0
Equity Method Investment, Realized Gain (Loss) on Disposal				$ 2,225	$ 5,337	$ 0
Advantage Pipeline, L.L.C. [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage		30.00%
Equity Method Investment, Summarized Financial Information, Revenue		$ 3,150
Equity Method Investment, Summarized Financial Information, Cost of Sales		465
Equity Method Investment, Summarized Financial Information, Net Income (Loss)		187
Proceeds from sale of unconsolidated affiliate	$ 2,200	25,300	$ 1,100
Equity Method Investment, Realized Gain (Loss) on Disposal		$ 4,200
Proceeds from Sale of Equity Method Investment, Percent Held In Escrow		10.00%
Advantage Pipeline, L.L.C. [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage		30.00%
Customer Concentration Risk [Member] | Minimum [Member]
Schedule of Equity Method Investments [Line Items]
Concentration Risk, Percentage				10.00%

RESTRUCTURING CHARGES (Details)

RESTRUCTURING CHARGES (Details) - Crude Oil Trucking Services [Member] - West Texas Trucking Market Exit Plan [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	$ 0	$ 286	$ 474	$ 1,565
Payments for Restructuring	$ 286	$ 188	$ 1,091

PROPERTY, PLANT AND EQUIPMENT_2

PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	Jul. 13, 2018	Apr. 24, 2018	Dec. 01, 2017	Apr. 18, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property Subject to or Available for Operating Lease, Gross					$ 280,300
Property Subject to or Available for Operating Lease, Accumulated Depreciation					170,200
Property, plant and equipment, gross					511,815	$ 612,660
Property, plant and equipment, accumulated depreciation and impairments					263,554	316,591
Property, plant and equipment, net					248,261	296,069
Depreciation					26,900	29,900	$ 29,600
Fixed asset impairment charge					42,860	1,293	25,761
Other Asset Impairment Charges					10,019	0	0
Payments to Acquire Businesses, Gross					21,959	0	$ 18,989
Value of stock issued during period for acquisitions						10,156
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross					24,705	24,776
Land improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross					$ 5,758	6,787
Land improvements | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives					10 years
Land improvements | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives					20 years
Pipelines and Facilities
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross					$ 116,155	166,004
Pipelines and Facilities | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives					5 years
Pipelines and Facilities | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives					30 years
Storage and terminal facilities
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross					$ 321,096	370,056
Storage and terminal facilities | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives					10 years
Storage and terminal facilities | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives					35 years
Transportation equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross					$ 2,798	3,293
Transportation equipment | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives					3 years
Transportation equipment | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives					10 years
Office property and equipment and other
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross					$ 26,980	32,011
Office property and equipment and other | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives					3 years
Office property and equipment and other | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives					20 years
Pipeline linefill and tank bottoms
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross					$ 10,297	3,233
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross					4,026	$ 6,500
Asphalt Terminalling Services [Member]
Property, Plant and Equipment [Line Items]
Proceeds from Sale of Property Held-for-sale	$ 90,000
Texas [Member] | Crude Oil Pipeline Services [Member]
Property, Plant and Equipment [Line Items]
Proceeds from Sale of Property Held-for-sale				$ 4,800
Gain (Loss) on Disposition of Assets				$ 100
Texas [Member] | Crude Oil Trucking Services [Member]
Property, Plant and Equipment [Line Items]
Proceeds from Sale of Property Held-for-sale		$ 3,000
Gain (Loss) on Disposition of Assets		$ 400
Oklahoma and Colorado [Member] | Storage and terminal facilities | Crude Oil Trucking Services [Member]
Property, Plant and Equipment [Line Items]
Fixed asset impairment charge					384
Oklahoma [Member]
Property, Plant and Equipment [Line Items]
Payments to Acquire Businesses, Gross					22,000
Oklahoma [Member] | Pipelines and Facilities | Crude Oil Pipeline Services [Member]
Property, Plant and Equipment [Line Items]
Fixed asset impairment charge					40,700
Oklahoma [Member] | Pipeline linefill and tank bottoms | Crude Oil Pipeline Services [Member]
Property, Plant and Equipment [Line Items]
Fixed asset impairment charge					$ 1,719
Limited Partner [Member]
Property, Plant and Equipment [Line Items]
Common units issued for acquisitions						1,898,380
Ergon [Member] | Limited Partner [Member]
Property, Plant and Equipment [Line Items]
Common units issued for acquisitions			1,898,380
Value of stock issued during period for acquisitions			$ 10,200

INTANGIBLES AND OTHER ASSETS,_3

INTANGIBLES AND OTHER ASSETS, NET Narrative (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Feb. 29, 2016	Nov. 30, 2015	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Intangibles and other assets, net			$ 17,440	$ 12,913
Impairment of intangible assets					$ 0
Amortization of Intangible Assets			2,500	1,300	$ 1,200
Asphalt Terminalling Services [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 8,400		$ 7,600
Crude Oil Pipeline Services [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired		$ 3,200
Minimum [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life			5 years
Maximum [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life			20 years
Crude Oil Trucking Services [Member] | Texas [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of intangible assets				$ 231
Crude Oil Pipeline Services [Member] | Texas [Member] | Customer Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of intangible assets			$ 200

INTANGIBLES AND OTHER ASSETS,_4

INTANGIBLES AND OTHER ASSETS, NET Other Assets, Net of Accumulated Depreciation (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
INTANGIBLE AND OTHER ASSETS, NET [Abstract]
Customer relationships	$ 19,214	$ 12,221
Deferred charges related to pipeline connection agreements	2,716	2,716
Deposits	283	302
Prepaid insurance	248	353
Other prepaid expenses	75	103
Intangibles and other assets, gross	22,536	15,695
Accumulated amortization of intangible assets	(5,096)	(2,782)
Intangibles and other assets, net	$ 17,440	$ 12,913

INTANGIBLES AND OTHER ASSETS,_5

INTANGIBLES AND OTHER ASSETS, NET Estimated Aggregate Amortization Expense on Intangible Assets (Details) $ in Thousands	Dec. 31, 2018USD ($)
For the twelve months ending:
December 31, 2019	$ 2,746
December 31, 2020	2,746
December 31, 2021	2,746
December 31, 2022	2,746
December 31, 2023	1,321
Thereafter	4,529
Total estimated aggregate amortization expense	$ 16,834

DEBT (Credit Agreements) (Detai

DEBT (Credit Agreements) (Details)	Mar. 12, 2019USD ($)	May 11, 2017USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Mar. 11, 2019USD ($)	Jun. 28, 2018USD ($)	Dec. 31, 2015USD ($)
Debt Instrument [Line Items]
Cash and cash equivalents			$ 1,455,000	$ 1,455,000	$ 2,469,000	$ 3,304,000			$ 3,038,000
Long-term Debt, Excluding Current Maturities			265,592,000	265,592,000	307,592,000
Maximum quarterly distribution			10,700,000
Write-off of deferred debt issuance costs		$ 700,000		400,000
Debt issuance costs, net			3,349,000	3,349,000	4,442,000
Payments of debt issuance costs				358,000	4,208,000	956,000
Amortization of debt issuance costs				$ 1,000,000	$ 1,100,000	$ 1,100,000
Debt Instrument, Interest Rate During Period				5.49%	4.43%	3.95%
Interest expense for long-term debt				$ 16,800,000	$ 13,800,000	$ 11,200,000
Interest Rate Swaps, Notional Amount			100,000,000	100,000,000	200,000,000
Other long-term liabilities			0	$ 0	225,000
Subsequent Event [Member]
Debt Instrument [Line Items]
Repayments of Lines of Credit	$ 14,000,000
Blueknight General Partners G. P., L.L.C. [Member]
Debt Instrument [Line Items]
Credit agreement, Constitute a change of control, if ceases to own, directly or indirectly, exactly 50% of the membership interests of the General Partner or if General Partner ceases to be controlled (as a percent)				100.00%
Ergon [Member]
Debt Instrument [Line Items]
Credit agreement, Constitute a change of control if Ergon ceases to own and control 50% of the GP				50.00%
Letter of Credit [Member] | Subsequent Event [Member]
Debt Instrument [Line Items]
Letters of credit outstanding, amount							$ 1,200,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Revolving credit facility amount			400,000,000	$ 400,000,000				$ 450,000,000
Maximum borrowing capacity including additional lenders			$ 600,000,000	$ 600,000,000
Debt Instrument Maximum Covenant Consolidated Senior Secured Leverage Ratio			3.50	3.50
Consolidated interest coverage (as a ratio), minimum permitted			2.50	2.50
Consolidated total leverage (as a ratio), actual			5.09	5.09
Consolidated interest coverage (as a ratio), actual			3.34	3.34
Debt issuance costs, net		$ 900,000
Payments of debt issuance costs				$ 400,000	4,200,000	$ 1,000,000
Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Unused capacity, commitment fee (as a percent)				0.375%
Debt Instrument Covenant, Issued Qualified Senior Notes			$ 200,000,000	$ 200,000,000
Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Unused capacity, commitment fee (as a percent)				0.50%
Revolving Credit Facility [Member] | Subsequent Event [Member]
Debt Instrument [Line Items]
Long-term Line of Credit							253,600,000
Unused borrowing capacity							$ 145,200,000
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] | Minimum [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] | Maximum [Member]
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] | Minimum [Member]
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] | Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)				3.25%
Aggregate Principal Below Threshold [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument Covenant, Issued Qualified Senior Notes			200,000,000	$ 200,000,000
Minimum Acquisition Costs				15,000,000
Aggregate Principal Above Threshold [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument Covenant, Issued Qualified Senior Notes			$ 200,000,000	$ 200,000,000
Provision One, Applicable Period Four [Domain] | Aggregate Principal Below Threshold [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Consolidated total leverage (as a ratio), Maximum permitted			4.75	4.75
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			5.50	5.50
Provision One, 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			5.50	5.50
Provision One, Applicable Period Two [Member] | Aggregate Principal Below Threshold [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Consolidated total leverage (as a ratio), Maximum permitted			5.25	5.25
Provision One, Applicable Period Three [Member] [Domain] | Aggregate Principal Below Threshold [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Consolidated total leverage (as a ratio), Maximum permitted			5	5
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	5.25
Provision Two, 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	5
Fair Value, Inputs, Level 2 [Member]
Debt Instrument [Line Items]
Other long-term liabilities					$ 225,000

DEBT Derivative Instruments (De

DEBT Derivative Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 28, 2018
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest Rate Swaps, Notional Amount	$ 100,000	$ 200,000
Notional Amount, Expired				$ 100,000
Interest Rate Swaps Interest Expense		1,300	$ 2,500
Unrealized Gain (Loss) on Derivatives	201	1,790	$ 1,156
Interest Income, Other	100
Other Current Assets [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest Rate Swap Assets - Current	44	68
Other Noncurrent Liabilities [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest Rate Swap Liabilities - Noncurrent	$ 0	$ 225

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								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Net income (loss)	$ (50,682)	$ 2,408	$ 1,785	$ 4,442	$ 361	$ 9,771	$ 6,371	$ 3,542	$ (42,047)	$ 20,045	$ (4,840)
General partner interest in net income									(512)	944	433
Preferred interest in net income									25,115	25,115	25,824
Net loss available to limited partners									$ (66,650)	$ (6,014)	$ (31,097)
Basic and diluted weighted average number of units:
Common units									40,348	38,342	35,093
Restricted and phantom units									1,011	862	803
Total units									41,359	39,204	35,896
Basic and diluted net loss per common unit	$ (1.36)	$ (0.09)	$ (0.11)	$ (0.05)	$ (0.15)	$ 0.08	$ 0	$ (0.08)	$ (1.61)	$ (0.15)	$ (0.87)

PARTNERS' CAPITAL AND DISTRIB_3

PARTNERS' CAPITAL AND DISTRIBUTIONS Issuance Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 01, 2017	Oct. 05, 2016	Jul. 26, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Capital Unit [Line Items]
Value of stock issued during period for acquisitions					$ 10,156
Proceeds from issuance of common units in private placement						$ 5,000
Proceeds from issuance of common units, net of offering costs						20,931
Repurchase of Preferred Units				$ 0	$ 0	95,348
Preferred Units, outstanding				35,125,202	35,125,202
Proceeds from issuance of Preferred Units						144,672
Partners' capital account, sale of units						$ 680
Preferred Partner [Member]
Capital Unit [Line Items]
Preferred Units repurchased during period						13,335,390
Partners' capital account, units issued						18,312,968
Repurchase of Preferred Units		$ 95,348				$ 95,348
Limited Partner [Member]
Capital Unit [Line Items]
Common units issued for acquisitions					1,898,380
Issuance of common units in private placement						847,457
Proceeds from issuance of common units in private placement		$ 5,000				$ 5,000
Proceeds from issuance of common units, net of offering costs			$ 20,931			$ 20,931
Limited partners' offering costs			$ 1,500
Partners' capital account, units issued			3,795,000			3,795,000
Sale of stock, price per share			$ 5.90
General Partner [Member]
Capital Unit [Line Items]
Partners' capital account, units issued						97,654
Partners' capital account, sale of units						$ 680
Charlesbank [Member] | Preferred Partner [Member]
Capital Unit [Line Items]
Preferred Units repurchased during period		6,667,695
Preferred Units, outstanding		2,488,789
Vitol [Member] | Preferred Partner [Member]
Capital Unit [Line Items]
Preferred Units repurchased during period		6,667,695
Preferred Units, outstanding		2,488,789
Ergon [Member] | Preferred Partner [Member]
Capital Unit [Line Items]
Partners' capital account, units issued		18,312,968
Partners' capital account, sale of units		$ 144,700
Ergon [Member] | Limited Partner [Member]
Capital Unit [Line Items]
Issuance of common units in private placement		847,457
Ergon [Member] | General Partner [Member]
Capital Unit [Line Items]
Partners' capital account, units issued		97,654
Partners' capital account, sale of units		$ 700
Ergon [Member] | Limited Partner [Member]
Capital Unit [Line Items]
Common units issued for acquisitions	1,898,380
Value of stock issued during period for acquisitions	$ 10,200
Proceeds from issuance of common units in private placement		$ 5,000

PARTNERS' CAPITAL AND DISTRIB_4

PARTNERS' CAPITAL AND DISTRIBUTIONS Distribution Allocations Narrative (Details)	12 Months Ended
	Dec. 31, 2018$ / shares
Preferred Partner [Member]
Quarterly distribution, per Preferred Unit per quarter	$ 0.17875
Preferred Partner [Member] | First Tier Cash Distribution - Preferred Units Quarterly Distribution [Member]
Partners' capital account, distributions, allocation percentage	98.40%
Preferred Partner [Member] | Second Tier Cash Distribution - Preferred Units Arrearages [Member]
Partners' capital account, distributions, allocation percentage	98.40%
Limited Partner [Member]
Minimum distribution, per common unit per quarter	$ 0.11
Limited Partner [Member] | Third Tier Cash Distribution - After Preferred Units Minimum [Member]
Partners' capital account, distributions, allocation percentage	98.40%
General Partner [Member] | First Tier Cash Distribution - Preferred Units Quarterly Distribution [Member]
Partners' capital account, distributions, allocation percentage	1.60%
General Partner [Member] | Second Tier Cash Distribution - Preferred Units Arrearages [Member]
Partners' capital account, distributions, allocation percentage	1.60%
General Partner [Member] | Third Tier Cash Distribution - After Preferred Units Minimum [Member]
Partners' capital account, distributions, allocation percentage	1.60%
First Tier Incentive Distribution Rights Percentage Increase[Member] | General Partner [Member]
Incentive distribution rights, percentage	13.00%
Second Tier Incentive Distribution Rights Percentage [Member] | General Partner [Member]
Incentive distribution rights, percentage	23.00%
Third Tier Incentive Distribution Rights Percentage [Member] | General Partner [Member]
Incentive distribution rights, percentage	48.00%
First Tier Target Distribution [Member] | Limited Partner [Member]
Partners' capital account, distributions, allocation percentage	98.40%
First Tier Target Distribution [Member] | General Partner [Member]
Partners' capital account, distributions, allocation percentage	1.60%
First Tier Target Distribution [Member] | Limited and General Partners [Member]
Target quarterly distribution	$ 0.1265
Second Tier Target Distribution [Member] | Limited Partner [Member]
Partners' capital account, distributions, allocation percentage	85.40%
Second Tier Target Distribution [Member] | General Partner [Member]
Partners' capital account, distributions, allocation percentage	14.60%
Second Tier Target Distribution [Member] | Limited and General Partners [Member]
Target quarterly distribution	$ 0.1375
Third Tier Target Distribution [Member] | Limited Partner [Member]
Partners' capital account, distributions, allocation percentage	75.40%
Third Tier Target Distribution [Member] | General Partner [Member]
Partners' capital account, distributions, allocation percentage	24.60%
Third Tier Target Distribution [Member] | Limited and General Partners [Member]
Target quarterly distribution	$ 0.1825
Fourth Tier Additional Cash Distribution [Member] | Limited Partner [Member]
Partners' capital account, distributions, allocation percentage	50.40%
Fourth Tier Additional Cash Distribution [Member] | General Partner [Member]
Partners' capital account, distributions, allocation percentage	49.60%

PARTNERS' CAPITAL AND DISTRIB_5

PARTNERS' CAPITAL AND DISTRIBUTIONS Cash Distributions Paid on Preferred Units (Details) - Preferred Units [Member] - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Preferred and General Partners [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Cash Distributions Paid		$ 25,523	$ 25,534	$ 22,837
Distribution Made to Limited Partner, Cash Distributions Declared	$ 6,400
Preferred Partner [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Distributions Declared, Per Unit	$ 0.17875
Distribution Made to Limited Partner, Cash Distributions Paid		25,115	25,115	22,449
Distribution Made to Limited Partner, Cash Distributions Declared	$ 6,300
General Partner [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Cash Distributions Paid		$ 408	$ 420	$ 388
Distribution Made to Limited Partner, Cash Distributions Declared	$ 100

PARTNERS' CAPITAL AND DISTRIB_6

PARTNERS' CAPITAL AND DISTRIBUTIONS Cash Distributions Paid on Common Units (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Limited, General Partner, Phantom Share and Restricted Units [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Cash Distributions Paid		$ 19,213	$ 23,629	$ 21,900
Common Units [Member] | Limited, General Partner, Phantom Share and Restricted Units [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Cash Distributions Declared	$ 3,400
Common Units [Member] | Limited Partner [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Distributions Declared, Per Unit	$ 0.0800
Distribution Made to Limited Partner, Cash Distributions Paid		18,154	22,147	20,509
Distribution Made to Limited Partner, Cash Distributions Declared	$ 3,300
Common Units [Member] | General Partner [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Cash Distributions Paid		626	994	933
Distribution Made to Limited Partner, Cash Distributions Declared	100
Common Units [Member] | Phantom Share Units and Restricted Units [Member]
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Cash Distributions Paid		$ 433	$ 488	$ 458
Distribution Made to Limited Partner, Cash Distributions Declared	$ 100

MAJOR CUSTOMERS AND CONCENTRA_2

MAJOR CUSTOMERS AND CONCENTRATION OF CREDIT RISK (Details) - Customer Concentration Risk [Member]	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Minimum [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	10.00%
All Segments [Member] | Sales Revenue, Net [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	10.00%	12.00%	13.00%
Concentration Risk Number of Customers in Major Customer Group	1	1	1
Crude Oil Pipeline Services [Member] | Sales Revenue, Net [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	15.00%
Concentration Risk Number of Customers in Major Customer Group	2
Ergon Asphalt & Emulsions, Inc. [Member] | Asphalt Terminalling Services [Member] | Sales Revenue, Net [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	13.00%	31.00%	13.00%

RELATED PARTY TRANSACTIONS (Det

RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Oct. 05, 2016
Related Party Transaction [Line Items]
Accrued crude oil purchases to related parties	$ 10,219				$ 0				$ 10,219	$ 0
Related-party revenue									22,131	56,688	$ 30,211
Revenues	123,524	$ 133,158	$ 83,493	$ 44,660	44,248	$ 47,474	$ 43,877	$ 46,340	384,835	181,939	177,394
Receivables from related parties	1,043				3,070				1,043	3,070
Cost of product sales from related party									102,469	0	0
Ergon [Member]
Related Party Transaction [Line Items]
Related-party revenue									48,500	56,400	11,000
Receivables from related parties	1,000				$ 3,100				1,000	3,100
Vitol [Member]
Related Party Transaction [Line Items]
Related-party revenue											17,900
Advantage Pipeline, L.L.C. [Member]
Related Party Transaction [Line Items]
Related-party revenue										300	1,300
Ergon [Member]
Related Party Transaction [Line Items]
Revenues											22,200
Blueknight GP Holding, LLC [Member]
Related Party Transaction [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired												100.00%
Crude Oil Pipeline Services [Member]
Related Party Transaction [Line Items]
Related-party revenue									445	310	5,433
Revenues									242,753	20,984	35,063
Cost of product sales from related party									102,469	$ 0	$ 0
Crude Oil Purchase Agreement [Member] | Ergon [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Purchases from Related Party									108,800
Accrued crude oil purchases to related parties	$ 10,200								$ 10,200

RELATED PARTY TRANSACTIONS Ergo

RELATED PARTY TRANSACTIONS Ergon Agreements (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018USD ($)Terminalling_And_Storage_Facilities	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2018USD ($)Terminalling_And_Storage_Facilities	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Mar. 08, 2019USD ($)	Jan. 01, 2019Years	Jan. 01, 2017Years	Oct. 05, 2016Years	May 18, 2009Years
Related Party Transaction [Line Items]
Related-party revenue									$ 22,131	$ 56,688	$ 30,211
Revenues	$ 123,524	$ 133,158	$ 83,493	$ 44,660	$ 44,248	$ 47,474	$ 43,877	$ 46,340	384,835	181,939	177,394
Ergon [Member]
Related Party Transaction [Line Items]
Related-party revenue									48,500	56,400	11,000
Ergon 2017 Lubbock and Saginaw Storage and Handling Agreement [Member] [Member] | Ergon [Member]
Related Party Transaction [Line Items]
Initial term (in years) | Years														6
Related-party revenue									$ 6,700	12,900
Ergon Storage and Handling Agreement [Member] | Ergon [Member]
Related Party Transaction [Line Items]
Initial term (in years) | Years															7
Number Of Asphalt Terminalling And Storage Facilities | Terminalling_And_Storage_Facilities	9								9
Related-party revenue									$ 24,800	26,400	6,200
Ergon Fontana and Las Vegas Throughput and Handling Agreement [Member] | Ergon [Member]
Related Party Transaction [Line Items]
Initial term (in years) | Years													5
Number Of Asphalt Terminalling And Storage Facilities | Terminalling_And_Storage_Facilities	2								2
Related-party revenue									$ 6,600	6,200	1,500
Ergon Master Facilities Lease Agreement [Member] | Ergon [Member]
Related Party Transaction [Line Items]
Initial term (in years) | Years																2
Number Of Asphalt Terminalling And Storage Facilities | Terminalling_And_Storage_Facilities	8								8
Related-party revenue									$ 5,300	5,200	1,800
Ergon Operating Lease Agreement [Member] | Ergon [Member]
Related Party Transaction [Line Items]
Initial term (in years) | Years													5
Number Of Asphalt Terminalling And Storage Facilities													12
Ergon Master Facilities Sublease and Sublicense Agreement [Member] | Ergon [Member]
Related Party Transaction [Line Items]
Initial term (in years) | Years																2
Number Of Asphalt Terminalling And Storage Facilities | Terminalling_And_Storage_Facilities	5								5
Related-party revenue									$ 2,800	$ 3,700	1,000
Ergon [Member]
Related Party Transaction [Line Items]
Revenues											22,200
Ergon [Member] | Ergon Master Facilities Lease Agreement [Member]
Related Party Transaction [Line Items]
Revenues											9,200
Ergon [Member] | Ergon Master Facilities Sublease and Sublicense Agreement [Member]
Related Party Transaction [Line Items]
Revenues											$ 3,600
Subsequent Event [Member] | Ergon [Member]
Related Party Transaction [Line Items]
Customer Advances, Current												$ 15,000

RELATED PARTY TRANSACTIONS (Vit

RELATED PARTY TRANSACTIONS (Vitol Agreements) (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018USD ($)bbl	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)bbl	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2018USD ($)bbl	Dec. 31, 2017USD ($)bbl	Dec. 31, 2016USD ($)bbl
Related Party Transaction [Line Items]
Related-party revenue									$ 22,131	$ 56,688	$ 30,211
Receivables from related parties, net of allowance for doubtful accounts of $0 at both dates	$ 1,043				$ 3,070				1,043	3,070
Revenues	$ 123,524	$ 133,158	$ 83,493	$ 44,660	$ 44,248	$ 47,474	$ 43,877	$ 46,340	$ 384,835	181,939	177,394
Vitol [Member]
Related Party Transaction [Line Items]
Related-party revenue											$ 17,900
Vitol [Member] | Vitol Storage Agreements [Member]
Related Party Transaction [Line Items]
Related-party revenue										$ 7,500
Barrels of storage capacity of crude oil storage tanks dedicated to related party (in barrels) | bbl											2,215,000
Vitol [Member] | Vitol Storage Agreements [Member]
Related Party Transaction [Line Items]
Barrels of storage capacity of crude oil storage tanks dedicated to related party (in barrels) | bbl					2,000,000					2,000,000
Revenues											$ 9,600
Vitol Storage Agreements [Member] | Vitol [Member]
Related Party Transaction [Line Items]
Barrels of storage capacity of crude oil storage tanks dedicated to related party (in barrels) | bbl	2,215,000								2,215,000

RELATED PARTY TRANSACTIONS Cima

RELATED PARTY TRANSACTIONS Cimarron Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Related Party Transaction [Line Items]
Other Asset Impairment Charges	$ 10,019	$ 0	$ 0
Equity Method Investment, Ownership Percentage	50.00%
Payments to Acquire Property, Plant, and Equipment	$ 34,400	18,715	19,995
Fixed asset impairment charge	42,860	$ 1,293	$ 25,761
Cimarron Express [Member] | Ergon [Member]
Related Party Transaction [Line Items]
Other Asset Impairment Charges	$ 10,019
Devco Purchase Agreement [Member] | Ergon [Member]
Related Party Transaction [Line Items]
Joint Venture Purchase Option	100.00%
Ergon [Member] | Cimarron Express [Member]
Related Party Transaction [Line Items]
Other Asset Impairment Charges	$ 10,000
Payments to Acquire Equity Method Investments	17,600
Cimarron Express [Member]
Related Party Transaction [Line Items]
Payments to Acquire Property, Plant, and Equipment	31,000
Cash	1,900
Fixed asset impairment charge	$ 21,000
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								12 Months Ended
	Jan. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016	Oct. 31, 2016	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based incentive compensation expense (in dollars)									$ 1,845	$ 1,451	$ 2,087
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
Equity-based incentive compensation expense (in dollars)									$ 2,200	$ 2,200	$ 2,500
Number of Units [Roll Forward]
Number of Units, Nonvested, Beginning balance	998,219								923,551
Number of Units, Granted									503,295
Number of Units, Vested									311,927
Number of Units, Forfeited									116,700
Number of Units, Nonvested, Ending balance		998,219		923,551					998,219	923,551
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Nonvested, Beginning balance (in dollars per unit)	$ 5.88								$ 6.29
Weighted Average Grant Date Fair Value, Granted (in dollars per unit)									4.45
Weighted Average Grant Date Fair Value, Vested (in dollars per unit)									6.71
Weighted Average Grant Date Fair Value, Forfeited (in dollars per unit)									5.44
Weighted Average Grant Date Fair Value, Nonvested, Ending balance (in dollars per unit)		$ 5.88		$ 6.29					$ 5.88	$ 6.29
Blueknight Energy Partners G.P., L.L.C. Long-Term Incentive Plan [Member] | Phantom share units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized estimated compensation cost (in dollars)		$ 1,900							$ 1,900
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]
Number of Units, 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		$ 6.85
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]
Number of Units, 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		$ 6.85
January 2018 Vesting [Member] | Blueknight Energy Partners G.P., L.L.C. Long-Term Incentive Plan [Member] | Phantom share units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Value of award grants (in dollars)								$ 1,985
Number of Units [Roll Forward]
Number of Units, Granted								416,131
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Granted (in dollars per unit)								$ 4.77
January 2019 Vesting [Member] | Blueknight Energy Partners G.P., L.L.C. Long-Term Incentive Plan [Member] | Phantom share units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Value of award grants (in dollars)					$ 2,312		$ 58
Number of Units [Roll Forward]
Number of Units, Granted					323,339		9,960
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Granted (in dollars per unit)					$ 7.15		$ 5.85
January 2020 Vesting [Member] | Blueknight Energy Partners G.P., L.L.C. Long-Term Incentive Plan [Member] | Phantom share units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Value of award grants (in dollars)			$ 1,891
Number of Units [Roll Forward]
Number of Units, Granted			396,536
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Granted (in dollars per unit)			$ 4.77
Subsequent Event [Member] | January 2018 Vesting [Member] | Blueknight Energy Partners G.P., L.L.C. Long-Term Incentive Plan [Member] | Phantom share units (PSUs) [Member]
Number of Units [Roll Forward]
Number of Units, Vested	302,786

EMPLOYEE BENEFIT PLAN (Details)

EMPLOYEE BENEFIT PLAN (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Contribution Plan Disclosure [Line Items]
Employee Stock Ownership Plan (ESOP), Shares in ESOP	1,000,000
Employee Stock Ownership Plan (ESOP), Compensation Expense	$ 100,000	$ 76,785.44	$ 100,000
Defined Contribution Pension [Member]
Defined Contribution Plan Disclosure [Line Items]
Employer discretionary contribution amount	1,200,000	1,200,000	1,200,000
Deferred Profit Sharing [Member]
Defined Contribution Plan Disclosure [Line Items]
Employer discretionary contribution amount	$ 200,000	$ 800,000	$ 800,000

PROFITS INTEREST OF BLUEKNIGH_2

PROFITS INTEREST OF BLUEKNIGHT GP HOLDING, LLC (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
Chief Executive Officer [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Chief Executive Officer Non Voting Economic Interest In Company, Amount Recognized During Period	$ 0.9

COMMITMENTS AND CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Operating Leases, Rent Expense	$ 5	$ 6.2	$ 6.5

COMMITMENTS AND CONTINGENCIES O

COMMITMENTS AND CONTINGENCIES Operating Leases (Details) $ in Thousands	Dec. 31, 2018USD ($)
For the twelve months ending:
December 31, 2019	$ 2,862
December 31, 2020	1,904
December 31, 2021	1,242
December 31, 2022	640
December 31, 2023	548
Thereafter	1,259
Total future minimum lease payments	$ 8,455

ENVIRONMENTAL REMEDIATION (Deta

ENVIRONMENTAL REMEDIATION (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Accrual for Environmental Loss Contingencies Disclosure [Abstract]
Accrual for Environmental Loss Contingencies	$ 0.2	$ 0.1

FAIR VALUE MEASUREMENTS Fair _2

FAIR VALUE MEASUREMENTS Fair Value Measurement (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap assets	$ 44	$ 68
Total swap assets	44	68
Interest rate swap liabilities	0	225
Total swap liabilities		225
Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap assets	0	0
Total swap assets	0	0
Interest rate swap liabilities		0
Total swap liabilities		0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap assets	44	68
Total swap assets	44	68
Interest rate swap liabilities		225
Total swap liabilities		225
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap assets	0	0
Total swap assets	$ 0	0
Interest rate swap liabilities		0
Total swap liabilities		$ 0

OPERATING SEGMENTS (Details)

OPERATING SEGMENTS (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018USD ($)StatesTerminalling_And_Storage_Facilities	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2018USD ($)Operating-segmentsStatesTerminalling_And_Storage_Facilities	Dec. 31, 2018USD ($)StatesTerminalling_And_Storage_Facilities	Dec. 31, 2018USD ($)StatesTerminalling_And_Storage_Facilities	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Segment Reporting Information [Line Items]
Number of Operating Segments									4		4
Service revenue:
Third-party revenue										$ 58,756		$ 113,772	$ 126,215
Related-party revenue										22,131		56,688	30,211
Third-party revenue										42,067		0	0
Related-party revenue										25,961		0	0
Product sales revenue:
Third-party revenue										235,438		11,479	20,968
Total revenue for reportable segments	$ 123,524	$ 133,158	$ 83,493	$ 44,660	$ 44,248	$ 47,474	$ 43,877	$ 46,340		384,835		181,939	177,394
Cost of product sales										126,776		8,807	14,130
Cost of product sales from related party										102,469		0	0
Operating margin (excluding depreciation and amortization)										71,059		80,466	82,993
Total assets (end of period)	$ 323,304				340,869				$ 323,304	323,304	$ 323,304	340,869
Reconciles segment operating margin (excluding depreciation and amortization) to income before income taxes
Operating margin (excluding depreciation and amortization)										71,059		80,466	82,993
Depreciation and amortization										(29,359)		(31,139)	(30,820)
General and administrative expenses										(15,995)		(17,112)	(20,029)
Asset impairment expense										(53,068)		(2,400)	(25,761)
Gain (loss) on sale of assets										149		(975)	108
Equity earnings in unconsolidated affiliate										0		61	1,483
Equity Method Investment, Realized Gain (Loss) on Disposal										(2,225)		(5,337)	0
Interest expense										16,860		14,027	12,554
Income (loss) before income taxes										$ (41,849)		20,211	(4,580)
Asphalt Terminalling Services [Member]
Segment Reporting Information [Line Items]
Number Of Asphalt Terminalling And Storage Facilities | Terminalling_And_Storage_Facilities	53								53	53	53
Service revenue:
Third-party revenue										$ 26,108		57,486	75,655
Related-party revenue										21,686		56,378	11,762
Third-party revenue										41,319		0	0
Related-party revenue										25,961		0	0
Product sales revenue:
Third-party revenue										482		0	0
Total revenue for reportable segments										115,556		113,864	87,417
Operating expense, excluding depreciation and amortization										49,229		49,241	30,648
Operating margin (excluding depreciation and amortization)										66,327		64,623	56,769
Additions to long-lived assets										30,068		22,046	148,622
Total assets (end of period)	$ 138,245				146,966				$ 138,245	138,245	$ 138,245	146,966	141,280
Reconciles segment operating margin (excluding depreciation and amortization) to income before income taxes
Operating margin (excluding depreciation and amortization)										$ 66,327		64,623	56,769
Number Of States Asphalt Terminalling Facilities are Located | States	26								26	26	26
Crude Oil Terminalling Services [Member]
Service revenue:
Third-party revenue										$ 11,928		22,177	16,387
Related-party revenue										0		0	7,858
Intersegment revenue										704		0	0
Third-party revenue										45		0	0
Product sales revenue:
Total revenue for reportable segments										12,677		22,177	24,245
Operating expense, excluding depreciation and amortization										3,899		4,200	4,197
Operating margin (excluding depreciation and amortization)										8,778		17,977	20,048
Additions to long-lived assets										3,394		2,194	2,126
Total assets (end of period)	$ 68,480				69,149				$ 68,480	68,480	$ 68,480	69,149	71,689
Reconciles segment operating margin (excluding depreciation and amortization) to income before income taxes
Operating margin (excluding depreciation and amortization)										8,778		17,977	20,048
Crude Oil Pipeline Services [Member]
Service revenue:
Third-party revenue										6,396		9,580	8,662
Related-party revenue										445		310	5,433
Third-party revenue										484		0	0
Product sales revenue:
Third-party revenue										235,428		11,094	20,968
Total revenue for reportable segments										242,753		20,984	35,063
Operating expense, excluding depreciation and amortization										11,828		13,310	15,270
Intersegment operating expense										5,284		417	890
Cost of product sales										126,776		8,807	14,130
Cost of product sales from related party										102,469		0	0
Intersegment cost of product sales										0		150	426
Operating margin (excluding depreciation and amortization)										(3,604)		(1,700)	4,347
Additions to long-lived assets										19,654		2,934	8,250
Total assets (end of period)	112,429				117,749				112,429	112,429	112,429	117,749	150,043
Reconciles segment operating margin (excluding depreciation and amortization) to income before income taxes
Operating margin (excluding depreciation and amortization)										(3,604)		(1,700)	4,347
Crude Oil Trucking Services [Member]
Service revenue:
Third-party revenue										14,324		24,529	25,511
Related-party revenue										0		0	5,158
Intersegment revenue										4,580		417	890
Third-party revenue										219		0	0
Product sales revenue:
Third-party revenue										10		385	0
Intersegment revenue										0		150	426
Total revenue for reportable segments										19,133		25,481	31,985
Operating expense, excluding depreciation and amortization										19,575		25,915	30,156
Operating margin (excluding depreciation and amortization)										(442)		(434)	1,829
Additions to long-lived assets										3,243		1,701	2,558
Total assets (end of period)	$ 4,150				$ 7,005				$ 4,150	4,150	$ 4,150	7,005	12,651
Reconciles segment operating margin (excluding depreciation and amortization) to income before income taxes
Operating margin (excluding depreciation and amortization)										(442)		(434)	1,829
Intersegment Eliminations [Member]
Service revenue:
Intersegment revenue										(5,284)		(567)	(1,316)
Product sales revenue:
Total revenue for reportable segments										$ 390,119		$ 182,506	$ 178,710

INCOME TAXES (Details)

INCOME TAXES (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal statutory income tax rate (as a percent)	21.00%		35.00%
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount		$ 300
Percent of Qualifying Income, minimum	90.00%
Difference in bases of property, plant and equipment	$ 273
Deferred tax asset	273
Less: valuation allowance	(273)
Net deferred tax asset	$ 0

RECENTLY ISSUED ACCOUNTING ST_2

RECENTLY ISSUED ACCOUNTING STANDARDS Effect of Implementation (Details) - Accounting Standards Update 2016-02 [Member] $ in Millions	Jan. 01, 2019USD ($)
Finance Lease, Liability	$ 0.6
Subsequent Event [Member]
Operating Lease, Liability	11.9
Operating Lease, Right-of-Use Asset	11.7
Finance Lease, Right-of-Use Asset	$ 0.6

QUARTERLY FINANCIAL DATA (Detai

QUARTERLY FINANCIAL DATA (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Data [Abstract]
Revenues	$ 123,524	$ 133,158	$ 83,493	$ 44,660	$ 44,248	$ 47,474	$ 43,877	$ 46,340	$ 384,835	$ 181,939	$ 177,394
Operating income (loss)	(46,522)	6,663	6,830	5,815	3,559	12,219	6,505	6,557	(27,214)	28,840	6,491
Net income (loss)	$ (50,682)	$ 2,408	$ 1,785	$ 4,442	$ 361	$ 9,771	$ 6,371	$ 3,542	$ (42,047)	$ 20,045	$ (4,840)
Basic and diluted net loss per common unit	$ (1.36)	$ (0.09)	$ (0.11)	$ (0.05)	$ (0.15)	$ 0.08	$ 0	$ (0.08)	$ (1.61)	$ (0.15)	$ (0.87)