Noble Midstream Partners (NBLX) 10-K 12 Feb 21 2020 FY Annual report Financial data

Cover Page

Cover Page - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Jan. 29, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-37640
Entity Registrant Name	NOBLE MIDSTREAM PARTNERS LP
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	47-3011449
Entity Address, Address Line One	1001 Noble Energy Way
Entity Address, City	Houston,
Entity Address, State	TX
Entity Address, Postal Zip Code	77070
City Area Code	(281)
Local Phone Number	872-3100
Title of each class	Common Units, Representing Limited Partner Interests
Trading Symbol(s)	NBLX
Name of each exchange on which registered	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 285.2
Entity Common Stock, Shares Outstanding		90,347,145
Documents Incorporated by Reference	None
Entity Central Index Key	0001647513
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current Assets
Cash and Cash Equivalents	$ 16,332	$ 12,676
Accounts Receivable — Affiliate	55,011	42,428
Accounts Receivable — Third Party	45,615	44,093
Other Current Assets	8,093	8,730
Total Current Assets	125,051	107,927
Property, Plant and Equipment
Total Property, Plant and Equipment, Gross	2,074,790	2,006,995
Less: Accumulated Depreciation and Amortization	(315,441)	(244,038)
Total Property, Plant and Equipment, Net	1,759,349	1,762,957
Investments	904,955	660,778
Intangible Assets, Net	245,510	277,900
Goodwill	0	109,734
Other Noncurrent Assets	2,331	6,786
Total Assets	3,037,196	2,926,082
Current Liabilities
Accounts Payable — Affiliate	3,713	8,155
Accounts Payable — Trade	65,723	107,705
Current Portion of Debt	501,856	0
Other Current Liabilities	10,323	11,680
Total Current Liabilities	581,615	127,540
Long-Term Liabilities
Long-Term Debt	1,109,652	1,495,679
Asset Retirement Obligations	41,572	37,842
Other Long-Term Liabilities	4,006	4,160
Total Liabilities	1,736,845	1,665,221
Mezzanine Equity
Redeemable Noncontrolling Interest, Net	119,658	106,005
Equity
Common Units (90,174 and 90,136 units outstanding, respectively)	823,470	813,999
Noncontrolling Interests	357,223	340,857
Total Equity	1,180,693	1,154,856
Total Liabilities, Mezzanine Equity and Equity	$ 3,037,196	$ 2,926,082

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - shares	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Units outstanding (in shares)	90,174	90,136

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues
Midstream Services — Affiliate	$ 389,192	$ 417,835	$ 338,747
Total Revenues	764,625	703,801	558,735
Costs and Expenses
Cost of Crude Oil Sales	270,678	181,390	136,368
Direct Operating	92,387	116,675	95,852
Depreciation and Amortization	105,697	96,981	79,568
General and Administrative	24,721	25,777	25,910
Goodwill Impairment	109,734	0	0
Other Operating (Income) Expense	4,698	(488)	2,159
Total Operating Expenses	607,915	420,335	339,857
Operating Income	156,710	283,466	218,878
Other Expense (Income)
Interest Expense, Net of Amount Capitalized	26,570	16,236	10,447
Investment Loss (Income)	34,891	17,748	(16,289)
Total Other Expense (Income)	61,461	33,984	(5,842)
Income Before Income Taxes	95,249	249,482	224,720
Tax Provision	383	4,015	8,001
Net Income	94,866	245,467	216,719
Less: Net Income Prior to the Drop-Down and Simplification	0	12,929	27,843
Net Income Subsequent to the Drop-Down and Simplification	94,866	232,538	188,876
Less: Net (Loss) Income Attributable to Noncontrolling Interests	(39,165)	72,542	26,142
Net Income Attributable to Noble Midstream Partners LP	134,031	159,996	162,734
Less: Net Income Attributable to Incentive Distribution Rights	0	13,967	5,836
Net Income Attributable to Limited Partners	134,031	146,029	156,898
Common Units
Other Expense (Income)
Net Income Attributable to Limited Partners	$ 134,031	$ 123,662	$ 93,875
Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic
Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic (in dollars per share)	$ 1.49	$ 3.09	$ 3.96
Net Income Attributable to Limited Partners Per Limited Partner Unit — Diluted
Net Income Attributable to Limited Partners Per Limited Partner Unit — Diluted (in dollars per share)	$ 1.49	$ 3.08	$ 3.96
Weighted Average Limited Partner Units Outstanding — Basic
Weighted Average Limited Partner Units Outstanding - Basic (in shares)	90,165	40,083	23,686
Weighted Average Limited Partner Units Outstanding — Diluted
Weighted Average Limited Partner Units Outstanding — Diluted (in shares)	90,167	40,105	23,701
Subordinated Units
Other Expense (Income)
Net Income Attributable to Limited Partners	$ 0	$ 22,367	$ 63,023
Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic
Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic (in dollars per share)	$ 0	$ 3.86	$ 3.96
Net Income Attributable to Limited Partners Per Limited Partner Unit — Diluted
Net Income Attributable to Limited Partners Per Limited Partner Unit — Diluted (in dollars per share)	$ 0	$ 3.86	$ 3.96
Weighted Average Limited Partner Units Outstanding — Basic
Weighted Average Limited Partner Units Outstanding - Basic (in shares)	0	5,795	15,903
Weighted Average Limited Partner Units Outstanding — Diluted
Weighted Average Limited Partner Units Outstanding — Diluted (in shares)	0	5,795	15,903
Midstream Services — Third Party
Revenues
Services and Sales Revenues - Third Party	$ 94,228	$ 96,194	$ 78,498
Crude Oil Sales — Third Party
Revenues
Services and Sales Revenues - Third Party	$ 281,205	$ 189,772	$ 141,490

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash Flows From Operating Activities
Net Income		$ 94,866	$ 245,467	$ 216,719
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Depreciation and Amortization		105,697	96,981	79,568
Income Taxes		0	3,848	7,780
Goodwill Impairment		109,734	0	0
Loss (Income) from Equity Method Investees		37,726	22,435	(11,880)
Distributions from Equity Method Investees		36,973	10,135	9,219
Unit-Based Compensation		2,195	1,052	1,392
Other Adjustments for Noncash Items Included in Income		5,582	1,060	4,209
Changes in Operating Assets and Liabilities, Net of Assets Acquired and Liabilities Assumed
Increase in Accounts Receivable		(14,105)	(24,126)	(13,863)
Increase (Decrease) in Accounts Payable		339	28,755	(22,101)
Other Operating Assets and Liabilities, Net		(2,378)	(464)	2,644
Net Cash Provided by Operating Activities		376,629	385,143	273,687
Cash Flows From Investing Activities
Additions to Property, Plant and Equipment		(113,388)	(262,342)	(619,517)
Black Diamond Acquisition, Net of Cash Acquired		0	0	(649,868)
Additions to Investments		(317,229)	(611,325)	(426)
Distributions from Cost Method Investee and Other		3,063	1,074	1,323
Net Cash Used in Investing Activities		(427,554)	(872,593)	(1,268,488)
Cash Flows From Financing Activities
Distributions to Noncontrolling Interests and Parent		(30,187)	(57,071)	(38,056)
Contributions from Noncontrolling Interests		85,718	55,481	605,864
Borrowings Under Revolving Credit Facility		450,000	1,290,000	777,000
Repayment of Revolving Credit Facility		(335,000)	(755,000)	(802,000)
Proceeds from Term Loan Credit Facilities		0	400,000	500,000
Proceeds from Preferred Equity, Net of Issuance Costs		0	97,198	0
Proceeds from Preferred Equity, Net of Issuance Costs		0	242,770	0
Distribution to Noble for Common Control Transactions		0	(670,000)	0
Distributions to Unitholders		(112,880)	(115,935)	(86,841)
Other		(3,120)	(2,979)	(3,049)
Net Cash Provided by Financing Activities		54,531	484,464	952,918
Increase (Decrease) in Cash, Cash Equivalents, and Restricted Cash		3,606	(2,986)	(41,883)
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	[1]	12,726	15,712	57,595
Cash, Cash Equivalents, and Restricted Cash at End of Period	[1]	$ 16,332	$ 12,726	$ 15,712
[1]	See Note 2. Summary of Significant Accounting Policies and Basis of Presentation for our reconciliation of total cash.

Consolidated Statements of Chan

Consolidated Statements of Changes in Equity - USD ($) $ in Thousands		Total	Parent Net Investment	Noncontrolling Interests	Limited PartnerCommon Units	Limited PartnerSubordinated UnitsNoble	General Partner
Beginning Balance at Dec. 31, 2017		$ 786,659	$ 170,429	$ 141,230	$ 642,616	$ (168,136)	$ 520
Increase (Decrease) in Partners' Capital
Net Income		216,719	27,843	26,142	93,875	63,023	5,836
Contributions from Noncontrolling Interests and Parent		606,713	849	605,864
Distributions to Noncontrolling Interests and Parent		(38,056)	(28,799)	(9,257)
Distributions to Unitholders		(86,841)			(49,610)	(33,296)	(3,935)
Black Diamond Equity Ownership Promote Vesting	[1]	0		(19,826)	11,624	8,202
Other		1,361			1,361
Ending Balance at Dec. 31, 2018		1,486,555	170,322	744,153	699,866	(130,207)	2,421
Increase (Decrease) in Partners' Capital
Net Income		245,467	12,929	72,542	123,662	22,367	13,967
Contributions from Noncontrolling Interests and Parent		55,481		55,481
Distributions to Noncontrolling Interests and Parent	[2]	(80,992)	(54,889)	(26,103)
Distributions to Unitholders		(115,935)			(80,480)	(19,067)	$ (16,388)
Black Diamond Equity Ownership Promote Vesting	[1]	0		(20,391)	17,645	2,746
Conversion of Subordinated Units to Common Units	[3]	0			(124,161)	$ 124,161
Preferred Equity Accretion		(9,440)			(9,440)
Net Proceeds from Offerings		242,770			242,770
Distribution to Noble for Drop-Down and Simplification Transaction	[4]	(670,000)			(670,000)
Asset Transfers for Drop-Down and Simplification Transaction		0	(128,362)	(484,825)	613,187
Other		950			950
Ending Balance at Dec. 31, 2019		1,154,856	0	340,857	813,999
Increase (Decrease) in Partners' Capital
Net Income		94,866		(39,165)	134,031
Contributions from Noncontrolling Interests and Parent		85,718		85,718
Distributions to Noncontrolling Interests and Parent		(30,187)		(30,187)
Distributions to Unitholders		(112,880)			(112,880)
Preferred Equity Accretion		(13,653)			(13,653)
Other		1,973			1,973
Ending Balance at Dec. 31, 2020		$ 1,180,693	$ 0	$ 357,223	$ 823,470
[1]	See N ote for further discussion of the Black Diamond equity ownership promote vesting.
[2]	Includes the elimination of a deferred tax asset and current tax liability associated with the Drop-Down and Simplification Transaction. See Note
[3]	See Note
[4]	See Note for further discussion of our common control transactions.

Organization and Nature of Oper

Organization and Nature of Operations	12 Months Ended
	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Nature of Operations	Note 1. Organization and Nature of Operations Organization We are a growth-oriented Delaware master limited partnership formed in December 2014 to own, operate, develop and acquire a wide range of domestic midstream infrastructure assets. Our current areas of focus are in the DJ Basin and the Delaware Basin. Chevron Merger In fourth quarter 2020, Chevron completed the acquisition of Noble, the indirect general partner and majority unit holder of the Partnership. As a result, Chevron indirectly wholly owns our General Partner and indirectly holds approximately 62.6% of our limited partner Common Units. Non-Binding Proposal from Chevron On February 4, 2021, the board of directors of our General Partner received a non-binding proposal from Chevron Corporation, pursuant to which Chevron would acquire all common units of the Partnership that Chevron and its affiliates do not already own in exchange for a to-be-determined fixed exchange ratio, based on a value of $12.47 per common unit. If approved, the transaction would be effected through a merger of the Partnership with a subsidiary of Chevron. The transaction, as proposed, is subject to a number of contingencies, including the approval of the conflicts committee, the approval by holders of a majority of the outstanding common units of the Partnership and the satisfaction of any conditions to the consummation of a transaction set forth in any definitive agreement concerning the transaction. There can be no assurance that definitive documentation will be executed or that any transaction will materialize. Partnership Assets Our assets consist of ownership interests in certain companies which serve specific areas and integrated IDP areas and consist of the following: Company Areas Served NBLX Dedicated Service NBLX Ownership Noncontrolling Interest (1) Colorado River LLC Crude Oil Gathering 100% N/A San Juan River LLC East Pony IDP (DJ Basin) Water Services 100% N/A Green River DevCo LLC Mustang IDP (DJ Basin) Crude Oil Gathering 100% N/A Laramie River LLC Greeley Crescent IDP (DJ Basin) Crude Oil Gathering 100% N/A Black Diamond Dedication Area (DJ Basin) (2) Crude Oil Gathering 54.4% 45.6% Gunnison River DevCo LP Bronco IDP (DJ Basin) (3) Crude Oil Gathering 5% 95% Blanco River LLC Delaware Basin Crude Oil Gathering 100% N/A Trinity River DevCo LLC (4) Delaware Basin Crude Oil Transmission 100% N/A Dos Rios DevCo LLC (5) Delaware Basin Crude Oil Transmission 100% N/A NBL Midstream Holdings LLC East Pony IDP (DJ Basin) Natural Gas Gathering 100% N/A Delaware Basin Crude Oil Gathering 100% N/A (1) The noncontrolling interest represents Noble’s retained ownership interest in the Gunnison River DevCo LP. The noncontrolling interest in Black Diamond represents Greenfield Member’s interest in Black Diamond. (2) Our ownership interest in Saddlehorn is owned through a wholly-owned subsidiary of Black Diamond. See Note . (3) The Bronco IDP area is a future development area. We currently have no midstream infrastructure assets in the Bronco IDP area. (4) Our interest in Advantage is owned through Trinity River DevCo LLC. (5) Our ownership interests in Delaware Crossing, EPIC Crude, EPIC Y-Grade and EPIC Propane are owned through wholly-owned subsidiaries of Dos Rios DevCo LLC. See Note . Nature of Operations We operate and own interests in the following assets: • crude oil gathering systems; • natural gas gathering and processing systems and compression units; • crude oil treating facilities; • produced water collection, gathering, and cleaning systems; • fresh water storage and delivery systems; and • investments in midstream entities that provide transportation services. We generate revenues primarily by charging fees on a per unit basis for gathering crude oil, gathering and processing natural gas, delivering and storing fresh water and collecting, cleaning and disposing of produced water. Additionally, we purchase crude oil from producers and sell crude oil to customers at various delivery points. We have entered into multiple fee-based commercial agreements with Noble, each with an initial term of 15 years, to provide these services which are critical to Noble’s upstream operations. Our agreements include substantial acreage dedications. See Note .

Summary of Significant Accounti

Summary of Significant Accounting Policies and Basis of Presentation	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies and Basis of Presentation	Note 2. Summary of Significant Accounting Policies and Basis of Presentation Basis of Presentation and Consolidation Our consolidated financial statements were prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”). All intercompany balances and transactions have been eliminated upon consolidation. The Partnership has no items of other comprehensive income or loss; therefore, its net income is identical to its comprehensive income. Variable Interest Entities Our consolidated financial statements include the accounts of Black Diamond, which we control. We have determined that the partners with equity at risk in Black Diamond lack the authority, through voting rights or similar rights, to direct the activities that most significantly impact their economic performance. Therefore, Black Diamond is considered a VIE. Through our majority representation on the Black Diamond board of directors as well as our responsibility as operator of the Black Diamond system, we have the authority to direct the activities that most significantly affect economic performance and the obligation to absorb losses or the right to receive benefits that could be potentially significant to us. Therefore, we are considered the primary beneficiary and consolidate Black Diamond in our financial statements. All financial statement activity associated with Black Diamond is captured within the Gathering Systems reportable segment. See Note . Drop-Down and Simplification Transaction On November 21, 2019, we closed the Drop-Down and Simplification Transaction with Noble, as described in Note . The Drop-Down and Simplification Transaction represented a transaction between entities under common control. Prior to the acquisition of the remaining limited partner interests in Blanco River DevCo LP, Green River DevCo LP and San Juan River DevCo LP, the interests were reflected as noncontrolling interests in the Partnership’s consolidated financial statements. As we acquired additional interests in already-consolidated entities, the acquisition of these interests did not result in a change in reporting entity, as defined under Financial Accounting Standards Board (“FASB”) Accounting Standards Codification Topic 805, Business Combinations. Therefore, results of operations related to these entities are accounted for on a prospective basis. Conversely, the acquisition of all of the issued and outstanding limited liability company interests of NBL Holdings is characterized as a change in reporting entity, as defined under FASB Accounting Standards Codification Topic 805, Business Combinations , as this entity previously had not been consolidated by us. Therefore, results of operations related to NBL Holdings are accounted for on a retrospective basis. Our financial information was therefore recast to include the historical results of NBL Holdings for all periods presented. The financial statements of NBL Holdings for periods prior to the Drop-Down and Simplification Transaction have been prepared from the separate records maintained by Noble and may not necessarily be indicative of the results of operations had these entities operated on a consolidated basis during those periods. Because a direct ownership relationship did not exist among the Partnership and NBL Holdings prior to the Drop-Down and Simplification Transaction, the net investment in NBL Holdings is shown as Parent Net Investment, in lieu of partners’ equity, in the accompanying Consolidated Statement of Changes in Equity for periods prior to the Drop-Down and Simplification Transaction. Equity Method of Accounting We use the equity method of accounting for investments in entities that we do not control but over which we exert significant influence. For certain entities, we serve as the operator and exert significant influence over the day-to-day operations. For other entities, we do not serve as the operator; however, our voting position on management committees or the board of directors allows us to exert significant influence over decisions regarding capital investments, budgets, turnarounds, maintenance, monetization decisions and other project matters. Under the equity method of accounting, initially we record the investment at our cost. Differences in the cost, or basis, of the investment and the net asset value of the investee will be amortized into earnings over the remaining useful life of the underlying assets. See Note . Cost Method of Accounting We use the cost method of accounting for our White Cliffs Interest as we have virtually no influence over its operations and financial policies. Under the cost method of accounting, we recognize cash distributions from White Cliffs Pipeline L.L.C. as investment income in our consolidated statements of operations to the extent there is net income and record cash distributions in excess of our ratable share of earnings as return of investment. See Note . Redeemable Noncontrolling Interest Our redeemable noncontrolling interest is related to our 2019 preferred equity issuance . We can redeem the preferred equity in whole or in part at any time for cash at a predetermined redemption price. The predetermined redemption price is the greater of (i) an amount necessary to achieve a 12% internal rate of return or (ii) an amount necessary to achieve a 1.375x multiple on invested capital. GIP can request redemption of the preferred equity on or after March 25, 2025. As GIP’s redemption right is outside of our control, the preferred equity is not considered to be a component of equity on the consolidated balance sheet, and is reported as mezzanine equity on the consolidated balance sheet. In addition, because the preferred equity was issued by a subsidiary of the Partnership and is held by a third party, it is considered a redeemable noncontrolling interest. The preferred equity was recorded initially at fair value on the issuance date. Subsequent to issuance, we accrete changes in the redemption value of the preferred equity from the date of issuance to GIP’s earliest redemption date. The preferred equity is perpetual and has a 6.5% annual dividend rate, payable quarterly in cash, with the ability to accrue unpaid dividends during the first two years following the closing. During any quarter in which a dividend is accrued, the accreted value of the preferred equity will be increased by the accrued but unpaid dividend (i.e., a paid-in-kind dividend). See Note . Noncontrolling Interests We present our consolidated financial statements with a noncontrolling interest section representing Noble’s retained ownership in the Gunnison River DevCo LP as well as Greenfield Member’s ownership of Black Diamond. Segment Information Accounting policies for reportable segments are the same as those described in this footnote. Transfers between segments are accounted for at market value. We do not consider interest income and expense or income tax benefit or expense in our evaluation of the performance of reportable segments. See Note . Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires us to make a number of estimates and assumptions relating to the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ significantly from those estimates. Management evaluates estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic and commodity price environment. Cash and Cash Equivalents For purposes of reporting cash flows, cash and cash equivalents include unrestricted cash on hand and investments with original maturities of three months or less at the time of purchase. Accounts Receivable and Allowance for Expected Credit Losses Our accounts receivable result primarily from our midstream gathering services, fresh water services and crude oil sales. The majority of these receivables have payment terms of 30 days or less. At the end of each reporting period, we assess the recoverability of all material receivables using historical data, current market conditions, and reasonable and supportable forecasts of future economic conditions to determine their expected collectibility. The loss given default method is used when, based on management's judgment, an allowance for expected credit losses should be accrued on a material receivable to reflect the net amount expected to be collected. Property, Plant and Equipment Property, plant and equipment primarily consists of crude oil gathering systems, natural gas gathering systems, natural gas plants and compression units, produced water collection, gathering, and cleaning systems, fresh water storage and delivery systems and crude oil treating facilities. Property and equipment is stated at the lower of historical cost less accumulated depreciation, or fair value, if impaired. Capitalized Interest We capitalize construction-related direct labor and incremental costs, such as interest expense. Capitalized interest totaled $5.5 million in 2020, $17.5 million in 2019, and $6.4 million in 2018. Depreciation Depreciation is computed over the asset’s estimated useful life using the straight line method based on estimated useful lives and asset salvage values. Determination of depreciation expense requires judgment regarding the estimated useful lives and salvage values of property, plant and equipment. As circumstances warrant, depreciation estimates are reviewed to determine if any changes in the underlying assumptions are necessary. The weighted average life of our long-lived assets is 29 years. The depreciation of fixed assets recorded under capital lease agreements is included in depreciation and amortization expense. See Note . Impairment of Long-Lived Assets We routinely assess whether impairment indicators arise during any given quarter and have processes in place to ensure that we become aware of such indicators. Impairment indicators include, but are not limited to, sustained decreases in commodity prices, a decline in customer well results and lower throughput forecasts, changes in customer development plans, and/or increases in our construction or operating costs. In the event that impairment indicators exist, we conduct an impairment test. We evaluate our ability to recover the carrying amounts of long-lived assets and determine whether such long-lived assets have been impaired. Impairment exists when the carrying value of an asset exceeds the estimated undiscounted future cash flows expected to result from the use and eventual disposition of the asset. When the carrying amount of a long-lived asset exceeds its estimated undiscounted future cash flows, the carrying amount of the asset is reduced to its estimated fair value. Fair value may be estimated using comparable market data, a discounted cash flow method, or a combination of the two. During 2018, we recorded an asset impairment of $3.5 million related to a damaged gathering system asset. The asset impairment was partially offset by an expected recovery of $2.5 million. The resulting net impairment totaled $1.0 million and is recorded within other operating expense in our consolidated statement of operations. During first quarter 2020, we identified certain impairment indicators including the significant decrease in commodity prices, changes to our customers’ development outlook due to reductions in demand resulting from the COVID-19 pandemic, excess crude oil and natural gas inventories and a decrease in our market capitalization. Due to these impairment indicators, we conducted impairment testing of certain of our assets including property, plant and equipment, equity method investments, customer relationship intangibles and goodwill. With the exception of goodwill, we concluded that the carrying amount of assets were recoverable and no impairment was recorded. Asset Retirement Obligations Asset Retirement Obligations (“AROs”) consist of estimated costs of dismantlement, removal, site reclamation and similar activities associated with our property and equipment. We recognize the fair value of a liability for an ARO in the period in which it is incurred when we have an existing legal obligation associated with the retirement of our infrastructure assets and the obligation can reasonably be estimated. The associated asset retirement cost is capitalized as part of the carrying cost of the infrastructure asset. The recognition of an ARO requires that management make numerous estimates, assumptions and judgments regarding such factors as: the existence of a legal obligation for an ARO; estimated probabilities, amounts and timing of settlements; the credit-adjusted risk-free rate to be used; and inflation rates. In periods subsequent to initial measurement of the ARO, we recognize period-to-period changes in the liability resulting from the passage of time and revisions to either the timing or the amount of the original estimate of undiscounted cash flows. Revisions also result in increases or decreases in the carrying cost of the asset. Increases in the ARO liability due to passage of time impact net income as accretion expense. The related capitalized cost, including revisions thereto, is charged to expense through depreciation and amortization. See Note . With respect to property, plant and equipment associated with the Black Diamond system, it is our practice and current intent to maintain these assets and continue to make improvements as warranted. As a result, we believe that these assets have indeterminate lives for purposes of estimating AROs because dates or ranges of dates upon which we would retire these assets cannot reasonably be estimated at this time; therefore, no AROs have been recorded for these assets as of December 31, 2020 or 2019. Goodwill Our goodwill was assigned to the Black Diamond reporting unit within the Gathering Systems reportable segment. As discussed above, we performed a qualitative assessment and concluded it was more likely than not that the fair value of the Black Diamond reporting unit was less than its carrying value. We then performed a fair value assessment using the income approach. Our estimate of fair value required us to use significant unobservable inputs, representative of a Level 3 fair value measurement, including assumptions for operating and development costs as well as taking into account changes and uncertainties in our customers’ development outlook. Based on these assessments, we concluded that our goodwill was fully impaired and recorded a non-cash charge of $109.7 million in March 2020. See Note for further details on goodwill. Investments We routinely assess our investments for impairment whenever changes in facts and circumstances indicate a loss in value has occurred. When impairment indicators exist, the fair value is estimated and compared to the investment carrying amount. When the carrying amount of an investment exceeds its estimated undiscounted future cash flows, the carrying amount of the investment is reduced to its estimated fair value. Fair value may be estimated using comparable market data, a discounted cash flow method, or a combination of the two. No impairments have been recorded through December 31, 2020. Intangible Assets Our intangible assets are comprised of customer contracts acquired in the Black Diamond Acquisition and recorded under the acquisition method of accounting at their estimated fair values at the date of acquisition. The customer contracts are long-term, fixed-fee contracts for the purchase and sale of crude oil. Amortization is calculated using the straight-line method by customer contract, which reflects the pattern in which the estimated economic benefit is expected to be received over the estimated useful life of the intangible asset. The estimated economic benefit was determined by assessing the life of the assets related to the contracts and relationships, likelihood of renewals, competitive factors, regulatory or legal provisions and maintenance costs. The amortization of intangible assets is included in depreciation and amortization expense in our consolidated statements of operations. Intangible assets with finite useful lives are reviewed for impairment when events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. See Note and Note . Fair Value Measurements Fair value measurements are based on a hierarchy which prioritizes the inputs to valuation techniques used to measure fair value into three levels. The fair value hierarchy is as follows: • Level 1 measurements are fair value measurements which use quoted market prices (unadjusted) in active markets for identical assets or liabilities. • Level 2 measurements are fair value measurements which use inputs, other than quoted prices included within Level 1, which are observable for the asset or liability, either directly or indirectly. • Level 3 measurements are fair value measurements which use unobservable inputs. We measure assets and liabilities requiring fair value presentation and disclose such amounts according to the quality of valuation inputs under the fair value hierarchy. The carrying amounts of our cash and cash equivalents, accounts receivable and accounts payable approximate fair value due to the short-term nature and maturity of the instruments and use Level 1 inputs. Our revolving credit facility and term loan credit facilities are variable-rate, non-public debt. The fair value of our revolving credit facility and term loan credit facilities is equivalent to the carrying amount. The fair value is estimated based on significant other observable inputs. As such, we consider the fair value of these facilities to be a Level 2 measurement on the fair value hierarchy. See Note . The fair value of the intangible assets was calculated using the multi-period excess earnings method under the income approach for the existing customers. This valuation method is based on first forecasting gross profit for the existing customers and then applying expected attrition rates. The operating cash flows were calculated by determining the costs required to generate gross profit from the existing customers. The key assumptions include overall gross profit growth, attrition rate of existing customers over time and the discount rate. As the fair value is based on inputs that are not observable in the market, these represent Level 3 inputs. See Note . Certain assets and liabilities, such as property, plant, and equipment, investments, and other intangible assets, are not required to be measured at fair value on a recurring basis. However, these assets are assessed for impairment, and a resulting impairment would require the asset be recorded at fair value. Loan and Capital Contribution to Equity Method Investee In April 2020 we entered into a loan agreement with EPIC Y-Grade in which we loaned the entity $22.5 million to be used for construction and working capital purposes with a maturity date of December 15, 2023. During July 2020, the loan plus accrued interest was converted to equity and treated as a capital contribution to EPIC Y-Grade. At the time of conversion, the loan plus accrued interest totaled $23.4 million. Transactions with Affiliates Transactions between Noble, its affiliates and us have been identified in the consolidated financial statements as transactions with affiliates. See Note . Unit-Based Compensation Unit-based compensation issued to individuals providing services to us is recorded at grant-date fair value. Expense is recognized on a straight-line basis over the requisite service period (generally the vesting period of the award) in the consolidated statements of operations. See Note . Litigation and Other Contingencies We may become subject to legal proceedings, claims and liabilities that will arise in the ordinary course of business. We will accrue for losses associated with legal claims when such losses are considered probable and the amounts can be reasonably estimated. See Note . Leases In the normal course of business, we enter into lease agreements to support our operations. We lease field equipment as well as water and pipeline transportation assets. Operating Leases Our operating leases consist of field equipment and transportation assets. Our field equipment leases have fixed monthly payments over a minimum term with options to extend the rental period on a month-to-month basis. Our leased transportation assets have variable monthly payments (price per barrel throughput) over a minimum term with the option to extend on a year-to-year basis. Our operating and variable lease expense is recorded in direct operating expense in our consolidated statement of operations and was de minimis for the year ended December 31, 2020. Finance Leases We lease water assets for use in the performance of our fresh water delivery services. The amount of the lease obligation is based on the discounted present value of future minimum lease payments, and therefore does not reflect future cash lease payments. Our finance lease expense is recorded in depreciation and amortization expense in our consolidated statement of operations and was de minimis for the year ended December 31, 2020. Interest expense for our finance lease is recorded in interest expense in our consolidated statement of operations and was de minimis for the year ended December 31, 2020. Short-Term Leases Leases with an initial term of 12 months or less are not recorded on the balance sheet; we recognize lease expense for these leases on a straight-line basis over the lease term. Short-term lease expense is recorded in direct operating expense in our consolidated statement of operations and was de minimis for the year ended December 31, 2020. Supplemental Cash Flow Information We accrued $12.5 million, $56.6 million and $72.6 million related to midstream capital expenditures as of December 31, 2020, 2019 and 2018, respectively. Cash interest paid totaled $31.3 million, $33.0 million and $16.3 million for the years ended December 31, 2020, 2019 and 2018, respectively. During 2019, in connection with the closing of the Drop-Down and Simplification Transaction, we eliminated a deferred tax asset and current tax liability associated with NBL Holdings. The deferred tax asset and current tax liability totaled approximately $26.0 million and $2.9 million, respectively, and represented a non-cash activity. Reconciliation of Total Cash We define total cash as cash, cash equivalents and restricted cash. The following table provides a reconciliation of total cash: Year Ended December 31, (in thousands) 2020 2019 2018 Cash and Cash Equivalents at Beginning of Period $ 12,676 $ 14,761 $ 20,090 Restricted Cash at Beginning of Period (1) (2) 50 951 37,505 Cash, Cash Equivalents, and Restricted Cash at Beginning of Period $ 12,726 $ 15,712 $ 57,595 Cash and Cash Equivalents at End of Period $ 16,332 $ 12,676 $ 14,761 Restricted Cash at End of Period (2) — 50 951 Cash, Cash Equivalents, and Restricted Cash at End of Period $ 16,332 $ 12,726 $ 15,712 (1) Greenfield Member contributed approximately $18.8 million of the amount held in escrow at December 31, 2017 for the Black Diamond Acquisition. (2) Restricted cash represents the amount held as collateral at December 31, 2018 for certain of our letters of credit. Concentration of Credit Risk For the year ended December 31, 2020, revenues from Noble comprised 81% and 51% of our midstream services revenues and total revenues, respectively. Revenues from a single third-party customer comprised 40% and 15% of our crude oil sales revenue and total revenues, respectively. For the year ended December 31, 2019, revenues from Noble comprised 81% and 59% of our midstream services revenues and total revenues, respectively. There were no individually significant revenues from a third-party in 2019. For the year ended December 31, 2018, revenues from Noble comprised 81% and 61% of our midstream services revenues and total revenues, respectively. Revenues from a single third-party customer comprised 66% and 17% of our crude oil sales revenues and total revenues, respectively. Revenue Recognition We generate revenues by charging fees on a per unit basis for gathering crude oil and natural gas, delivering and storing fresh water, and collecting, cleaning and disposing of produced water. Also, we purchase crude oil from producers and sell crude oil to customers at various delivery points. We adopted ASC 606 on January 1, 2018, using the modified retrospective method. Under ASC 606, performance obligations are the unit of account and generally represent distinct goods or services that are promised to customers. The adoption of ASC 606 did not have an impact on the recognition, measurement and presentation of our revenues and expenses. See Note for disaggregation of revenue by reportable segment. Performance Obligations For gathering crude oil and natural gas, treating crude oil, processing natural gas, delivering and storing fresh water, and collecting, cleaning and disposing of produced water, our performance obligations are satisfied over time using volumes delivered to measure progress. We record revenue related to the volumes delivered at the contract price at the time of delivery. We began generating revenue from crude oil sales during first quarter 2018 upon closing of the Black Diamond Acquisition. An affiliate of Black Diamond engages in the purchase and sale of crude oil. For our crude oil sales, each unit sold is generally considered a distinct good and the related performance obligation is generally satisfied at a point in time (i.e. at the time control of the crude oil is transferred to the customer). We recognize revenue from the sale of crude oil when our contracted performance obligation to deliver crude oil is satisfied and control of the crude oil is transferred to the customer. This usually occurs when the crude oil is delivered to the location specified in the contract and the title and risks of rewards and ownership are transferred to the customer. Transaction Price Allocated to Remaining Performance Obligations Revenues expected to be recognized from certain performance obligations that are unsatisfied as of December 31, 2020 amount to $37.6 million. We have utilized the practical expedients in ASC 606, which state that we are not required to disclose the transaction price allocated to remaining performance obligations if the variable consideration is allocated entirely to a wholly unsatisfied performance obligation or the transaction price allocated to remaining performance obligations if the performance obligation is part of an agreement that has an original expected duration of one year or less. Contract Balances Under our revenue agreements, we invoice customers after our performance obligations have been satisfied, at which point payment is unconditional. As such, our revenue agreements do not give rise to contract assets or liabilities under ASC 606. The following is a summary of our types of revenue agreements: Crude Oil Gathering Under our crude oil gathering agreements, we receive a volumetric fee per barrel (“Bbl”) for the crude oil gathering services we provide. Natural Gas Gathering Under our natural gas gathering agreements, we receive a fee per the contracted unit of measure for the natural gas gathering services we provide. Natural Gas Processing Under our natural gas gathering agreements, we receive a fee per million British Thermal Units (“MMBtu”) for the natural gas processing services we provide. Natural Gas Compression Under our natural gas compression agreements, we receive a volumetric fee per thousand cubic feet (“Mcf”) for the natural gas compression services we provide. Produced Water Services Under our produced water services agreements, we receive a fee for collecting, cleaning or otherwise disposing of water produced from operating crude oil and natural gas wells in the dedication area. The fee is comprised of a volumetric component for services we provide directly and a pass through component for services we provide through contracts with third parties. Fresh Water Services Under our fresh water services agreements, we receive a fee for delivering fresh water. The fee is comprised of a volumetric component for services we provide directly and a pass through component for services we provide through contracts with third parties. The cost of storing the fresh water is included in the delivery fee. Crude Oil Treating Under our crude oil treating agreements, we receive a monthly fee for the crude oil treating services we provide based on each well operated by Noble that is producing in paying quantities that is not connected to our crude oil gathering systems during such month. Crude Oil Purchase and Sale Under our commodity purchase and sale agreements, we purchase crude oil from producers and sell crude oil to customers at various delivery points. For purchase and sale transactions with the same counterparty, the purchase and sale is settled at the contractual price index on a net basis. We account for these transactions on a net basis, in accordance with ASC 845, Non-Monetary Exchanges . We record the residual fee as gathering revenue in our consolidated statements of operations. For purchase and sale transactions with different counterparties, we purchase the crude oil at market-based prices and sell the crude oil to a different counterparty at market-based prices. Market-based pricing is based on the price index applicable for the location of the sale. We account for these transactions on a gross basis. Recently Adopted Accounting Standards Clarifying Certain Accounting Standards Codification (“ASC”) Topics In first quarter 2020, the FASB issued ASU No. 2020-01: Investments - Equity Securities (Topic 321), Investments - Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815), to clarify the interactions between these Topics. The update provides clarifications for entities investing in equity securities accounted for under the ASC 321 measurement alternative and companies that hold certain non-derivative forward contracts and purchased options to acquire equity securities. ASU 2020-01 is effective for fiscal years beginning after December 15, 2020, with early adoption permitted. We early adopted this ASU in first quarter 2020. This adoption did not have a material impact on our financial statements. Recently Issued Accounting Standards LIBOR Reform In first quarter 2020, the FASB issued ASU No. 2020-04 (ASU 2020-04): Reference Rate Reform (Topic 848), which provides optional guidance for a limited period of time to ease the transition from LIBOR to an alternative reference rate. The ASU intends to address certain concerns stakeholders raised relating to accounting for contract modifications and hedge accounting. These optional expedients and exceptions to applying GAAP, assuming certain criteria are met, are allowed through December 31, 2022. We are currently evaluating the provisions of ASU 2020-04 and have not yet determined whether we will elect the optional expedients. We do not expect the transition to an alternative rate to have a significant impact on our business, operations or liquidity.

Transactions with Affiliates

Transactions with Affiliates	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Transactions with Affiliates	Note 3. Transactions with Affiliates Common Control Transactions Drop-Down and Simplification Transaction On November 14, 2019, we entered into a Contribution, Conveyance, Assumption and Simplification Agreement with Noble in which we acquired (i) the remaining 60% limited partner interest in Blanco River DevCo LP, (ii) the remaining 75% limited partner interest in Green River DevCo LP, (iii) the remaining 75% limited partner interest in San Juan River DevCo LP and (iv) all of the issued and outstanding limited liability company interests of NBL Holdings, which owns a natural gas processing complex in the DJ Basin and an incremental three-stream gathering system in the Delaware Basin. Additionally, all of Noble’s IDRs were converted into Common Units. The total consideration paid by the Partnership for the Drop-Down and Simplification Transaction was $1.6 billion, which consisted of $670 million in cash and 38,455,018 Common Units issued to Noble. The cash portion of the consideration was funded by the Private Placement and borrowings under our revolving credit facility. The transaction closed on November 21, 2019. See Note . Revenue and Expense Transactions with Affiliates Revenues We derive a substantial portion of our revenues from commercial agreements with Noble. Revenues generated from commercial agreements with Noble consist of the following: Year Ended December 31, (in thousands) 2020 2019 2018 Gathering and Processing $ 328,411 $ 337,086 $ 265,505 Fresh Water Delivery 57,834 77,566 69,266 Other 2,947 3,183 3,976 Total Midstream Services — Affiliate $ 389,192 $ 417,835 $ 338,747 Expenses General and administrative expense consists of the following: Year Ended December 31, (in thousands) 2020 2019 2018 General and Administrative Expense — Affiliate $ 14,957 $ 8,523 $ 8,846 General and Administrative Expense — Third Party 9,764 17,254 17,064 Total General and Administrative Expense $ 24,721 $ 25,777 $ 25,910 Reimbursement for Employee Costs All of the employees required to conduct and support our operations are employed by Chevron and are subject to the operational services and secondment agreement and omnibus agreement. Employee costs associated with capital projects are capitalized and employee costs associated with operational projects are recorded to direct operating expense. For the year ended December 31, 2020, the Partnership incurred approximately $5.4 million and $16.6 million in capital project and operational employee costs, respectively. For the year ended December 31, 2019, the Partnership incurred approximately $6.6 million and $16.3 million in capital project and operational employee costs, respectively. For the year ended December 31, 2018, the Partnership incurred approximately $7.2 million and $13.9 million in capital project and operational employee costs, respectively. Agreements with Noble We have entered into various agreements with Noble, as summarized below: Commercial Agreements Our commercial agreements with Noble provide for fees based on the type and scope of the midstream services we provide and the midstream system we use to provide our services, as follows: • Crude Oil Gathering Agreement - Under the applicable crude oil gathering agreement, we receive a volumetric fee per barrel (“Bbl”) for the crude oil gathering services we provide. • Natural Gas Gathering Agreement - Under the natural gas gathering agreement, we receive a volumetric fee per contracted unit of measure for the natural gas gathering services we provide. • Produced Water Services Agreement - Under the applicable produced water services agreement, we receive a fee for collecting, cleaning or otherwise disposing of water produced from operating crude oil and natural gas wells in the dedication area. The fee is comprised of a volumetric component for services we provide directly and a pass through component for services we provide through contracts with third parties. • Fresh Water Services Agreement - Under the applicable fresh water services agreement, we receive a fee for delivering fresh water. The fee is comprised of a volumetric component for services we provide directly and a pass through component for services we provide through contracts with third parties. The cost of storing the fresh water is included in the delivery fee. • Crude Oil Treating Agreement - Under the crude oil treating agreement, we receive a monthly fee for the crude oil treating services we provide based on each well operated that is producing in paying quantities that is not connected to our crude oil gathering systems during such month. • Natural Gas Processing Agreement - Under the natural gas processing agreement, we receive a volumetric fee per MMBtu for the natural gas processing services we provide. • Natural Gas Compression Agreement - Under the applicable natural gas compression agreement, we receive a volumetric fee per thousand cubic feet (“Mcf”) for the natural gas compression services we provide. Our commercial agreements with Noble include a provision to escalate volumetric fees annually, subject to specific limitations within each agreement. In addition, we can propose a redetermination of the fees charged under our various systems on an annual basis, taking into account, among other things, expected capital expenditures necessary to provide our services under the applicable development plan. However, if we are unable to agree on a fee redetermination (other than the automatic annual adjustment), the prior fee will remain in effect. In accordance with our commercial agreements with Noble, we provide midstream services through the use of our midstream assets. We have determined that the structure of our commercial agreements conveys the right to use our midstream assets. Revenues generated from the commercial agreements are recorded within Midstream Services - Affiliate in our consolidated statement of operations. We believe recording within Midstream Services - Affiliate reflects the nature of the commercial agreement, is representative of the revenues generated by the midstream industry and provides our investors with the information necessary to evaluate our operations. Omnibus Agreement Our omnibus agreement with Noble provides for: • our payment of an annual general and administrative fee for the provision of certain administrative and support services by Noble. The rate is redetermined annually and the current rate, which became effective March 1, 2020, is $15.7 million. During February 2021, we completed the annual redetermination process and have established an annual rate of $18.0 million, effective March 1, 2021.; • our right of first refusal on Noble’s existing and future acquired assets and the right to provide certain services, including the right to provide crude oil gathering, natural gas gathering and processing, and water services on certain acreage owned, or to be acquired, by Noble; • our right of first offer to acquire Noble’s retained interest in Gunnison River DevCo LP; and • an indemnity by Noble for certain environmental and other liabilities, and our obligation to indemnify Noble for events and conditions associated with the operations of its assets that occur after the closing of the IPO and for environmental liabilities related to our assets to the extent Noble is not required to indemnify us. Operational Services Agreement Our Operational Services and Secondment Agreement (“Operational Services Agreement”) with Noble provides for: • secondment of certain operational, construction, design and management employees and contractors to our General Partner, us and our subsidiaries to provide management, maintenance and operational functions with respect to our assets. These functions include performing the activities and day-to-day management of the business pursuant to certain commercial agreements listed in the Operational Services Agreement, and designing, building, constructing and otherwise installing the infrastructure required by such agreements; • reimbursement by us to Noble of the cost of the seconded employees and contractors, including their wages and benefits, based on the percentage of the employee’s or contractor’s time spent working for us; and • an initial term of 15 years and automatic extensions for successive renewal terms of one year each, unless terminated by either party.

Offerings and Acquisition

Offerings and Acquisition	12 Months Ended
	Dec. 31, 2020
Business Combinations [Abstract]
Offerings and Acquisition	Note 4. Offerings and Acquisition Offerings Private Placement On November 14, 2019, the Partnership entered into a Common Unit Purchase Agreement with certain institutional investors, pursuant to which the Partnership agreed to sell 12,077,295 Common Units in a private placement (the “Private Placement”). Gross proceeds totaled approximately $250 million. Net proceeds totaled approximately $242.9 million, after deducting offering expenses of approximately $7.1 million. The Private Placement closed on November 21, 2019. Proceeds from the Private Placement were utilized to fund a portion of the cash consideration for the Drop-Down and Simplification Transaction. Preferred Unit Offering On March 25, 2019, we, through Dos Rios Crude Intermediate LLC, a wholly-owned subsidiary of Dos Rios DevCo LLC, secured a $200 million equity commitment from GIP CAPS Dos Rios Holding Partnership, L.P. (“GIP”), an affiliate of Global Infrastructure Partners Capital Solutions Fund. Upon securing the GIP equity commitment, we issued 100,000 preferred equity units, with a face value of $1,000 per preferred unit. Proceeds from the issuance of the preferred equity totaled $100 million. The preferred equity is perpetual and has a 6.5% annual dividend rate. The remaining $100 million equity commitment is available for a one-year period, subject to certain conditions precedent. The following table provides a reconciliation of our redeemable noncontrolling interest balance: Year Ended December 31, (in thousands) 2020 2019 Redeemable Noncontrolling Interest, Beginning Balance $ 106,005 $ — Preferred Equity Issuance — 100,000 Issuance Costs — (3,435) Preferred Equity Accretion (1) 13,653 9,440 Redeemable Noncontrolling Interest, Ending Balance $ 119,658 $ 106,005 (1) Includes dividends paid-in-kind of approximately $7.0 million and $5.0 million for the years ended December 31, 2020 and 2019, respectively. The dividend for each quarter in 2019 and 2020 was paid-in-kind. Acquisition Black Diamond Acquisition On January 31, 2018, Black Diamond completed the Black Diamond Acquisition for approximately $638.5 million in cash. Black Diamond Gathering Holdings LLC (the “Noble Member ”) and the Greenfield Member each funded its share of the purchase price, approximately $319.9 million and $318.6 million, respectively, through contributions to Black Diamond. Noble Member funded its share of the purchase price through a combination of cash on hand and borrowings under its revolving credit facility. See Note . In addition to the payment to the Seller, Black Diamond, through an additional contribution from Greenfield Member, paid PDC Energy, Inc. (“PDC Energy”) approximately $24.1 million to expand PDC Energy’s acreage dedication as well as extend the duration of the acreage dedication by five years. In accordance with the limited liability company agreement of Black Diamond, Noble Member received a 54.4% equity ownership interest in Black Diamond and Greenfield Member received a 45.6% equity ownership interest in Black Diamond. Noble Member’s agreed equity ownership interest included a 4.4% equity ownership interest promote which was designed to vest only after Noble Member was allocated an amount of gross revenue equal to the contributions by Greenfield Member in excess of its agreed equity ownership interest. As of December 31, 2020, Noble Member has received the necessary allocations of gross revenue and the equity ownership interest promote has vested. See Note . We serve as the operator of the Black Diamond system. We acquired a large-scale integrated gathering system located in the DJ Basin with approximately 160 miles of pipeline in operation and delivery capacity of approximately 300 MBbl/d as well as approximately 141,000 dedicated acres from six customers under fixed-fee arrangements. In connection with the Black Diamond Acquisition, we incurred acquisition and integration costs of $6.8 million during the year ended December 31, 2018. Our acquisition and integration costs include consulting, advisory, legal, transition services and other fees. All acquisition and integration costs were expensed and are included in general and administrative expense in our consolidated statements of operations. The transaction has been accounted for as a business combination, using the acquisition method. The following table represents the final allocation of the total Black Diamond Acquisition purchase price to the assets acquired and the liabilities assumed based on the fair value at the acquisition date, with any excess of the purchase price over the estimated fair value of the identifiable net assets acquired recorded as goodwill. The following table sets forth our purchase price allocation: (in thousands) Cash Consideration $ 638,266 PDC Energy Payment 24,120 Current Liabilities Assumed 18,259 Total Purchase Price and Liabilities Assumed $ 680,645 Cash and Restricted Cash $ 12,518 Accounts Receivable 10,661 Other Current Assets 2,206 Property, Plant and Equipment 205,766 Intangible Assets (1) 339,760 Fair Value of Identifiable Assets 570,911 Implied Goodwill (2) 109,734 Total Asset Value $ 680,645 (1) See Note . (2) Recognized goodwill was assigned to the Black Diamond reporting unit within the Gathering Systems reportable segment. This amount was fully impaired in first quarter 2020.

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Note 5. Property, Plant and Equipment Property, plant and equipment, at cost, is as follows: (in thousands) December 31, 2020 December 31, 2019 Gathering and Processing Systems $ 1,924,125 $ 1,795,957 Fresh Water Delivery Systems (1) 95,849 96,004 Construction-in-Progress (2) 54,816 115,034 Total Property, Plant and Equipment, at Cost 2,074,790 2,006,995 Accumulated Depreciation and Amortization (315,441) (244,038) Property, Plant and Equipment, Net $ 1,759,349 $ 1,762,957 (1) Fresh water delivery system assets at December 31, 2020 and December 31, 2019 include $5.0 million related to a leased pond accounted for as a finance lease. See Note . (2) Construction-in-progress at December 31, 2020 primarily includes $43.8 million in gathering system projects and $9.5 million in equipment for use in future projects. Construction-in-progress at December 31, 2019 primarily includes $98.4 million in gathering system projects and $15.4 million in equipment for use in future projects.

Investments

Investments	12 Months Ended
	Dec. 31, 2020
Investments, All Other Investments [Abstract]
Investments	Note 6. Investments We have ownership interests in the following entities: • 3% interest in White Cliffs; • 50% interest in Advantage; • 50% interest in Delaware Crossing; • 30% interest in EPIC Crude; • 15% interest in EPIC Y-Grade; • 15% interest in EPIC Propane; and • 20% interest in Saddlehorn. Advantage In April 2017, we acquired the interest in Advantage for $66.8 million. Advantage owns a crude oil pipeline system in the Southern Delaware Basin. Delaware Crossing In February 2019, we executed definitive agreements with Salt Creek and completed the formation of Delaware Crossing, which constructed a crude oil pipeline system in the Delaware Basin. During 2020, we made capital contributions of $14.8 million. EPIC Crude In January 2019, we exercised our option with EPIC to acquire an interest in EPIC Crude Holdings, which constructed the EPIC crude oil pipeline from the Delaware Basin to Corpus Christi, Texas. On March 8, 2019, we closed our option with EPIC to acquire the interest in EPIC Crude. During 2020, we made capital contributions of $58.5 million. EPIC Y-Grade In January 2019, we exercised and closed our option with EPIC Midstream Holdings, LP (“EPIC”) to acquire an interest in EPIC Y-Grade, which owns the EPIC Y-Grade pipeline from the Delaware Basin to Corpus Christi, Texas. During 2020, we made capital contributions of $44.9 million. Additionally, our loan to EPIC Y-Grade plus accrued interest was converted to equity and treated as a capital contribution. See Note . EPIC Propane In December 2019, we exercised and closed an option with EPIC to acquire an interest in EPIC Propane, which is constructing a propane pipeline that will run from the EPIC Y-Grade Logistics, LP fractionator complex in Robstown, Texas to the Phillips 66 petrochemical facility in Sweeney, Texas, with additional connectivity to the Markham underground storage caverns. EPIC Propane completed construction of its first new build fractionator in July 2020. During 2020, we made capital contributions of $10.1 million. Saddlehorn In February 2020, Black Diamond exercised its option to acquire a 20% ownership interest in Saddlehorn for $160.0 million, or $87.0 million net to the Partnership. The Saddlehorn pipeline transports crude oil and condensate from the DJ Basin and the Powder River Basin to storage facilities in Cushing, Oklahoma, and, after expansion, will have total capacity of 290 MBbl/d. Saddlehorn is jointly owned by affiliates of Magellan Midstream Partners, L.P. (“Magellan”), Plains All American Pipeline, L.P. (“Plains”) and Western Midstream Partners, LP (“Western Midstream”). After Black Diamond’s purchase, with Magellan and Plains each selling a 10% interest, Magellan and Plains will each own a 30% membership interest and Black Diamond and Western Midstream will each own a 20% membership interest in Saddlehorn. Magellan continues to serve as operator of the Saddlehorn pipeline. The Partnership funded its share of the transaction price with available cash and a draw under its revolving credit facility. The following table presents our investments at the dates indicated: (in thousands) December 31, 2020 December 31, 2019 White Cliffs $ 10,204 $ 10,268 Advantage (1) 72,500 76,834 Delaware Crossing 81,476 68,707 EPIC Crude 373,623 339,116 EPIC Y-Grade 194,188 162,850 EPIC Propane 12,905 3,003 Saddlehorn (2) 160,059 — Total Investments (3) $ 904,955 $ 660,778 (1) Distributions from Advantage totaled $12.0 million and $10.1 million during the years ended December 31, 2020 and 2019, respectively. (2) Distributions from Saddlehorn totaled $25.0 million during the year ended December 31, 2020. (3) We have capitalized $33.8 million in expenses that are included in the basis of the investments. The capitalized items include acquisition related expenses and capitalized interest. Unamortized capitalized expenses totaled $32.8 million and $27.7 million as of December 31, 2020 and December 31, 2019, respectively. The following table presents our investment loss (income) for the periods indicated: Year Ended December 31, (in thousands) 2020 2019 2018 White Cliffs $ (1,844) $ (3,107) $ (3,687) Advantage (6,103) (8,159) (11,880) Delaware Crossing 3,390 3,061 — EPIC Crude 26,663 19,152 — EPIC Y-Grade 38,425 8,381 — EPIC Propane 300 — — Saddlehorn (24,199) — — Other (1) (1,741) (1,580) (722) Total Investment Loss (Income) $ 34,891 $ 17,748 $ (16,289) (1) Represents our fee for serving as the operator of Advantage and Delaware Crossing. Summarized, 100% combined balance sheet information for equity method investments was as follows: (in thousands) December 31, 2020 December 31, 2019 Current Assets $ 427,337 $ 304,057 Noncurrent Assets 5,261,349 4,296,648 Current Liabilities 329,779 443,573 Noncurrent Liabilities 2,099,429 1,868,138 Summarized, 100% combined statements of operations for equity method investments was as follows: Year Ended December 31, (in thousands) 2020 2019 2018 Operating Revenues $ 760,925 $ 481,466 $ 35,153 Operating Expenses 878,579 575,306 11,148 Operating (Loss) Income (117,654) (93,840) 24,005 Other Expense (Income) 147,128 41,616 (37) (Loss) Income Before Income Taxes (264,782) (135,456) 24,042 Tax Expense 96 118 171 Net (Loss) Income $ (264,878) $ (135,574) $ 23,871

Intangible Assets

Intangible Assets	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	Note 7. Intangible Assets Our intangible assets are as follows: December 31, 2020 December 31, 2019 (in thousands) Gross Accumulated Amortization (1) Net Gross Accumulated Amortization (1) Net Customer Contracts and Relationships $ 339,760 $ 94,250 $ 245,510 $ 339,760 $ 61,860 $ 277,900 (1) For the years ended December 31, 2020 and 2019, amortization expense related to intangible assets totaled $32.4 million and $32.3 million, respectively. Estimated future amortization expense related to the intangible assets at December 31, 2020 is as follows: (in thousands) December 31, 2020 2021 $ 32,301 2022 32,301 2023 32,301 2024 32,390 2025 27,871 Thereafter 88,346 Total $ 245,510

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Long-Term Debt	Note 8. Long-Term Debt Long-term debt as of December 31, 2020 and December 31, 2019 was as follows: December 31, 2020 December 31, 2019 (in thousands, except percentages) Debt Interest Rate Debt Interest Rate Revolving Credit Facility, due March 9, 2023 $ 710,000 1.61 % $ 595,000 3.11 % 2018 Term Loan Credit Facility, due July 31, 2021 500,000 1.36 % 500,000 2.85 % 2019 Term Loan Credit Facility, due August 23, 2022 400,000 1.24 % 400,000 2.74 % Finance Lease Obligation (1) 2,063 — % 2,005 — % Total 1,612,063 1,497,005 Term Loan Credit Facilities Unamortized Debt Issuance Costs (555) (1,326) Total Debt 1,611,508 1,495,679 Less Amounts Due Within One Year 2018 Term Loan Credit Facility, due July 31, 2021, Net (499,793) — Finance Lease Obligation (1) (2,063) — Long-Term Debt $ 1,109,652 $ 1,495,679 (1) See Note and Note . Revolving Credit Facility We maintain a revolving credit facility to fund working capital and to finance acquisitions and expansion capital expenditures. Our revolving credit facility has a total borrowing capacity of $1.15 billion and as of December 31, 2020, we had $440 million available for borrowing. In 2020, we utilized our revolving credit facility to fund our capital contributions to Saddlehorn, Delaware Crossing, EPIC Crude, EPIC Y-Grade and EPIC Propane. Borrowings under the revolving credit facility bear interest at a rate equal to an applicable margin plus, at our option, either (a) in the case of base rate borrowings, a rate equal to the highest of (1) the prime rate, (2) the greater of the federal funds rate or the overnight bank funding rate, plus 0.5% and (3) the LIBOR for an interest period of one month plus 1.0%; or (b) in the case of LIBOR borrowings, the offered rate per annum for deposits of dollars for the applicable interest period. The unused portion of the revolving credit facility is subject to a commitment fee. As of December 31, 2020 and December 31, 2019, the commitment fee rate was 0.275% and 0.275%, respectively. Unamortized debt issuance costs totaled $2.1 million and $3.0 million as of December 31, 2020 and December 31, 2019, respectively, and are recorded within other noncurrent assets in our consolidated balance sheets. The revolving credit facility requires us to comply with certain financial covenants as of the end of each fiscal quarter. We were in compliance with such covenants as of December 31, 2020. Certain lenders that are a party to the credit agreement have in the past performed, and may in the future from time to time perform, investment banking, financial advisory, lending or commercial banking services for us for which they have received, and may in the future receive, customary compensation and reimbursement of expenses. Term Loan Credit Facilities On August 23, 2019, we entered into a three-year senior unsecured term loan credit facility that permits aggregate borrowings of up to $400 million (the “2019 Term Loan”). Borrowings under the 2019 Term Loan bear interest at a rate equal to, at our option, either (1) a base rate plus an applicable margin between 0.00% and 0.375% per annum or (2) a Eurodollar rate plus an applicable margin between 0.875% and 1.375% per annum. On July 31, 2018, we entered into a three-year senior unsecured term loan credit facility that permits aggregate borrowings of up to $500 million (the “2018 Term Loan”). Borrowings under the 2018 Term Loan bear interest at a rate equal to, at our option, either (1) a base rate plus an applicable margin between 0.00% and 0.50% per annum or (2) a Eurodollar rate plus an applicable margin between 1.00% and 1.50% per annum. This credit facility is classified within short-term debt on our consolidated balance sheets as it is due on July 31, 2021. The term loan credit facilities contain customary representations and warranties, affirmative and negative covenants, and events of default that are substantially the same as those contained in our revolving credit facility, including the requirement to comply with certain financial covenants as of the end of each fiscal quarter. We were in compliance with such covenants as of December 31, 2020. Upon the occurrence and during the continuation of an event of default under the term loan credit facilities, the lenders may declare all amounts outstanding under the term loan credit facilities to be immediately due and payable and exercise other remedies as provided by applicable law.

Asset Retirement Obligations

Asset Retirement Obligations	12 Months Ended
	Dec. 31, 2020
Asset Retirement Obligation Disclosure [Abstract]
Asset Retirement Obligations	Note 9. Asset Retirement Obligations AROs consist of estimated costs of dismantlement, removal, site reclamation and similar activities associated with our infrastructure assets. Changes in AROs are as follows: Year Ended December 31, (in thousands) 2020 2019 Asset Retirement Obligations, Beginning Balance $ 37,842 $ 30,533 Liabilities Incurred 657 1,912 Liabilities Settled (46) (131) Revision of Estimate 1,380 3,686 Accretion Expense (1) 1,739 1,842 Asset Retirement Obligations, Ending Balance $ 41,572 $ 37,842 (1) Accretion expense is included in depreciation and amortization expense in the consolidated statements of operations. Liabilities incurred in 2020 were primarily related to new pipeline installations in the Mustang IDP area and Delaware Basin. Revisions of estimates were primarily related to an increase in estimated costs associated with the retirement of our CGFs. Liabilities incurred in 2019 were primarily related to new pipeline installations in the Mustang IDP area, Greeley Crescent IDP area and Delaware Basin. Revisions of estimates were primarily related to an increase in estimated costs associated with the abandonment of Delaware Basin pipelines and an increase in estimated costs associated with the retirement of our CGFs.

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Segment Information	Note 10. Segment Information We manage our operations by the nature of the services we offer. Our reportable segments comprise the structure used to make key operating decisions and assess performance. We are organized into the following reportable segments: Gathering Systems (primarily includes crude oil gathering, natural gas gathering and processing, produced water gathering, and crude oil sales), Fresh Water Delivery, Investments in Midstream Entities and Corporate. We often refer to the services of our Gathering Systems and Fresh Water Delivery reportable segments collectively as our midstream services. Prior period segment information has been reclassified to conform to the current period presentation. Summarized financial information concerning our reportable segments is as follows: (in thousands) Gathering Systems Fresh Water Delivery Investments in Midstream Entities Corporate (1) Consolidated Year Ended December 31, 2020 Midstream Services — Affiliate $ 331,358 $ 57,834 $ — $ — $ 389,192 Midstream Services — Third Party 86,548 7,680 — — 94,228 Crude Oil Sales — Third Party 281,205 — — — 281,205 Total Revenues 699,111 65,514 — — 764,625 Cost of Crude Oil Sales 270,678 — — — 270,678 Direct Operating Expense 80,214 8,663 — 3,510 92,387 Depreciation and Amortization 102,784 2,913 — — 105,697 Goodwill Impairment 109,734 — — — 109,734 Income (Loss) Before Income Taxes 131,003 53,939 (34,891) (54,802) 95,249 Year Ended December 31, 2019 Midstream Services — Affiliate $ 340,269 $ 77,566 $ — $ — $ 417,835 Midstream Services — Third Party 83,603 12,591 — — 96,194 Crude Oil Sales — Third Party 189,772 — — — 189,772 Total Revenues 613,644 90,157 — — 703,801 Cost of Crude Oil Sales 181,390 — — — 181,390 Direct Operating Expense 95,743 18,650 — 2,282 116,675 Depreciation and Amortization 94,455 2,526 — — 96,981 Income (Loss) Before Income Taxes 242,545 68,980 (17,748) (44,295) 249,482 Year Ended December 31, 2018 Midstream Services — Affiliate $ 269,481 $ 69,266 $ — $ — $ 338,747 Midstream Services — Third Party 59,153 19,345 — — 78,498 Crude Oil Sales — Third Party 141,490 — 141,490 Total Midstream Services Revenues 470,124 88,611 — — 558,735 Direct Operating Expense 79,848 14,269 — 1,735 95,852 Depreciation and Amortization 77,309 2,259 — — 79,568 Income (Loss) Before Income Taxes 172,826 72,083 16,289 (36,478) 224,720 December 31, 2020 Intangible Assets, Net $ 245,510 $ — $ — $ — $ 245,510 Goodwill — — — — — Total Assets 2,014,935 105,599 904,955 11,707 3,037,196 Additions to Long-Lived Assets 70,118 — 317,229 523 387,870 December 31, 2019 Intangible Assets, Net $ 277,900 $ — $ — $ — $ 277,900 Goodwill 109,734 — — — 109,734 Total Assets 2,160,026 91,840 660,778 13,438 2,926,082 Additions to Long-Lived Assets 257,066 7,330 611,325 1,068 876,789 (1) The Corporate segment includes all general Partnership activity not attributable to our operating subsidiaries.

Unit-Based Compensation

Unit-Based Compensation	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Unit-Based Compensation	Note 11. Unit-Based Compensation The Noble Midstream Partners LP 2016 Long-Term Incentive Plan (the “LTIP”) provides for the grant, at the discretion of the board of directors of our General Partner, of unit awards, restricted units, phantom units, unit options, unit appreciation rights, distribution equivalent rights, profits interest units and other unit-based awards. The purpose of awards under the LTIP is to provide additional incentive compensation to individuals providing services to us, and to align the economic interests of such individuals with the interests of our unitholders. The LTIP limits the number of units that may be delivered pursuant to vested awards to 1,860,000 Common Units, subject to proportionate adjustment in the event of unit splits and similar events. Common units subject to awards that are canceled, forfeited, withheld to satisfy exercise prices or tax withholding obligations or otherwise terminated without delivery of Common Units will be available for delivery pursuant to other awards. As of December 31, 2020, 1,484,907 Common Units are available for future grant under the LTIP. Restricted unit activity for the year ended December 31, 2020 was as follows: Number of Units Weighted Average Award Date Fair Value Awarded and Unvested Units at December 31, 2019 103,355 $ 36.04 Awarded 145,731 22.40 Vested (48,809) 36.41 Forfeited (27,194) 25.92 Awarded and Unvested Units at December 31, 2020 173,083 $ 26.04 Unit based compensation expense is recorded within general and administrative expense. For the years ended December 31, 2020, December 31, 2019 and December 31, 2018, our unit based compensation expense was approximately $2.2 million, $1.1 million, $1.4 million, respectively. As of December 31, 2020, $2.4 million of compensation cost related to all of our unvested restricted units awarded under the LTIP remained to be recognized. The cost is expected to be recognized over a weighted-average period of 1.3 years.

Partnership Distributions

Partnership Distributions	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Partnership Distributions	Note 12. Partnership Distributions Our partnership agreement requires that, within 45 days after the end of each quarter, we distribute all of our available cash to unitholders of record on the applicable record date. The following table details the distributions paid in respect of the periods presented below: Distributions (in thousands except per unit amounts) Limited Partners Period Record Date Distribution Date Distribution per Limited Partner Unit Common Unitholders (1) Subordinated Unitholders (2) Holder of IDRs (3) Total Q4 2017 February 5, 2018 February 12, 2018 $ 0.4883 $ 11,566 $ 7,765 $ 520 $ 19,851 Q1 2018 May 7, 2018 May 14, 2018 0.5110 12,103 8,126 819 21,048 Q2 2018 August 6, 2018 August 13, 2018 0.5348 12,668 8,504 1,134 22,306 Q3 2018 November 5, 2018 November 13, 2018 0.5597 13,258 8,901 1,462 23,621 Q4 2018 February 4, 2019 February 11, 2019 0.5858 13,876 9,316 2,421 25,613 Q1 2019 May 6, 2019 May 13, 2019 0.6132 14,534 9,751 3,507 27,792 Q2 2019 August 5, 2019 August 12, 2019 0.6418 25,418 — 4,640 30,058 Q3 2019 November 4, 2019 November 12, 2019 0.6716 26,598 — 5,820 32,418 Q4 2019 February 4, 2020 February 14, 2020 0.6878 62,012 — — 62,012 Q1 2020 May 8, 2020 May 15, 2020 0.1875 16,906 — — 16,906 Q2 2020 August 7, 2020 August 14, 2020 0.1875 16,907 — — 16,907 Q3 2020 November 6, 2020 November 13, 2020 0.1875 16,907 — — 16,907 (1) Distributions to common unitholders do not include distribution equivalent rights on units that vested under the LTIP. (2) See Conversion of Subordinated Units, below. (3) In November 2019, we acquired all of Noble ’s IDRs. See Note 3. Transactions with Affiliates . Conversion of Subordinated Units On April 25, 2019, the board of directors of our General Partner declared a quarterly cash distribution of $0.6132 per unit f or the quarter ended March 31, 2019. The distribution was paid on May 13, 2019 to unitholders of record as of the close of business on May 6, 2019. Upon payment of the distribution, the requirements for the conversion of all Subordinated Units were satisfied under our partnership agreement. As a result, on May 14, 2019, all 15,902,584 Subordinated Units, which were owned entirely by Noble, converted into Common Units on a one-for-one basis and thereafter will participate on terms equal with all other Common Units in distributions from available cash.

Net Income Per Limited Partner

Net Income Per Limited Partner Unit	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Net Income Per Limited Partner Unit	Note 13. Net Income Per Limited Partner Unit The Partnership’s net income is attributed to limited partners, in accordance with their respective ownership percentages, and when applicable, giving effect to incentive distributions paid to Noble. For periods prior to the conversion of Subordinated Units and simplification of IDRs, we had more than one class of participating securities and we utilized the two-class method when calculating the net income per unit applicable to limited partners. The classes of participating securities include Common Units, Subordinated Units and IDRs. Basic and diluted net income per limited partner Common and Subordinated Unit is computed by dividing the respective limited partners’ interest in net income for the period by the weighted-average number of Common and Subordinated Units outstanding for the period. Diluted net income per limited partner Common and Subordinated Unit reflects the potential dilution that could occur if agreements to issue Common Units, such as awards under the LTIP, were settled or converted into Common Units. When it is determined that potential Common Units resulting from an award should be included in the diluted net income per limited partner Common and Subordinated Unit calculation, the impact is reflected by applying the treasury stock method. Our calculation of net income per limited partner Common and Subordinated Unit is as follows: Year Ended December 31, (in thousands) 2020 2019 2018 Net Income Attributable to Noble Midstream Partners LP $ 134,031 $ 159,996 $ 162,734 Less: Net Income Attributable to Incentive Distribution Rights — 13,967 5,836 Net Income Attributable to Limited Partners $ 134,031 $ 146,029 $ 156,898 Net Income Allocable to Common Units $ 134,031 $ 123,662 $ 93,875 Net Income Allocable to Subordinated Units — 22,367 63,023 Net Income Attributable to Limited Partners $ 134,031 $ 146,029 $ 156,898 Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic Common Units $ 1.49 $ 3.09 $ 3.96 Subordinated Units $ — $ 3.86 $ 3.96 Net Income Attributable to Limited Partners Per Limited Partner Unit — Diluted Common Units $ 1.49 $ 3.08 $ 3.96 Subordinated Units $ — $ 3.86 $ 3.96 Weighted Average Limited Partner Units Outstanding — Basic Common Units 90,165 40,083 23,686 Subordinated Units — 5,795 15,903 Weighted Average Limited Partner Units Outstanding — Diluted Common Units 90,167 40,105 23,701 Subordinated Units — 5,795 15,903 Antidilutive Restricted Units 184 54 24

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 14. Commitments and Contingencies Legal Proceedings We may become involved in various legal proceedings in the ordinary course of business. These proceedings would be subject to the uncertainties inherent in any litigation, and we will regularly assess the need for accounting recognition or disclosure of these contingencies. We will defend ourselves vigorously in all such matters. Based on currently available information, we believe it is unlikely that the outcome of known matters would have a material adverse impact on our combined financial condition, results of operations or cash flows. Clean Water Act Matte r In January 2021, the United States Department of Justice and the United States Environmental Protection Agency notified the Partnership of potential penalties for alleged Clean Water Act violations at a facility in Weld County, Colorado regarding requirements for Spill Prevention and Countermeasures Plan and Facility Response Plan. The parties are negotiating a resolution of this matter. Resolution of these alleged violations may result in the payment of a civil penalty of $300,000 or more. Given the ongoing status of negotiations, we are currently unable to predict the ultimate outcome of this matter, but believe the resolution will not have a material adverse effect on our financial position, results of operations or cash flows. Crude Oil Purchase Commitments An affiliate of Black Diamond enters into agreements to purchase crude oil from producers at market-based prices. The agreements do not contain provisions regarding fixed or minimum quantities of crude oil to be purchased. Minimum commitments as of December 31, 2020 are as follows: (in thousands) Future Minimum Finance Lease Payments Future Minimum Operating Lease Payments Purchase Obligations (1) Transportation Fees (2) Surface Lease Obligations Total 2021 $ 2,063 $ 260 $ 2,064 $ 34,101 $ 217 $ 38,705 2022 — — — 34,195 176 34,371 2023 — — — 34,879 176 35,055 2024 — — — 35,954 176 36,130 2025 — — — 36,576 176 36,752 2026 and Beyond — — — 26,072 3,698 29,770 Total $ 2,063 $ 260 $ 2,064 $ 201,777 $ 4,619 $ 210,783 (1) Purchase obligations represent contractual agreements to purchase goods or services that are enforceable, are legally binding and specify all significant terms, including fixed and minimum quantities to be purchased; fixed, minimum or variable price provisions; and the approximate timing of the transaction. (2) We have entered into long-term agreements with unaffiliated third parties to satisfy a substantial portion of our transportation commitment.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Note 15. Income Taxes We are not a taxable entity for United States federal income tax purposes or for the majority of states that impose an income tax. Taxes are generally borne by our partners through the allocation of taxable income and we do not record deferred taxes related to the aggregate difference in the basis of our assets for financial and tax reporting purposes. We are subject to a Texas margin tax due to our operations in the Delaware Basin, and we recorded a de minimis state tax provision for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. For periods prior to the Drop-Down and Simplification Transaction, our consolidated financial statements include a provision for tax expense on income related to the assets contributed to the Partnership. Deferred federal and state income taxes were provided on temporary differences between the financial statement carrying amounts of recognized assets and liabilities and their respective tax bases as if the Partnership filed tax returns as a stand-alone entity. The following table presents our tax provision for the periods indicated: Year Ended December 31, (in thousands) 2020 2019 2018 Current $ (161) $ 541 $ 1,323 Deferred 544 3,474 6,678 Tax Provision (1) $ 383 $ 4,015 $ 8,001 Effective Tax Rate 0.4 % 1.6 % 3.6 % (1) A substantial portion of our tax provision represents federal income taxes associated with the assets contributed in the Drop-Down and Simplification Transaction. Net deferred tax liabilities were de minimis at December 31, 2020 and December 31, 2019.

Supplemental Quarterly Financia

Supplemental Quarterly Financial Information	12 Months Ended
	Dec. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Supplemental Quarterly Financial Information	Supplemental quarterly financial information is as follows: (in thousands except per share amounts) First Quarter Second Quarter Third Quarter Fourth Quarter Year Ended December 31, 2020 Total Revenues $ 224,045 $ 145,950 $ 187,365 $ 207,265 Operating Income (25,101) 61,431 62,071 58,309 Income Before Income Taxes (37,367) 50,732 38,902 42,982 Net Income (37,516) 50,860 38,736 42,786 Net Income Attributable to Limited Partners 10,103 48,236 35,784 39,908 Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic Common Units $ 0.11 $ 0.53 $ 0.40 $ 0.44 Year Ended December 31, 2019 Total Revenues $ 160,702 $ 170,660 $ 181,674 $ 190,765 Operating Income 71,987 60,564 81,271 69,644 Income Before Income Taxes 69,100 56,494 71,698 52,190 Net Income 67,791 55,763 70,519 51,394 Net Income Attributable to Limited Partners 40,052 31,769 34,812 39,396 Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic Common Units $ 1.01 $ 0.79 $ 0.88 $ 0.65 Subordinated Units 1.01 0.84 — —

Summary of Significant Accoun_2

Summary of Significant Accounting Policies and Basis of Presentation (Policies)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Presentation	Basis of Presentation and Consolidation Our consolidated financial statements were prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”). All intercompany balances and transactions have been eliminated upon consolidation. The Partnership has no items of other comprehensive income or loss; therefore, its net income is identical to its comprehensive income.
Variable Interest Entities	Variable Interest Entities Our consolidated financial statements include the accounts of Black Diamond, which we control. We have determined that the partners with equity at risk in Black Diamond lack the authority, through voting rights or similar rights, to direct the activities that most significantly impact their economic performance. Therefore, Black Diamond is considered a VIE. Through our majority representation on the Black Diamond board of directors as well as our responsibility as operator of the Black Diamond system, we have the authority to direct the activities that most significantly affect economic performance and the obligation to absorb losses or the right to receive benefits that could be potentially significant to us. Therefore, we are considered the primary beneficiary and consolidate Black Diamond in our financial statements. All financial statement activity associated with Black Diamond is captured within the Gathering Systems reportable segment. See Note .
Equity Method of Accounting	Equity Method of Accounting We use the equity method of accounting for investments in entities that we do not control but over which we exert significant influence. For certain entities, we serve as the operator and exert significant influence over the day-to-day operations. For other entities, we do not serve as the operator; however, our voting position on management committees or the board of directors allows us to exert significant influence over decisions regarding capital investments, budgets, turnarounds, maintenance, monetization decisions and other project matters. Under the equity method of accounting, initially we record the investment at our cost. Differences in the cost, or basis, of the investment and the net asset value of the investee will be amortized into earnings over the remaining useful life of the underlying assets.
Cost Method Accounting	Cost Method of Accounting We use the cost method of accounting for our White Cliffs Interest as we have virtually no influence over its operations and financial policies. Under the cost method of accounting, we recognize cash distributions from White Cliffs Pipeline L.L.C. as investment income in our consolidated statements of operations to the extent there is net income and record cash distributions in excess of our ratable share of earnings as return of investment.
Redeemable Noncontrolling Interest and Noncontrolling Interest	Redeemable Noncontrolling Interest Our redeemable noncontrolling interest is related to our 2019 preferred equity issuance . We can redeem the preferred equity in whole or in part at any time for cash at a predetermined redemption price. The predetermined redemption price is the greater of (i) an amount necessary to achieve a 12% internal rate of return or (ii) an amount necessary to achieve a 1.375x multiple on invested capital. GIP can request redemption of the preferred equity on or after March 25, 2025. As GIP’s redemption right is outside of our control, the preferred equity is not considered to be a component of equity on the consolidated balance sheet, and is reported as mezzanine equity on the consolidated balance sheet. In addition, because the preferred equity was issued by a subsidiary of the Partnership and is held by a third party, it is considered a redeemable noncontrolling interest. The preferred equity was recorded initially at fair value on the issuance date. Subsequent to issuance, we accrete changes in the redemption value of the preferred equity from the date of issuance to GIP’s earliest redemption date. The preferred equity is perpetual and has a 6.5% annual dividend rate, payable quarterly in cash, with the ability to accrue unpaid dividends during the first two years following the closing. During any quarter in which a dividend is accrued, the accreted value of the preferred equity will be increased by the accrued but unpaid dividend (i.e., a paid-in-kind dividend). See Note .
Segment Information	Segment Information   Accounting policies for reportable segments are the same as those described in this footnote. Transfers between segments are accounted for at market value. We do not consider interest income and expense or income tax benefit or expense in our evaluation of the performance of reportable segments.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires us to make a number of estimates and assumptions relating to the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ significantly from those estimates. Management evaluates estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic and commodity price environment.
Cash and Cash Equivalents	Cash and Cash Equivalents For purposes of reporting cash flows, cash and cash equivalents include unrestricted cash on hand and investments with original maturities of three months or less at the time of purchase.
Accounts Receivable and Allowance for Expected Credit Losses	Accounts Receivable and Allowance for Expected Credit Losses
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment primarily consists of crude oil gathering systems, natural gas gathering systems, natural gas plants and compression units, produced water collection, gathering, and cleaning systems, fresh water storage and delivery systems and crude oil treating facilities. Property and equipment is stated at the lower of historical cost less accumulated depreciation, or fair value, if impaired. Capitalized Interest We capitalize construction-related direct labor and incremental costs, such as interest expense. Capitalized interest totaled $5.5 million in 2020, $17.5 million in 2019, and $6.4 million in 2018.
Impairment of Long-Live Assets	Impairment of Long-Lived Assets We routinely assess whether impairment indicators arise during any given quarter and have processes in place to ensure that we become aware of such indicators. Impairment indicators include, but are not limited to, sustained decreases in commodity prices, a decline in customer well results and lower throughput forecasts, changes in customer development plans, and/or increases in our construction or operating costs. In the event that impairment indicators exist, we conduct an impairment test. We evaluate our ability to recover the carrying amounts of long-lived assets and determine whether such long-lived assets have been impaired. Impairment exists when the carrying value of an asset exceeds the estimated undiscounted future cash flows expected to result from the use and eventual disposition of the asset. When the carrying amount of a long-lived asset exceeds its estimated undiscounted future cash flows, the carrying amount of the asset is reduced to its estimated fair value. Fair value may be estimated using comparable market data, a discounted cash flow method, or a combination of the two. During 2018, we recorded an asset impairment of $3.5 million related to a damaged gathering system asset. The asset impairment was partially offset by an expected recovery of $2.5 million. The resulting net impairment totaled $1.0 million and is recorded within other operating expense in our consolidated statement of operations.
Asset Retirement Obligations	Asset Retirement Obligations Asset Retirement Obligations (“AROs”) consist of estimated costs of dismantlement, removal, site reclamation and similar activities associated with our property and equipment. We recognize the fair value of a liability for an ARO in the period in which it is incurred when we have an existing legal obligation associated with the retirement of our infrastructure assets and the obligation can reasonably be estimated. The associated asset retirement cost is capitalized as part of the carrying cost of the infrastructure asset. The recognition of an ARO requires that management make numerous estimates, assumptions and judgments regarding such factors as: the existence of a legal obligation for an ARO; estimated probabilities, amounts and timing of settlements; the credit-adjusted risk-free rate to be used; and inflation rates. In periods subsequent to initial measurement of the ARO, we recognize period-to-period changes in the liability resulting from the passage of time and revisions to either the timing or the amount of the original estimate of undiscounted cash flows. Revisions also result in increases or decreases in the carrying cost of the asset. Increases in the ARO liability due to passage of time impact net income as accretion expense. The related capitalized cost, including revisions thereto, is charged to expense through depreciation and amortization. See Note . With respect to property, plant and equipment associated with the Black Diamond system, it is our practice and current intent to maintain these assets and continue to make improvements as warranted. As a result, we believe that these assets have indeterminate lives for purposes of estimating AROs because dates or ranges of dates upon which we would retire these assets cannot reasonably be estimated at this time; therefore, no AROs have been recorded for these assets as of December 31, 2020 or 2019.
Goodwill	Goodwill Our goodwill was assigned to the Black Diamond reporting unit within the Gathering Systems reportable segment. As discussed above, we performed a qualitative assessment and concluded it was more likely than not that the fair value of the Black Diamond reporting unit was less than its carrying value. We then performed a fair value assessment using the income approach. Our estimate of fair value required us to use significant unobservable inputs, representative of a Level 3 fair value measurement, including assumptions for operating and development costs as well as taking into account changes and uncertainties in our customers’ development outlook. Based on these assessments, we concluded that our goodwill was fully impaired and recorded a non-cash charge of $109.7 million in March 2020. See Note for further details on goodwill.
Investments	Investments We routinely assess our investments for impairment whenever changes in facts and circumstances indicate a loss in value has occurred. When impairment indicators exist, the fair value is estimated and compared to the investment carrying amount. When the carrying amount of an investment exceeds its estimated undiscounted future cash flows, the carrying amount of the investment is reduced to its estimated fair value. Fair value may be estimated using comparable market data, a discounted cash flow method, or a combination of the two.
Intangible Assets	Intangible Assets Our intangible assets are comprised of customer contracts acquired in the Black Diamond Acquisition and recorded under the acquisition method of accounting at their estimated fair values at the date of acquisition. The customer contracts are long-term, fixed-fee contracts for the purchase and sale of crude oil. Amortization is calculated using the straight-line method by customer contract, which reflects the pattern in which the estimated economic benefit is expected to be received over the estimated useful life of the intangible asset. The estimated economic benefit was determined by assessing the life of the assets related to the contracts and relationships, likelihood of renewals, competitive factors, regulatory or legal provisions and maintenance costs. The amortization of intangible assets is included in depreciation and amortization expense in our consolidated statements of operations. Intangible assets with finite useful lives are reviewed for impairment when events or
Fair Value Measurements	Fair Value Measurements Fair value measurements are based on a hierarchy which prioritizes the inputs to valuation techniques used to measure fair value into three levels. The fair value hierarchy is as follows: • Level 1 measurements are fair value measurements which use quoted market prices (unadjusted) in active markets for identical assets or liabilities. • Level 2 measurements are fair value measurements which use inputs, other than quoted prices included within Level 1, which are observable for the asset or liability, either directly or indirectly. • Level 3 measurements are fair value measurements which use unobservable inputs. We measure assets and liabilities requiring fair value presentation and disclose such amounts according to the quality of valuation inputs under the fair value hierarchy. The carrying amounts of our cash and cash equivalents, accounts receivable and accounts payable approximate fair value due to the short-term nature and maturity of the instruments and use Level 1 inputs. Our revolving credit facility and term loan credit facilities are variable-rate, non-public debt. The fair value of our revolving credit facility and term loan credit facilities is equivalent to the carrying amount. The fair value is estimated based on significant other observable inputs. As such, we consider the fair value of these facilities to be a Level 2 measurement on the fair value hierarchy. See Note . The fair value of the intangible assets was calculated using the multi-period excess earnings method under the income approach for the existing customers. This valuation method is based on first forecasting gross profit for the existing customers and then applying expected attrition rates. The operating cash flows were calculated by determining the costs required to generate gross profit from the existing customers. The key assumptions include overall gross profit growth, attrition rate of existing customers over time and the discount rate. As the fair value is based on inputs that are not observable in the market, these represent Level 3 inputs. See Note . Certain assets and liabilities, such as property, plant, and equipment, investments, and other intangible assets, are not required to be measured at fair value on a recurring basis. However, these assets are assessed for impairment, and a resulting impairment would require the asset be recorded at fair value.
Transactions With Affiliates	Transactions with Affiliates
Unit-Based Compensation	Unit-Based Compensation
Litigation and Other Contingencies	Litigation and Other Contingencies
Leases	Leases In the normal course of business, we enter into lease agreements to support our operations. We lease field equipment as well as water and pipeline transportation assets. Operating Leases Our operating leases consist of field equipment and transportation assets. Our field equipment leases have fixed monthly payments over a minimum term with options to extend the rental period on a month-to-month basis. Our leased transportation assets have variable monthly payments (price per barrel throughput) over a minimum term with the option to extend on a year-to-year basis. Our operating and variable lease expense is recorded in direct operating expense in our consolidated statement of operations and was de minimis for the year ended December 31, 2020. Finance Leases We lease water assets for use in the performance of our fresh water delivery services. The amount of the lease obligation is based on the discounted present value of future minimum lease payments, and therefore does not reflect future cash lease payments. Our finance lease expense is recorded in depreciation and amortization expense in our consolidated statement of operations and was de minimis for the year ended December 31, 2020. Interest expense for our finance lease is recorded in interest expense in our consolidated statement of operations and was de minimis for the year ended December 31, 2020. Short-Term Leases Leases with an initial term of 12 months or less are not recorded on the balance sheet; we recognize lease expense for these leases on a straight-line basis over the lease term. Short-term lease expense is recorded in direct operating expense in our consolidated statement of operations and was de minimis for the year ended December 31, 2020.
Revenue Recognition	Revenue Recognition We generate revenues by charging fees on a per unit basis for gathering crude oil and natural gas, delivering and storing fresh water, and collecting, cleaning and disposing of produced water. Also, we purchase crude oil from producers and sell crude oil to customers at various delivery points. We adopted ASC 606 on January 1, 2018, using the modified retrospective method. Under ASC 606, performance obligations are the unit of account and generally represent distinct goods or services that are promised to customers. The adoption of ASC 606 did not have an impact on the recognition, measurement and presentation of our revenues and expenses. See Note for disaggregation of revenue by reportable segment. Performance Obligations For gathering crude oil and natural gas, treating crude oil, processing natural gas, delivering and storing fresh water, and collecting, cleaning and disposing of produced water, our performance obligations are satisfied over time using volumes delivered to measure progress. We record revenue related to the volumes delivered at the contract price at the time of delivery. We began generating revenue from crude oil sales during first quarter 2018 upon closing of the Black Diamond Acquisition. An affiliate of Black Diamond engages in the purchase and sale of crude oil. For our crude oil sales, each unit sold is generally considered a distinct good and the related performance obligation is generally satisfied at a point in time (i.e. at the time control of the crude oil is transferred to the customer). We recognize revenue from the sale of crude oil when our contracted performance obligation to deliver crude oil is satisfied and control of the crude oil is transferred to the customer. This usually occurs when the crude oil is delivered to the location specified in the contract and the title and risks of rewards and ownership are transferred to the customer. Transaction Price Allocated to Remaining Performance Obligations Revenues expected to be recognized from certain performance obligations that are unsatisfied as of December 31, 2020 amount to $37.6 million. We have utilized the practical expedients in ASC 606, which state that we are not required to disclose the transaction price allocated to remaining performance obligations if the variable consideration is allocated entirely to a wholly unsatisfied performance obligation or the transaction price allocated to remaining performance obligations if the performance obligation is part of an agreement that has an original expected duration of one year or less. Contract Balances Under our revenue agreements, we invoice customers after our performance obligations have been satisfied, at which point payment is unconditional. As such, our revenue agreements do not give rise to contract assets or liabilities under ASC 606. The following is a summary of our types of revenue agreements: Crude Oil Gathering Under our crude oil gathering agreements, we receive a volumetric fee per barrel (“Bbl”) for the crude oil gathering services we provide. Natural Gas Gathering Under our natural gas gathering agreements, we receive a fee per the contracted unit of measure for the natural gas gathering services we provide. Natural Gas Processing Under our natural gas gathering agreements, we receive a fee per million British Thermal Units (“MMBtu”) for the natural gas processing services we provide. Natural Gas Compression Under our natural gas compression agreements, we receive a volumetric fee per thousand cubic feet (“Mcf”) for the natural gas compression services we provide. Produced Water Services Under our produced water services agreements, we receive a fee for collecting, cleaning or otherwise disposing of water produced from operating crude oil and natural gas wells in the dedication area. The fee is comprised of a volumetric component for services we provide directly and a pass through component for services we provide through contracts with third parties. Fresh Water Services Under our fresh water services agreements, we receive a fee for delivering fresh water. The fee is comprised of a volumetric component for services we provide directly and a pass through component for services we provide through contracts with third parties. The cost of storing the fresh water is included in the delivery fee. Crude Oil Treating Under our crude oil treating agreements, we receive a monthly fee for the crude oil treating services we provide based on each well operated by Noble that is producing in paying quantities that is not connected to our crude oil gathering systems during such month. Crude Oil Purchase and Sale Under our commodity purchase and sale agreements, we purchase crude oil from producers and sell crude oil to customers at various delivery points. For purchase and sale transactions with the same counterparty, the purchase and sale is settled at the contractual price index on a net basis. We account for these transactions on a net basis, in accordance with ASC 845, Non-Monetary Exchanges . We record the residual fee as gathering revenue in our consolidated statements of operations. For purchase and sale transactions with different counterparties, we purchase the crude oil at market-based prices and sell the crude oil to a different counterparty at market-based prices. Market-based pricing is based on the price index applicable for the location of the sale. We account for these transactions on a gross basis.
Recently Adopted and Issued Accounting Standards	Recently Adopted Accounting Standards Clarifying Certain Accounting Standards Codification (“ASC”) Topics In first quarter 2020, the FASB issued ASU No. 2020-01: Investments - Equity Securities (Topic 321), Investments - Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815), to clarify the interactions between these Topics. The update provides clarifications for entities investing in equity securities accounted for under the ASC 321 measurement alternative and companies that hold certain non-derivative forward contracts and purchased options to acquire equity securities. ASU 2020-01 is effective for fiscal years beginning after December 15, 2020, with early adoption permitted. We early adopted this ASU in first quarter 2020. This adoption did not have a material impact on our financial statements. Recently Issued Accounting Standards LIBOR Reform In first quarter 2020, the FASB issued ASU No. 2020-04 (ASU 2020-04): Reference Rate Reform (Topic 848), which provides optional guidance for a limited period of time to ease the transition from LIBOR to an alternative reference rate. The ASU intends to address certain concerns stakeholders raised relating to accounting for contract modifications and hedge accounting. These optional expedients and exceptions to applying GAAP, assuming certain criteria are met, are allowed through December 31, 2022. We are currently evaluating the provisions of ASU 2020-04 and have not yet determined whether we will elect the optional expedients. We do not expect the transition to an alternative rate to have a significant impact on our business, operations or liquidity.

Organization and Nature of Op_2

Organization and Nature of Operations (Tables)	12 Months Ended
	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Subsidiaries	Our assets consist of ownership interests in certain companies which serve specific areas and integrated IDP areas and consist of the following: Company Areas Served NBLX Dedicated Service NBLX Ownership Noncontrolling Interest (1) Colorado River LLC Crude Oil Gathering 100% N/A San Juan River LLC East Pony IDP (DJ Basin) Water Services 100% N/A Green River DevCo LLC Mustang IDP (DJ Basin) Crude Oil Gathering 100% N/A Laramie River LLC Greeley Crescent IDP (DJ Basin) Crude Oil Gathering 100% N/A Black Diamond Dedication Area (DJ Basin) (2) Crude Oil Gathering 54.4% 45.6% Gunnison River DevCo LP Bronco IDP (DJ Basin) (3) Crude Oil Gathering 5% 95% Blanco River LLC Delaware Basin Crude Oil Gathering 100% N/A Trinity River DevCo LLC (4) Delaware Basin Crude Oil Transmission 100% N/A Dos Rios DevCo LLC (5) Delaware Basin Crude Oil Transmission 100% N/A NBL Midstream Holdings LLC East Pony IDP (DJ Basin) Natural Gas Gathering 100% N/A Delaware Basin Crude Oil Gathering 100% N/A (1) The noncontrolling interest represents Noble’s retained ownership interest in the Gunnison River DevCo LP. The noncontrolling interest in Black Diamond represents Greenfield Member’s interest in Black Diamond. (2) Our ownership interest in Saddlehorn is owned through a wholly-owned subsidiary of Black Diamond. See Note . (3) The Bronco IDP area is a future development area. We currently have no midstream infrastructure assets in the Bronco IDP area. (4) Our interest in Advantage is owned through Trinity River DevCo LLC. (5) Our ownership interests in Delaware Crossing, EPIC Crude, EPIC Y-Grade and EPIC Propane are owned through wholly-owned subsidiaries of Dos Rios DevCo LLC. See Note .

Summary of Significant Accoun_3

Summary of Significant Accounting Policies and Basis of Presentation (Tables)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Schedule of Cash, Cash Equivalents	We define total cash as cash, cash equivalents and restricted cash. The following table provides a reconciliation of total cash: Year Ended December 31, (in thousands) 2020 2019 2018 Cash and Cash Equivalents at Beginning of Period $ 12,676 $ 14,761 $ 20,090 Restricted Cash at Beginning of Period (1) (2) 50 951 37,505 Cash, Cash Equivalents, and Restricted Cash at Beginning of Period $ 12,726 $ 15,712 $ 57,595 Cash and Cash Equivalents at End of Period $ 16,332 $ 12,676 $ 14,761 Restricted Cash at End of Period (2) — 50 951 Cash, Cash Equivalents, and Restricted Cash at End of Period $ 16,332 $ 12,726 $ 15,712 (1) Greenfield Member contributed approximately $18.8 million of the amount held in escrow at December 31, 2017 for the Black Diamond Acquisition. (2) Restricted cash represents the amount held as collateral at December 31, 2018 for certain of our letters of credit.
Schedule of Restricted Cash	We define total cash as cash, cash equivalents and restricted cash. The following table provides a reconciliation of total cash: Year Ended December 31, (in thousands) 2020 2019 2018 Cash and Cash Equivalents at Beginning of Period $ 12,676 $ 14,761 $ 20,090 Restricted Cash at Beginning of Period (1) (2) 50 951 37,505 Cash, Cash Equivalents, and Restricted Cash at Beginning of Period $ 12,726 $ 15,712 $ 57,595 Cash and Cash Equivalents at End of Period $ 16,332 $ 12,676 $ 14,761 Restricted Cash at End of Period (2) — 50 951 Cash, Cash Equivalents, and Restricted Cash at End of Period $ 16,332 $ 12,726 $ 15,712 (1) Greenfield Member contributed approximately $18.8 million of the amount held in escrow at December 31, 2017 for the Black Diamond Acquisition. (2) Restricted cash represents the amount held as collateral at December 31, 2018 for certain of our letters of credit.

Transactions with Affiliates (T

Transactions with Affiliates (Tables)	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Schedule of Related Party Transactions	Revenues generated from commercial agreements with Noble consist of the following: Year Ended December 31, (in thousands) 2020 2019 2018 Gathering and Processing $ 328,411 $ 337,086 $ 265,505 Fresh Water Delivery 57,834 77,566 69,266 Other 2,947 3,183 3,976 Total Midstream Services — Affiliate $ 389,192 $ 417,835 $ 338,747
Schedule of General and Administrative Expenses	General and administrative expense consists of the following: Year Ended December 31, (in thousands) 2020 2019 2018 General and Administrative Expense — Affiliate $ 14,957 $ 8,523 $ 8,846 General and Administrative Expense — Third Party 9,764 17,254 17,064 Total General and Administrative Expense $ 24,721 $ 25,777 $ 25,910

Offerings and Acquisition (Tabl

Offerings and Acquisition (Tables)	12 Months Ended
	Dec. 31, 2020
Business Combinations [Abstract]
Reconciliation of Redeemable Noncontrolling Interest Balance	Year Ended December 31, (in thousands) 2020 2019 Redeemable Noncontrolling Interest, Beginning Balance $ 106,005 $ — Preferred Equity Issuance — 100,000 Issuance Costs — (3,435) Preferred Equity Accretion (1) 13,653 9,440 Redeemable Noncontrolling Interest, Ending Balance $ 119,658 $ 106,005 (1) Includes dividends paid-in-kind of approximately $7.0 million and $5.0 million for the years ended December 31, 2020 and 2019, respectively. The dividend for each quarter in 2019 and 2020 was paid-in-kind.
Schedule of Business Acquisitions, by Acquisition	The following table sets forth our purchase price allocation: (in thousands) Cash Consideration $ 638,266 PDC Energy Payment 24,120 Current Liabilities Assumed 18,259 Total Purchase Price and Liabilities Assumed $ 680,645 Cash and Restricted Cash $ 12,518 Accounts Receivable 10,661 Other Current Assets 2,206 Property, Plant and Equipment 205,766 Intangible Assets (1) 339,760 Fair Value of Identifiable Assets 570,911 Implied Goodwill (2) 109,734 Total Asset Value $ 680,645 (1) See Note . (2) Recognized goodwill was assigned to the Black Diamond reporting unit within the Gathering Systems reportable segment. This amount was fully impaired in first quarter 2020.

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, plant and equipment, at cost, is as follows: (in thousands) December 31, 2020 December 31, 2019 Gathering and Processing Systems $ 1,924,125 $ 1,795,957 Fresh Water Delivery Systems (1) 95,849 96,004 Construction-in-Progress (2) 54,816 115,034 Total Property, Plant and Equipment, at Cost 2,074,790 2,006,995 Accumulated Depreciation and Amortization (315,441) (244,038) Property, Plant and Equipment, Net $ 1,759,349 $ 1,762,957 (1) Fresh water delivery system assets at December 31, 2020 and December 31, 2019 include $5.0 million related to a leased pond accounted for as a finance lease. See Note .

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2020
Investments, All Other Investments [Abstract]
Summary of Investments	The following table presents our investments at the dates indicated: (in thousands) December 31, 2020 December 31, 2019 White Cliffs $ 10,204 $ 10,268 Advantage (1) 72,500 76,834 Delaware Crossing 81,476 68,707 EPIC Crude 373,623 339,116 EPIC Y-Grade 194,188 162,850 EPIC Propane 12,905 3,003 Saddlehorn (2) 160,059 — Total Investments (3) $ 904,955 $ 660,778 (1) Distributions from Advantage totaled $12.0 million and $10.1 million during the years ended December 31, 2020 and 2019, respectively. (2) Distributions from Saddlehorn totaled $25.0 million during the year ended December 31, 2020. (3) We have capitalized $33.8 million in expenses that are included in the basis of the investments. The capitalized items include acquisition related expenses and capitalized interest. Unamortized capitalized expenses totaled $32.8 million and $27.7 million as of December 31, 2020 and December 31, 2019, respectively.
Schedule of Investment Loss (Income)	The following table presents our investment loss (income) for the periods indicated: Year Ended December 31, (in thousands) 2020 2019 2018 White Cliffs $ (1,844) $ (3,107) $ (3,687) Advantage (6,103) (8,159) (11,880) Delaware Crossing 3,390 3,061 — EPIC Crude 26,663 19,152 — EPIC Y-Grade 38,425 8,381 — EPIC Propane 300 — — Saddlehorn (24,199) — — Other (1) (1,741) (1,580) (722) Total Investment Loss (Income) $ 34,891 $ 17,748 $ (16,289) (1) Represents our fee for serving as the operator of Advantage and Delaware Crossing.
Summary of Equity Method Investments	Summarized, 100% combined balance sheet information for equity method investments was as follows: (in thousands) December 31, 2020 December 31, 2019 Current Assets $ 427,337 $ 304,057 Noncurrent Assets 5,261,349 4,296,648 Current Liabilities 329,779 443,573 Noncurrent Liabilities 2,099,429 1,868,138 Summarized, 100% combined statements of operations for equity method investments was as follows: Year Ended December 31, (in thousands) 2020 2019 2018 Operating Revenues $ 760,925 $ 481,466 $ 35,153 Operating Expenses 878,579 575,306 11,148 Operating (Loss) Income (117,654) (93,840) 24,005 Other Expense (Income) 147,128 41,616 (37) (Loss) Income Before Income Taxes (264,782) (135,456) 24,042 Tax Expense 96 118 171 Net (Loss) Income $ (264,878) $ (135,574) $ 23,871

Intangible Assets (Tables)

Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets	Our intangible assets are as follows: December 31, 2020 December 31, 2019 (in thousands) Gross Accumulated Amortization (1) Net Gross Accumulated Amortization (1) Net Customer Contracts and Relationships $ 339,760 $ 94,250 $ 245,510 $ 339,760 $ 61,860 $ 277,900 (1) For the years ended December 31, 2020 and 2019, amortization expense related to intangible assets totaled $32.4 million and $32.3 million, respectively.
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	Estimated future amortization expense related to the intangible assets at December 31, 2020 is as follows: (in thousands) December 31, 2020 2021 $ 32,301 2022 32,301 2023 32,301 2024 32,390 2025 27,871 Thereafter 88,346 Total $ 245,510

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Long-term debt as of December 31, 2020 and December 31, 2019 was as follows: December 31, 2020 December 31, 2019 (in thousands, except percentages) Debt Interest Rate Debt Interest Rate Revolving Credit Facility, due March 9, 2023 $ 710,000 1.61 % $ 595,000 3.11 % 2018 Term Loan Credit Facility, due July 31, 2021 500,000 1.36 % 500,000 2.85 % 2019 Term Loan Credit Facility, due August 23, 2022 400,000 1.24 % 400,000 2.74 % Finance Lease Obligation (1) 2,063 — % 2,005 — % Total 1,612,063 1,497,005 Term Loan Credit Facilities Unamortized Debt Issuance Costs (555) (1,326) Total Debt 1,611,508 1,495,679 Less Amounts Due Within One Year 2018 Term Loan Credit Facility, due July 31, 2021, Net (499,793) — Finance Lease Obligation (1) (2,063) — Long-Term Debt $ 1,109,652 $ 1,495,679 (1) See Note and Note .

Asset Retirement Obligations (T

Asset Retirement Obligations (Tables)	12 Months Ended
	Dec. 31, 2020
Asset Retirement Obligation Disclosure [Abstract]
Schedule of Change in Asset Retirement Obligation	Changes in AROs are as follows: Year Ended December 31, (in thousands) 2020 2019 Asset Retirement Obligations, Beginning Balance $ 37,842 $ 30,533 Liabilities Incurred 657 1,912 Liabilities Settled (46) (131) Revision of Estimate 1,380 3,686 Accretion Expense (1) 1,739 1,842 Asset Retirement Obligations, Ending Balance $ 41,572 $ 37,842 (1) Accretion expense is included in depreciation and amortization expense in the consolidated statements of operations.

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	Summarized financial information concerning our reportable segments is as follows: (in thousands) Gathering Systems Fresh Water Delivery Investments in Midstream Entities Corporate (1) Consolidated Year Ended December 31, 2020 Midstream Services — Affiliate $ 331,358 $ 57,834 $ — $ — $ 389,192 Midstream Services — Third Party 86,548 7,680 — — 94,228 Crude Oil Sales — Third Party 281,205 — — — 281,205 Total Revenues 699,111 65,514 — — 764,625 Cost of Crude Oil Sales 270,678 — — — 270,678 Direct Operating Expense 80,214 8,663 — 3,510 92,387 Depreciation and Amortization 102,784 2,913 — — 105,697 Goodwill Impairment 109,734 — — — 109,734 Income (Loss) Before Income Taxes 131,003 53,939 (34,891) (54,802) 95,249 Year Ended December 31, 2019 Midstream Services — Affiliate $ 340,269 $ 77,566 $ — $ — $ 417,835 Midstream Services — Third Party 83,603 12,591 — — 96,194 Crude Oil Sales — Third Party 189,772 — — — 189,772 Total Revenues 613,644 90,157 — — 703,801 Cost of Crude Oil Sales 181,390 — — — 181,390 Direct Operating Expense 95,743 18,650 — 2,282 116,675 Depreciation and Amortization 94,455 2,526 — — 96,981 Income (Loss) Before Income Taxes 242,545 68,980 (17,748) (44,295) 249,482 Year Ended December 31, 2018 Midstream Services — Affiliate $ 269,481 $ 69,266 $ — $ — $ 338,747 Midstream Services — Third Party 59,153 19,345 — — 78,498 Crude Oil Sales — Third Party 141,490 — 141,490 Total Midstream Services Revenues 470,124 88,611 — — 558,735 Direct Operating Expense 79,848 14,269 — 1,735 95,852 Depreciation and Amortization 77,309 2,259 — — 79,568 Income (Loss) Before Income Taxes 172,826 72,083 16,289 (36,478) 224,720 December 31, 2020 Intangible Assets, Net $ 245,510 $ — $ — $ — $ 245,510 Goodwill — — — — — Total Assets 2,014,935 105,599 904,955 11,707 3,037,196 Additions to Long-Lived Assets 70,118 — 317,229 523 387,870 December 31, 2019 Intangible Assets, Net $ 277,900 $ — $ — $ — $ 277,900 Goodwill 109,734 — — — 109,734 Total Assets 2,160,026 91,840 660,778 13,438 2,926,082 Additions to Long-Lived Assets 257,066 7,330 611,325 1,068 876,789 (1) The Corporate segment includes all general Partnership activity not attributable to our operating subsidiaries.

Unit-Based Compensation (Tables

Unit-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Share-based Compensation, Activity	Restricted unit activity for the year ended December 31, 2020 was as follows: Number of Units Weighted Average Award Date Fair Value Awarded and Unvested Units at December 31, 2019 103,355 $ 36.04 Awarded 145,731 22.40 Vested (48,809) 36.41 Forfeited (27,194) 25.92 Awarded and Unvested Units at December 31, 2020 173,083 $ 26.04

Partnership Distributions (Tabl

Partnership Distributions (Tables)	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Distributions Made to Limited Partner, by Distribution	The following table details the distributions paid in respect of the periods presented below: Distributions (in thousands except per unit amounts) Limited Partners Period Record Date Distribution Date Distribution per Limited Partner Unit Common Unitholders (1) Subordinated Unitholders (2) Holder of IDRs (3) Total Q4 2017 February 5, 2018 February 12, 2018 $ 0.4883 $ 11,566 $ 7,765 $ 520 $ 19,851 Q1 2018 May 7, 2018 May 14, 2018 0.5110 12,103 8,126 819 21,048 Q2 2018 August 6, 2018 August 13, 2018 0.5348 12,668 8,504 1,134 22,306 Q3 2018 November 5, 2018 November 13, 2018 0.5597 13,258 8,901 1,462 23,621 Q4 2018 February 4, 2019 February 11, 2019 0.5858 13,876 9,316 2,421 25,613 Q1 2019 May 6, 2019 May 13, 2019 0.6132 14,534 9,751 3,507 27,792 Q2 2019 August 5, 2019 August 12, 2019 0.6418 25,418 — 4,640 30,058 Q3 2019 November 4, 2019 November 12, 2019 0.6716 26,598 — 5,820 32,418 Q4 2019 February 4, 2020 February 14, 2020 0.6878 62,012 — — 62,012 Q1 2020 May 8, 2020 May 15, 2020 0.1875 16,906 — — 16,906 Q2 2020 August 7, 2020 August 14, 2020 0.1875 16,907 — — 16,907 Q3 2020 November 6, 2020 November 13, 2020 0.1875 16,907 — — 16,907 (1) Distributions to common unitholders do not include distribution equivalent rights on units that vested under the LTIP. (2) See Conversion of Subordinated Units, below. (3) In November 2019, we acquired all of Noble ’s IDRs. See Note 3. Transactions with Affiliates .

Net Income Per Limited Partne_2

Net Income Per Limited Partner Unit (Tables)	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	Our calculation of net income per limited partner Common and Subordinated Unit is as follows: Year Ended December 31, (in thousands) 2020 2019 2018 Net Income Attributable to Noble Midstream Partners LP $ 134,031 $ 159,996 $ 162,734 Less: Net Income Attributable to Incentive Distribution Rights — 13,967 5,836 Net Income Attributable to Limited Partners $ 134,031 $ 146,029 $ 156,898 Net Income Allocable to Common Units $ 134,031 $ 123,662 $ 93,875 Net Income Allocable to Subordinated Units — 22,367 63,023 Net Income Attributable to Limited Partners $ 134,031 $ 146,029 $ 156,898 Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic Common Units $ 1.49 $ 3.09 $ 3.96 Subordinated Units $ — $ 3.86 $ 3.96 Net Income Attributable to Limited Partners Per Limited Partner Unit — Diluted Common Units $ 1.49 $ 3.08 $ 3.96 Subordinated Units $ — $ 3.86 $ 3.96 Weighted Average Limited Partner Units Outstanding — Basic Common Units 90,165 40,083 23,686 Subordinated Units — 5,795 15,903 Weighted Average Limited Partner Units Outstanding — Diluted Common Units 90,167 40,105 23,701 Subordinated Units — 5,795 15,903 Antidilutive Restricted Units 184 54 24

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Schedule of Minimum Commitments	Minimum commitments as of December 31, 2020 are as follows: (in thousands) Future Minimum Finance Lease Payments Future Minimum Operating Lease Payments Purchase Obligations (1) Transportation Fees (2) Surface Lease Obligations Total 2021 $ 2,063 $ 260 $ 2,064 $ 34,101 $ 217 $ 38,705 2022 — — — 34,195 176 34,371 2023 — — — 34,879 176 35,055 2024 — — — 35,954 176 36,130 2025 — — — 36,576 176 36,752 2026 and Beyond — — — 26,072 3,698 29,770 Total $ 2,063 $ 260 $ 2,064 $ 201,777 $ 4,619 $ 210,783 (1) Purchase obligations represent contractual agreements to purchase goods or services that are enforceable, are legally binding and specify all significant terms, including fixed and minimum quantities to be purchased; fixed, minimum or variable price provisions; and the approximate timing of the transaction. (2) We have entered into long-term agreements with unaffiliated third parties to satisfy a substantial portion of our transportation commitment.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	The following table presents our tax provision for the periods indicated: Year Ended December 31, (in thousands) 2020 2019 2018 Current $ (161) $ 541 $ 1,323 Deferred 544 3,474 6,678 Tax Provision (1) $ 383 $ 4,015 $ 8,001 Effective Tax Rate 0.4 % 1.6 % 3.6 %

Supplemental Quarterly Financ_2

Supplemental Quarterly Financial Information (Tables)	12 Months Ended
	Dec. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information	Supplemental quarterly financial information is as follows: (in thousands except per share amounts) First Quarter Second Quarter Third Quarter Fourth Quarter Year Ended December 31, 2020 Total Revenues $ 224,045 $ 145,950 $ 187,365 $ 207,265 Operating Income (25,101) 61,431 62,071 58,309 Income Before Income Taxes (37,367) 50,732 38,902 42,982 Net Income (37,516) 50,860 38,736 42,786 Net Income Attributable to Limited Partners 10,103 48,236 35,784 39,908 Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic Common Units $ 0.11 $ 0.53 $ 0.40 $ 0.44 Year Ended December 31, 2019 Total Revenues $ 160,702 $ 170,660 $ 181,674 $ 190,765 Operating Income 71,987 60,564 81,271 69,644 Income Before Income Taxes 69,100 56,494 71,698 52,190 Net Income 67,791 55,763 70,519 51,394 Net Income Attributable to Limited Partners 40,052 31,769 34,812 39,396 Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic Common Units $ 1.01 $ 0.79 $ 0.88 $ 0.65 Subordinated Units 1.01 0.84 — —

Organization and Nature of Op_3

Organization and Nature of Operations - Narrative (Details) - $ / shares	3 Months Ended	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2020	Feb. 04, 2021
Common Units | Subsequent Event
Subsidiary of Limited Liability Company or Limited Partnership
Sale of stock price (in usd per share)			$ 12.47
Noble | Noble
Subsidiary of Limited Liability Company or Limited Partnership
Initial term		15 years
Chevron | Noble Midstream Partners LP
Subsidiary of Limited Liability Company or Limited Partnership
NBLX Ownership	62.60%

Organization and Nature of Op_4

Organization and Nature of Operations - Summary of Partnership Assets (Details)	12 Months Ended
	Dec. 31, 2020
Colorado River LLC
Subsidiary of Limited Liability Company or Limited Partnership
NBLX Ownership	100.00%
San Juan River LLC
Subsidiary of Limited Liability Company or Limited Partnership
NBLX Ownership	100.00%
Green River DevCo LLC
Subsidiary of Limited Liability Company or Limited Partnership
NBLX Ownership	100.00%
Laramie River LLC | Greeley Crescent IDP (DJ Basin)
Subsidiary of Limited Liability Company or Limited Partnership
NBLX Ownership	100.00%
Laramie River LLC | Black Diamond Dedication Area (DJ Basin)
Subsidiary of Limited Liability Company or Limited Partnership
NBLX Ownership	54.40%
Noncontrolling interest	45.60%
Gunnison River DevCo LP
Subsidiary of Limited Liability Company or Limited Partnership
NBLX Ownership	5.00%
Noncontrolling interest	95.00%
Blanco River LLC
Subsidiary of Limited Liability Company or Limited Partnership
NBLX Ownership	100.00%
Trinity River DevCo LLC
Subsidiary of Limited Liability Company or Limited Partnership
NBLX Ownership	100.00%
Dos Rios DevCo LLC
Subsidiary of Limited Liability Company or Limited Partnership
NBLX Ownership	100.00%
NBL Midstream Holdings LLC | East Pony IDP (DJ Basin)
Subsidiary of Limited Liability Company or Limited Partnership
NBLX Ownership	100.00%
NBL Midstream Holdings LLC | Delaware Basin
Subsidiary of Limited Liability Company or Limited Partnership
NBLX Ownership	100.00%

Summary of Significant Accoun_4

Summary of Significant Accounting Policies and Basis of Presentation - Narrative (Details) $ in Thousands	Mar. 25, 2019	Apr. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Jul. 31, 2020USD ($)	Dec. 31, 2017USD ($)
Concentration Risk
Internal rate of return on preferred stock				12.00%
Preferred stock, redemption price multiplier				1.375
Preferred equity, dividend rate	6.50%			6.50%
Unpaid dividend accrual term				2 years
Capitalized interest				$ 5,500	$ 17,500	$ 6,400
Property plant and equipment useful life (years)				29 years
Impairment of long-lived assets						1,000
Goodwill Impairment			$ 109,700	$ 109,734	0	0
Due from related party				55,011	42,428
Accrued capital expenditures				12,500	56,600	72,600
Interest paid				31,300	33,000	$ 16,300
Elimination of deferred tax asset					26,000
Elimination of current tax liability					$ 2,900
Remaining performance obligations				$ 37,600
Greenfield Member
Concentration Risk
Escrow deposit								$ 18,800
EPIC Y-Grade
Concentration Risk
Payments to acquire loans receivable		$ 22,500
Due from related party							$ 23,400
Revenue | Customer Concentration Risk | Third Party
Concentration Risk
Concentration risk				15.00%		17.00%
Revenue | Customer Concentration Risk | Third Party | Crude Oil Sales
Concentration Risk
Concentration risk				40.00%		66.00%
Noble | Revenue | Customer Concentration Risk | Noble and Affiliates
Concentration Risk
Concentration risk				81.00%	59.00%	61.00%
Noble | Revenue | Customer Concentration Risk | Noble and Affiliates | Midstream Services
Concentration Risk
Concentration risk				51.00%	81.00%	81.00%
Gathering Systems
Concentration Risk
Impairment of long-lived assets						$ 3,500
Insurance recoveries						$ 2,500

Summary of Significant Accoun_5

Summary of Significant Accounting Policies and Basis of Presentation - Summary of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Cash and Cash Equivalents		$ 16,332	$ 12,676	$ 14,761	$ 20,090
Restricted Cash		0	50	951	37,505
Cash, Cash Equivalents and Restricted Cash	[1]	$ 16,332	$ 12,726	$ 15,712	$ 57,595
[1]	See Note 2. Summary of Significant Accounting Policies and Basis of Presentation for our reconciliation of total cash.

Summary of Significant Accoun_6

Summary of Significant Accounting Policies and Basis of Presentation - Remaining Performance Obligations (Details)	Dec. 31, 2020
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction
Remaining performance obligations, expected timing of satisfaction	1 year

Transactions with Affiliates -

Transactions with Affiliates - Narrative (Details) - USD ($)	Nov. 14, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Mar. 01, 2021	Mar. 01, 2020
Related Party Transaction
Annual cap rate						$ 15,700,000
Subsequent Event
Related Party Transaction
Annual cap rate					$ 18,000,000
Capital Project Costs
Related Party Transaction
Related party expenses		$ 5,400,000	$ 6,600,000	$ 7,200,000
Operational Employee Costs
Related Party Transaction
Related party expenses		$ 16,600,000	$ 16,300,000	$ 13,900,000
Blanco River LLC | Noble
Related Party Transaction
Interest in partnership	60.00%
Green River DevCo LLC | Noble
Related Party Transaction
Interest in partnership	75.00%
San Juan River LLC | Noble
Related Party Transaction
Interest in partnership	75.00%
Blanco River And Colorado River DevCos | Noble
Related Party Transaction
Consideration transferred	$ 1,600,000,000
Payments to acquire businesses	$ 670,000,000
Equity interest issued (shares)	38,455,018
Noble | Noble
Related Party Transaction
Initial term		15 years
Renewal term		1 year

Transactions with Affiliates _2

Transactions with Affiliates - Revenue from Affiliates (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction
Total Midstream Services — Affiliate	$ 389,192	$ 417,835	$ 338,747
Noble | Noble
Related Party Transaction
Total Midstream Services — Affiliate	389,192	417,835	338,747
Noble | Noble | Gathering and Processing
Related Party Transaction
Total Midstream Services — Affiliate	328,411	337,086	265,505
Noble | Noble | Fresh Water Delivery
Related Party Transaction
Total Midstream Services — Affiliate	57,834	77,566	69,266
Noble | Noble | Other
Related Party Transaction
Total Midstream Services — Affiliate	$ 2,947	$ 3,183	$ 3,976

Transactions with Affiliates _3

Transactions with Affiliates - Expenses with Transaction with Affiliates (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transactions [Abstract]
General and Administrative Expense — Affiliate	$ 14,957	$ 8,523	$ 8,846
General and Administrative Expense — Third Party	9,764	17,254	17,064
Total General and Administrative Expense	$ 24,721	$ 25,777	$ 25,910

Offerings and Acquisition - Nar

Offerings and Acquisition - Narrative (Details) $ / shares in Units, a in Thousands	Nov. 14, 2019USD ($)shares	Mar. 25, 2019USD ($)$ / sharesshares	Jan. 31, 2018USD ($)aMMBTUmi	Dec. 31, 2018USD ($)	Dec. 31, 2020	Dec. 31, 2018USD ($)
Business Acquisition
Proceeds from private placement, gross	$ 250,000,000
Proceeds from private placement, net	$ 242,900,000
Equity commitment amount		$ 200,000,000
Preferred units issued (in units) | shares		100,000
Face value per unit (in usd per unit) | $ / shares		$ 1,000
Proceeds from issuance		$ 100,000,000
Preferred equity, dividend rate		6.50%			6.50%
Remaining equity commitment		$ 100,000,000
Black Diamond Gathering LLC
Business Acquisition
Interest acquired			54.40%
Ownership promote			4.40%
Black Diamond Gathering LLC
Business Acquisition
Payment to expand acreage dedication			$ 24,100,000
Increase in duration of the acreage dedication			5 years
Black Diamond Acquisition
Business Acquisition
Dedicated acres | a			141
Acquisition related costs						$ 6,800,000
Greenfield Member | Black Diamond Gathering LLC
Business Acquisition
Interest acquired			45.60%
Black Diamond Acquisition
Business Acquisition
Payments to acquire businesses			$ 638,500,000
Length (miles) | mi			160
Delivery capacity (Mbbl/day) | MMBTU			300
Revenue since acquisition				$ 181,200,000
Pre-tax net loss since acquisition				$ 11,500,000
Black Diamond Acquisition | Black Diamond Gathering LLC
Business Acquisition
Payments to acquire businesses			$ 638,266,000
Payment to expand acreage dedication			24,120,000
Black Diamond Acquisition | Greenfield Member
Business Acquisition
Payments to acquire businesses			318,600,000
Black Diamond Acquisition | Noble Member
Business Acquisition
Payments to acquire businesses			$ 319,900,000
Private Placement
Business Acquisition
Sold (in units) | shares	12,077,295
Payments of stock issuance costs	$ 7,100,000

Offerings and Acquisition - Red

Offerings and Acquisition - Redeemable Noncontrolling Interest Balance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Redeemable Noncontrolling Interest
Redeemable Noncontrolling Interest, Beginning Balance	$ 106,005	$ 0
Preferred Equity Issuance	0	100,000
Issuance Costs	0	(3,435)
Preferred Equity Accretion	13,653	9,440
Redeemable Noncontrolling Interest, Ending Balance	119,658	106,005
Paid-in-kind dividend	$ 7,000	$ 5,000

Offerings and Acquisition - All

Offerings and Acquisition - Allocation of Purchase Price (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition
Implied Goodwill		$ 0	$ 109,734
Black Diamond Acquisition
Business Acquisition
Cash Consideration	$ 638,500
Black Diamond Gathering LLC
Business Acquisition
PDC Energy Payment	24,100
Black Diamond Gathering LLC | Black Diamond Acquisition
Business Acquisition
Cash Consideration	638,266
PDC Energy Payment	24,120
Current Liabilities Assumed	18,259
Total Purchase Price and Liabilities Assumed	680,645
Cash and Restricted Cash	12,518
Accounts Receivable	10,661
Other Current Assets	2,206
Property, Plant and Equipment	205,766
Intangible Assets	339,760
Fair Value of Identifiable Assets	570,911
Implied Goodwill	109,734
Total Asset Value	$ 680,645

Property, Plant and Equipment_2

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment
Total Property, Plant and Equipment, at Cost	$ 2,074,790	$ 2,006,995
Accumulated Depreciation and Amortization	(315,441)	(244,038)
Total Property, Plant and Equipment, Net	1,759,349	1,762,957
Gathering and Processing Systems
Property, Plant and Equipment
Total Property, Plant and Equipment, at Cost	1,924,125	1,795,957
Construction in-progress	43,800	98,400
Fresh Water Delivery System
Property, Plant and Equipment
Total Property, Plant and Equipment, at Cost	95,849	96,004
Capital lease	5,000	5,000
Construction-in-Progress
Property, Plant and Equipment
Total Property, Plant and Equipment, at Cost	54,816	115,034
Equipment Reserved For Future Use
Property, Plant and Equipment
Construction in-progress	$ 9,500	$ 15,400

Investments - Narrative (Detail

Investments - Narrative (Details) $ in Millions	Apr. 03, 2017USD ($)	Feb. 28, 2020USD ($)MMBTU	Dec. 31, 2020USD ($)
White Cliffs
Schedule of Equity Method Investments
Ownership percentage			3.00%
Advantage
Schedule of Equity Method Investments
Equity method investment, ownership percentage			50.00%
Capital contributions	$ 66.8
Delaware Crossing
Schedule of Equity Method Investments
Equity method investment, ownership percentage			50.00%
Capital contributions			$ 14.8
EPIC Crude
Schedule of Equity Method Investments
Equity method investment, ownership percentage			30.00%
Capital contributions			$ 58.5
EPIC Y-Grade
Schedule of Equity Method Investments
Equity method investment, ownership percentage			15.00%
Capital contributions			$ 44.9
EPIC Propane
Schedule of Equity Method Investments
Equity method investment, ownership percentage			15.00%
Capital contributions			$ 10.1
Saddlehorn(2)
Schedule of Equity Method Investments
Ownership percentage			20.00%
Capital contributions		$ 87
Total capacity (Mbbl/day) | MMBTU		290
Saddlehorn(2) | Black Diamond
Schedule of Equity Method Investments
Ownership percentage		10.00%
Saddlehorn(2) | Magellan and Plains
Schedule of Equity Method Investments
Ownership percentage		30.00%
Saddlehorn(2) | Black Diamond and Western Midstream
Schedule of Equity Method Investments
Ownership percentage		20.00%
Saddlehorn(2) | Black Diamond
Schedule of Equity Method Investments
Ownership percentage		20.00%
Capital contributions		$ 160
Plains | Black Diamond
Schedule of Equity Method Investments
Ownership percentage		10.00%
Plains | Magellan and Plains
Schedule of Equity Method Investments
Ownership percentage		30.00%
Western Midstream | Black Diamond and Western Midstream
Schedule of Equity Method Investments
Ownership percentage		20.00%

Investments - Summary of Invest

Investments - Summary of Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule of Equity Method Investments
Investments	$ 904,955	$ 660,778
Distributions	112,880	115,935	$ 86,841
Acquisition related expenses	33,800
Unamortized acquisition related expenses	32,800	27,700
White Cliffs
Schedule of Equity Method Investments
Investments	10,204	10,268
Advantage
Schedule of Equity Method Investments
Investments	72,500	76,834
Distributions	12,000	10,100
Delaware Crossing
Schedule of Equity Method Investments
Investments	81,476	68,707
EPIC Crude
Schedule of Equity Method Investments
Investments	373,623	339,116
EPIC Y-Grade
Schedule of Equity Method Investments
Investments	194,188	162,850
EPIC Propane
Schedule of Equity Method Investments
Investments	12,905	3,003
Saddlehorn(2)
Schedule of Equity Method Investments
Investments	160,059	$ 0
Distributions	$ 25,000

Investments - Investment Income

Investments - Investment Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule of Equity Method Investments
Investment Loss (Income)	$ 34,891	$ 17,748	$ (16,289)
White Cliffs
Schedule of Equity Method Investments
Investment Loss (Income)	(1,844)	(3,107)	(3,687)
Advantage
Schedule of Equity Method Investments
Investment Loss (Income)	(6,103)	(8,159)	(11,880)
Delaware Crossing
Schedule of Equity Method Investments
Investment Loss (Income)	3,390	3,061	0
EPIC Crude
Schedule of Equity Method Investments
Investment Loss (Income)	26,663	19,152	0
EPIC Y-Grade
Schedule of Equity Method Investments
Investment Loss (Income)	38,425	8,381	0
EPIC Propane
Schedule of Equity Method Investments
Investment Loss (Income)	300	0	0
Saddlehorn(2)
Schedule of Equity Method Investments
Investment Loss (Income)	(24,199)	0	0
Other
Schedule of Equity Method Investments
Investment Loss (Income)	$ (1,741)	$ (1,580)	$ (722)

Investments - Equity Method Inv

Investments - Equity Method Investments (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Balance Sheet Information
Current Assets	$ 125,051				$ 107,927				$ 125,051	$ 107,927
Current Liabilities	581,615				127,540				581,615	127,540
Statements of Operations Information
Operating (Loss) Income	58,309	$ 62,071	$ 61,431	$ (25,101)	69,644	$ 81,271	$ 60,564	$ 71,987	156,710	283,466	$ 218,878
Other Expense (Income)									4,698	(488)	2,159
Income (Loss) Before Income Taxes	42,982	38,902	50,732	(37,367)	52,190	71,698	56,494	69,100	95,249	249,482	224,720
Tax Expense									383	4,015	8,001
Net (Loss) Income	42,786	$ 38,736	$ 50,860	$ (37,516)	51,394	$ 70,519	$ 55,763	$ 67,791	94,866	245,467	216,719
Equity Method Investment
Balance Sheet Information
Current Assets	427,337				304,057				427,337	304,057
Noncurrent Assets	5,261,349				4,296,648				5,261,349	4,296,648
Current Liabilities	329,779				443,573				329,779	443,573
Noncurrent Liabilities	$ 2,099,429				$ 1,868,138				2,099,429	1,868,138
Statements of Operations Information
Operating Revenues									760,925	481,466	35,153
Operating Expenses									878,579	575,306	11,148
Operating (Loss) Income									(117,654)	(93,840)	24,005
Other Expense (Income)									147,128	41,616	(37)
Income (Loss) Before Income Taxes									(264,782)	(135,456)	24,042
Tax Expense									96	118	171
Net (Loss) Income									$ (264,878)	$ (135,574)	$ 23,871

Intangible Assets - Summary of

Intangible Assets - Summary of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Gross	$ 339,760	$ 339,760
Accumulated Amortization	94,250	61,860
Total	245,510	277,900
Amortization Expense	$ 32,400	$ 32,300

Intangible Assets - Future Amor

Intangible Assets - Future Amortization Expense (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity
2021	$ 32,301
2022	32,301
2023	32,301
2024	32,390
2025	27,871
Thereafter	88,346
Total	$ 245,510	$ 277,900

Long-Term Debt - Schedule of Lo

Long-Term Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument
Interest Rate	0.00%	0.00%
Finance Lease Obligation	$ 2,063	$ 2,005
Long-Term Debt	1,612,063	1,497,005
Term Loan Credit Facilities Unamortized Debt Issuance Costs	(555)	(1,326)
Long-Term Debt	1,611,508	1,495,679
Less Amounts Due Within One Year
2018 Term Loan Credit Facility, due July 31, 2021, Net	(499,793)	0
Finance Lease Obligation	(2,063)	0
Long-Term Debt	1,109,652	1,495,679
Revolving Credit Facility | Revolving Credit Facility, due March 9, 2023
Debt Instrument
Debt	$ 710,000	$ 595,000
Interest Rate	1.61%	3.11%
Term Loan Credit Facility | 2018 Term Loan Credit Facility, due July 31, 2021
Debt Instrument
Debt	$ 500,000	$ 500,000
Interest Rate	1.36%	2.85%
Term Loan Credit Facility | 2019 Term Loan Credit Facility, due August 23, 2022
Debt Instrument
Debt	$ 400,000	$ 400,000
Interest Rate	1.24%	2.74%

Long-Term Debt - Narrative (Det

Long-Term Debt - Narrative (Details) - USD ($)	Aug. 23, 2019	Jul. 31, 2018	Dec. 31, 2020	Dec. 31, 2019
Revolving Credit Facility
Line of Credit Facility
Available borrowing capacity			$ 440,000,000
Credit facility increased capacity			$ 1,150,000,000
Commitment fee			0.275%	0.275%
Unamortized debt issuance expense			$ 2,100,000	$ 3,000,000
Revolving Credit Facility | Federal Funds Effective Swap Rate
Line of Credit Facility
Basis spread			0.50%
Revolving Credit Facility | London Interbank Offered Rate (LIBOR)
Line of Credit Facility
Basis spread			1.00%
Term Loan Credit Facility
Line of Credit Facility
Maximum borrowing capacity	$ 400,000,000	$ 500,000,000
Debt instrument term	3 years	3 years
Term Loan Credit Facility | Base Rate | Minimum
Line of Credit Facility
Basis spread	0.00%	0.00%
Term Loan Credit Facility | Base Rate | Maximum
Line of Credit Facility
Basis spread	0.375%	0.50%
Term Loan Credit Facility | Eurodollar | Minimum
Line of Credit Facility
Basis spread	0.875%	1.00%
Term Loan Credit Facility | Eurodollar | Maximum
Line of Credit Facility
Basis spread	1.375%	1.50%

Asset Retirement Obligations -

Asset Retirement Obligations - Asset Retirement Obligation Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Asset Retirement Obligation, Roll Forward Analysis
Asset Retirement Obligations, Beginning Balance	$ 37,842	$ 30,533
Liabilities Incurred	657	1,912
Liabilities Settled	(46)	(131)
Revision of Estimate	1,380	3,686
Accretion Expense	1,739	1,842
Asset Retirement Obligations, Ending Balance	$ 41,572	$ 37,842

Segment Information - Summarize

Segment Information - Summarized Financial Results by Segment (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended								12 Months Ended
	Mar. 31, 2020	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information
Midstream Services — Affiliate										$ 389,192	$ 417,835	$ 338,747
Total Revenues		$ 207,265	$ 187,365	$ 145,950	$ 224,045	$ 190,765	$ 181,674	$ 170,660	$ 160,702	764,625	703,801	558,735
Cost of Crude Oil Sales										270,678	181,390	136,368
Direct Operating Expense										92,387	116,675	95,852
Depreciation and Amortization										105,697	96,981	79,568
Goodwill Impairment	$ 109,700									109,734	0	0
Income (Loss) Before Income Taxes		42,982	$ 38,902	$ 50,732	$ (37,367)	52,190	$ 71,698	$ 56,494	$ 69,100	95,249	249,482	224,720
Intangible Assets, Net		245,510				277,900				245,510	277,900
Goodwill		0				109,734				0	109,734
Total Assets		3,037,196				2,926,082				3,037,196	2,926,082
Additions to Long-Lived Assets										387,870	876,789
Midstream Services — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party										94,228	96,194	78,498
Crude Oil Sales — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party										281,205	189,772	141,490
Gathering Systems
Segment Reporting Information
Midstream Services — Affiliate										331,358	340,269	269,481
Total Revenues										699,111	613,644	470,124
Cost of Crude Oil Sales										270,678	181,390
Direct Operating Expense										80,214	95,743	79,848
Depreciation and Amortization										102,784	94,455	77,309
Goodwill Impairment										109,734
Income (Loss) Before Income Taxes										131,003	242,545	172,826
Intangible Assets, Net		245,510				277,900				245,510	277,900
Goodwill		0				109,734				0	109,734
Total Assets		2,014,935				2,160,026				2,014,935	2,160,026
Additions to Long-Lived Assets										70,118	257,066
Gathering Systems | Midstream Services — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party										86,548	83,603	59,153
Gathering Systems | Crude Oil Sales — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party										281,205	189,772	141,490
Fresh Water Delivery
Segment Reporting Information
Midstream Services — Affiliate										57,834	77,566	69,266
Total Revenues										65,514	90,157	88,611
Cost of Crude Oil Sales										0	0
Direct Operating Expense										8,663	18,650	14,269
Depreciation and Amortization										2,913	2,526	2,259
Goodwill Impairment										0
Income (Loss) Before Income Taxes										53,939	68,980	72,083
Intangible Assets, Net		0				0				0	0
Goodwill		0				0				0	0
Total Assets		105,599				91,840				105,599	91,840
Additions to Long-Lived Assets										0	7,330
Fresh Water Delivery | Midstream Services — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party										7,680	12,591	19,345
Fresh Water Delivery | Crude Oil Sales — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party										0	0	0
Investments in Midstream Entities
Segment Reporting Information
Midstream Services — Affiliate										0	0	0
Total Revenues										0	0	0
Cost of Crude Oil Sales										0	0
Direct Operating Expense										0	0	0
Depreciation and Amortization										0	0	0
Goodwill Impairment										0
Income (Loss) Before Income Taxes										(34,891)	(17,748)	16,289
Intangible Assets, Net		0				0				0	0
Goodwill		0				0				0	0
Total Assets		904,955				660,778				904,955	660,778
Additions to Long-Lived Assets										317,229	611,325
Investments in Midstream Entities | Midstream Services — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party										0	0	0
Investments in Midstream Entities | Crude Oil Sales — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party										0	0
Corporate
Segment Reporting Information
Midstream Services — Affiliate										0	0	0
Total Revenues										0	0	0
Cost of Crude Oil Sales										0	0
Direct Operating Expense										3,510	2,282	1,735
Depreciation and Amortization										0	0	0
Goodwill Impairment										0
Income (Loss) Before Income Taxes										(54,802)	(44,295)	(36,478)
Intangible Assets, Net		0				0				0	0
Goodwill		0				0				0	0
Total Assets		$ 11,707				$ 13,438				11,707	13,438
Additions to Long-Lived Assets										523	1,068
Corporate | Midstream Services — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party										0	0	0
Corporate | Crude Oil Sales — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party										$ 0	$ 0

Unit-Based Compensation - Narra

Unit-Based Compensation - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award
Unit-based compensation expense	$ 2.2	$ 1.1	$ 1.4
Noble Midstream Partners LP 2016 Long-Term incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award
Authorized (in units)	1,860,000
Units available for grant (in units)	1,484,907
Noble Midstream Partners LP 2016 Long-Term incentive Plan | Restricted Units
Share-based Compensation Arrangement by Share-based Payment Award
Unrecognized unit based compensation expense	$ 2.4
Period for recognition	1 year 3 months 18 days

Unit-Based Compensation - Unit

Unit-Based Compensation - Unit Award Activity (Details) - Noble Midstream Partners LP 2016 Long-Term incentive Plan - Restricted Units	12 Months Ended
	Dec. 31, 2020$ / sharesshares
Number of Units
Awarded and Unvested Units, beginning balance (in units) | shares	103,355
Awarded (in units) | shares	145,731
Vested (in units) | shares	(48,809)
Forfeited (in units) | shares	(27,194)
Awarded and Unvested Units, ending balance (in units) | shares	173,083
Weighted Average Award Date Fair Value
Awarded and Unvested Units, beginning balance (in dollars per share) | $ / shares	$ 36.04
Awarded (in dollars per share) | $ / shares	22.40
Vested (in dollars per share) | $ / shares	36.41
Forfeited (in dollars per share) | $ / shares	25.92
Awarded and Unvested Units, ending balance (in dollars per share) | $ / shares	$ 26.04

Partnership Distributions - Nar

Partnership Distributions - Narrative (Details) - $ / shares

Jan. 22, 2021

May 14, 2019

Apr. 25, 2019

Sep. 30, 2020

Jun. 30, 2020

Mar. 31, 2020

Dec. 31, 2019

Sep. 30, 2019

Jun. 30, 2019

Mar. 31, 2019

Dec. 31, 2018

Sep. 30, 2018

Jun. 30, 2018

Mar. 31, 2018

Dec. 31, 2017

Dec. 31, 2020

Distribution Made to Limited Partner

Partner distribution period

45 days

Distribution per limited partner unit (in dollars per share)

$ 0.6132

$ 0.1875

$ 0.1875

$ 0.1875

$ 0.6878

$ 0.6716

$ 0.6418

$ 0.6132

$ 0.5858

$ 0.5597

$ 0.5348

$ 0.5110

$ 0.4883

Common Units | Subsequent Event

Distribution Made to Limited Partner

Distribution per limited partner unit (in dollars per share)

$ 0.1875

Limited Partner | Subordinated Units

Distribution Made to Limited Partner

Partners' capital account, units, converted (units)

15,902,584

Partnership Distributions - Dis

Partnership Distributions - Distributions (Details) - USD ($) $ / shares in Units, $ in Thousands	Apr. 25, 2019	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Distribution Made to Limited Partner
Distribution per Limited Partner Unit (in dollars per share)	$ 0.6132	$ 0.1875	$ 0.1875	$ 0.1875	$ 0.6878	$ 0.6716	$ 0.6418	$ 0.6132	$ 0.5858	$ 0.5597	$ 0.5348	$ 0.5110	$ 0.4883
Distribution to Limited Partners		$ 16,907	$ 16,907	$ 16,906	$ 62,012	$ 32,418	$ 30,058	$ 27,792	$ 25,613	$ 23,621	$ 22,306	$ 21,048	$ 19,851
Holder of IDRs		0	0	0	0	5,820	4,640	3,507	2,421	1,462	1,134	819	520
Common Units
Distribution Made to Limited Partner
Distribution to Limited Partners		16,907	16,907	16,906	62,012	26,598	25,418	14,534	13,876	13,258	12,668	12,103	11,566
Subordinated Units
Distribution Made to Limited Partner
Distribution to Limited Partners		$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 9,751	$ 9,316	$ 8,901	$ 8,504	$ 8,126	$ 7,765

Net Income Per Limited Partne_3

Net Income Per Limited Partner Unit - Calculation of Net Income per Limited Partner Units (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share, Diluted, by Common Class, Including Two Class Method
Net Income Attributable to Noble Midstream Partners LP									$ 134,031	$ 159,996	$ 162,734
Less: Net Income Attributable to Incentive Distribution Rights									0	13,967	5,836
Net Income Attributable to Limited Partners	$ 39,908	$ 35,784	$ 48,236	$ 10,103	$ 39,396	$ 34,812	$ 31,769	$ 40,052	$ 134,031	$ 146,029	$ 156,898
Antidilutive Restricted Units (in shares)									184	54	24
Common Units
Earnings Per Share, Diluted, by Common Class, Including Two Class Method
Net Income Attributable to Limited Partners									$ 134,031	$ 123,662	$ 93,875
Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic (in dollars per share)	$ 0.44	$ 0.40	$ 0.53	$ 0.11	$ 0.65	$ 0.88	$ 0.79	$ 1.01	$ 1.49	$ 3.09	$ 3.96
Net Income Attributable to Limited Partners Per Limited Partner Unit — Diluted (in dollars per share)									$ 1.49	$ 3.08	$ 3.96
Weighted Average Limited Partner Units Outstanding — Basic (in shares)									90,165	40,083	23,686
Weighted Average Limited Partner Units Outstanding — Diluted (in shares)									90,167	40,105	23,701
Subordinated Units
Earnings Per Share, Diluted, by Common Class, Including Two Class Method
Net Income Attributable to Limited Partners									$ 0	$ 22,367	$ 63,023
Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic (in dollars per share)					$ 0	$ 0	$ 0.84	$ 1.01	$ 0	$ 3.86	$ 3.96
Net Income Attributable to Limited Partners Per Limited Partner Unit — Diluted (in dollars per share)									$ 0	$ 3.86	$ 3.96
Weighted Average Limited Partner Units Outstanding — Basic (in shares)									0	5,795	15,903
Weighted Average Limited Partner Units Outstanding — Diluted (in shares)									0	5,795	15,903

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details)	12 Months Ended
	Dec. 31, 2020USD ($)
Minimum
Loss Contingencies
Amount sought	$ 300,000

Commitments and Contingencies_2

Commitments and Contingencies - Summary of Future Obligations (Details) $ in Thousands	Dec. 31, 2020USD ($)
Future Minimum Finance Lease Payments
2021	$ 2,063
2022	0
2023	0
2024	0
2025	0
2026 and Beyond	0
Total	2,063
Purchase Obligations
2021	2,064
2022	0
2023	0
2024	0
2025	0
2026 and Beyond	0
Total	2,064
Lease Obligations
2021	38,705
2022	34,371
2023	35,055
2024	36,130
2025	36,752
2026 and Beyond	29,770
Total	210,783
Future Minimum Operating Lease Payments
Lease Obligations
2021	260
2022	0
2023	0
2024	0
2025	0
2026 and Beyond	0
Total	260
Surface Lease Obligations
Lease Obligations
2021	217
2022	176
2023	176
2024	176
2025	176
2026 and Beyond	3,698
Total	4,619
Transportation Fees
Contractual Obligations
2021	34,101
2022	34,195
2023	34,879
2024	35,954
2025	36,576
2026 and Beyond	26,072
Total	$ 201,777

Income Taxes - Components of In

Income Taxes - Components of Income Tax Provision (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Current	$ (161)	$ 541	$ 1,323
Deferred	544	3,474	6,678
Tax Provision	$ 383	$ 4,015	$ 8,001
Effective Tax Rate	0.40%	1.60%	3.60%

Supplemental Quarterly Financ_3

Supplemental Quarterly Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Quarterly
Total Revenues	$ 207,265	$ 187,365	$ 145,950	$ 224,045	$ 190,765	$ 181,674	$ 170,660	$ 160,702	$ 764,625	$ 703,801	$ 558,735
Operating Income	58,309	62,071	61,431	(25,101)	69,644	81,271	60,564	71,987	156,710	283,466	218,878
Income Before Income Taxes	42,982	38,902	50,732	(37,367)	52,190	71,698	56,494	69,100	95,249	249,482	224,720
Net Income	42,786	38,736	50,860	(37,516)	51,394	70,519	55,763	67,791	94,866	245,467	216,719
Net Income Attributable to Limited Partners	$ 39,908	$ 35,784	$ 48,236	$ 10,103	$ 39,396	$ 34,812	$ 31,769	$ 40,052	134,031	146,029	156,898
Common Units
Quarterly
Net Income Attributable to Limited Partners									$ 134,031	$ 123,662	$ 93,875
Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic (in dollars per share)	$ 0.44	$ 0.40	$ 0.53	$ 0.11	$ 0.65	$ 0.88	$ 0.79	$ 1.01	$ 1.49	$ 3.09	$ 3.96
Subordinated Units
Quarterly
Net Income Attributable to Limited Partners									$ 0	$ 22,367	$ 63,023
Net Income Attributable to Limited Partners Per Limited Partner Unit — Basic (in dollars per share)					$ 0	$ 0	$ 0.84	$ 1.01	$ 0	$ 3.86	$ 3.96