Summary of Significant Accounting Policies and Basis of Presentation (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Presentation	Basis of Presentation and Consolidation The accompanying consolidated financial statements for periods prior to September 20, 2016 represent the Contributed Businesses as the accounting Predecessor to the Partnership, presented on a carve-out basis of Noble’s historical ownership of the Predecessor. The Predecessor financial statements have been prepared from the separate records maintained by Noble and may not necessarily be indicative of the actual results of operations that might have occurred if the Predecessor had been operated separately during the periods reported. Because a direct ownership relationship did not exist among the businesses comprising the Predecessor, the net investment in the Predecessor is shown as Parent Net Investment, in lieu of partners’ equity, in the accompanying Consolidated Statement of Changes in Equity for years prior to December 31, 2016. 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 our accounts and the accounts of the DevCos, each of which we control as General Partner. We have determined that the partners with equity at risk in each of the DevCos lack the authority, through voting rights or similar rights, to direct the activities that most significantly impact their economic performance. Therefore, each DevCo is considered a variable interest entity (VIE). Through our 100% ownership interest in Noble Midstream Services, LLC, a Delaware limited liability company which owns controlling interests in each of the DevCos, 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 each of the DevCos in our financial statements. A substantial portion of the financial statement activity associated with our DevCos is captured within the Gathering Systems and Fresh Water Delivery reportable segments. Although our investment in the Advantage Joint Venture is owned by Trinity River DevCo LLC, all financial statement activity associated with our investment is captured within the Investments and Other reportable segment. See Note 8. Segment Information. 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 company board of directors as well as our responsibility as operator of the acquired 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.
Equity Method of Accounting	Equity Method of Accounting Although we serve as the operator of the Advantage system, our operating agreements empower the Advantage board, split between us and Plains, to direct the activities that most significantly affect the long-term economic performance of the entity, primarily the oversight of the commercial function and approval of expansion capital. As a result, our investment in the Advantage Joint Venture does not require consolidation under the VIE consolidation model. We use the equity method of accounting for our investment in the Advantage Joint Venture, as we do not control, but do exert significant influence over, its operations. 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 of 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.
Noncontrolling Interests	Noncontrolling Interests We present our consolidated financial statements with a noncontrolling interest section representing Noble’s retained ownership our DevCos as well as Greenfield Member's ownership of Black Diamond.
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.
Revenue Recognition	Revenue Recognition We generate revenues primarily 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. We recognize revenue when services have been rendered, the prices are fixed or determinable, and collectibility is reasonable assured.
Property, Plant and Equipment	Property, Plant and Equipment Property and equipment primarily consists of crude oil and natural gas gathering systems, 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 $2.5 million in 2017, $0.8 million in 2016, and $2.5 million in 2015. Repair and maintenance costs are expensed as incurred. 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 30 years. The depreciation of fixed assets recorded under capital lease agreements is included in depreciation and amortization expense.
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, and increases in 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.
Asset Retirement Obligations	Asset Retirement Obligations Asset Retirement Obligations (ARO) 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.
Impairment of Investments	Impairment of 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.
Fair Value Measurements	Fair Value Measurements 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.
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.
Transactions With Affiliates	Transactions with Affiliates Transactions between Noble, its affiliates and us have been identified in the consolidated financial statements as transactions with affiliates.
Debt Origination Fees and Expenses	Debt Origination Fees and Expenses Debt origination fees and expenses of $1.9 million associated with our Revolving Credit Facility are included in deferred charges and amortized on a straight line basis over the five-year term. Amortization is included in interest expense.
Capital Lease Obligation	Capital Lease Obligation We entered into a capital lease for a pond to be used in our fresh water delivery system. The amount of the capital lease obligation is based on the discounted present value of future minimum lease payments, and therefore does not reflect future cash lease payments.
Unit-Based Compensation	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.
Income Taxes	Income Taxes We are not a taxable entity for U.S. 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 accordingly for the periods subsequent to the IPO, we do not record deferred taxes related to the aggregate difference in the basis of our assets for financial and tax reporting purposes. During 2017, we commenced operations in the Delaware Basin and are subject to a Texas Margin Tax. For periods prior to the IPO, our consolidated financial statements include a provision for tax expense on income related to the assets that Noble contributed to the Partnership at the IPO date. 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.
Litigation and Other Contingencies	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.
Concentration of Credit Risk	Concentration of Credit Risk For the year ended December 31, 2017, 94% of our revenues are from Noble and its affiliates. For all other periods presented, 100% of our revenues are from Noble and its affiliates.
Recently Issued Accounting Standards	Recently Issued Accounting Standards Compensation – Stock Compensation (Topic 718): Scope of Modification Accounting In May 2017, the FASB issued Accounting Standards Update No. 2017-09 (ASU 2017-09) Compensation - Stock Compensation (Topic 718). The purpose of this update is to provide clarity as to which modifications of awards require modification accounting under Topic 718, whereas previously issued guidance frequently resulted in varying interpretations and a diversity of practice. Under ASU 2017-09, an entity should employ modification accounting unless the following items are met: (1) the fair value of the award is the same immediately before and after the award is modified; (2) the vesting conditions are the same under both the modified award and the original award; and (3) the classification of the modified award is the same as the original award, either equity or liability. Regardless of whether modification accounting is utilized, award disclosure requirements under Topic 718 remain unchanged. ASU 2017-09 will be effective for annual or any interim periods beginning after December 15, 2017. We do not believe adoption of ASU 2017-09 will have a material impact on our financial statements. We will adopt the new standard on the effective date of January 1, 2018. Business Combinations – Clarifying the Definition of a Business In January 2017, the FASB issued Account Standards Update No. 2017-01 (ASU 2017-01): Business Combinations - Clarifying the Definition of a Business, that assists in determining whether certain transactions should be accounted for as acquisitions or dispositions of assets or businesses. The amendment provides a screen to be applied to the fair value of an acquisition or disposal to evaluate whether the assets in question are simply assets or if they meet the definition of a business. If the screen is not met, no further evaluation is needed. If the screen is met, certain steps are subsequently taken to make the determination. This ASU is effective for annual and interim periods beginning after December 15, 2017 and is required to be applied prospectively. We will adopt the new standard on the effective date of January 1, 2018. Statement of Cash Flows – Restricted Cash In November 2016, the FASB issued Accounting Standards Update No. 2016-18 (ASU 2016-18): Statement of Cash Flows - Restricted Cash, which requires amounts generally described as restricted cash and restricted cash equivalents be included with cash and cash equivalents when reconciling the total beginning and ending amounts for the periods shown on the statement of cash flows. This ASU will be effective for annual and interim periods beginning after December 15, 2017, with earlier application permitted. We will adopt the new standard on the effective date of January 1, 2018. Under the provisions of ASU 2016-18, we will no longer reflect a cash outflow for cash becoming restricted. Additionally, the statement of cash flows will reconcile changes in both cash and restricted cash. Based on the balance of restricted cash as of December 31, 2017, adoption of ASU 2016-18 will have a material impact on our consolidated statement of cash flows and related disclosures. Statement of Cash Flows – Classification of Certain Cash Receipts and Cash Payments In August 2016, the FASB issued Accounting Standards Update No. 2016-15 (ASU 2016-15): Statement of Cash Flows - Classification of Certain Cash Receipts and Cash Payments, to clarify how eight specific cash receipt and cash payment transactions should be presented in the statement of cash flows. ASU 2016-15 will be effective for annual and interim periods beginning after December 15, 2017, with earlier application permitted. We will adopt the new standard on the effective date of January 1, 2018. Leases In February 2016, the FASB issued Accounting Standards Update No. 2016-02 (ASU 2016-02): Leases. The guidance requires lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by leases with terms of more than 12 months. ASU 2016-02 also requires disclosures designed to give financial statement users information on the amount, timing, and uncertainty of cash flows arising from leases. The standard will be effective for annual and interim periods beginning after December 15, 2018, with earlier application permitted. In the normal course of business, we enter into capital and operating lease agreements to support our operations and may lease water-related, field-related and other assets. At this time, we cannot reasonably estimate the financial impact ASU 2016-02 will have on our financial statements; however, we believe adoption and implementation of ASU 2016-02 will likely materially impact our balance sheet resulting from an increase in both assets and liabilities relating to our leasing activities. As part of our assessment to date, we have formed an implementation work team, prepared educational and training materials pertinent to ASU 2016-02 and have begun contract review and documentation. Revenue Recognition In May 2014, the FASB issued Accounting Standards Update No. 2014-09 (ASU 2014-09), which creates Topic 606, Revenue from Contracts with Customers. In summary, revenue recognition would occur upon the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. Additionally, ASU 2014-09 requires enhanced financial statement disclosures over revenue recognition. We continue to evaluate the impact of ASU 2014-09 on our accounting policies, internal controls, and consolidated financial statements and related disclosures. We have performed a review of contracts for each of our revenue streams and are developing accounting policies to address the provisions of ASU 2014-09. We have evaluated the impact on the presentation of our future revenues and expenses under the gross-versus-net presentation guidance. Based upon assessments performed to date, we do not expect ASU 2014-09 to have an effect on the timing of revenue recognition or our financial position. We will adopt the new standard on the effective date of January 1, 2018. After adoption of ASU 2015-09, we will begin to net certain immaterial revenues and expenses using the modified retrospective approach in accordance with the gross-versus-net presentation guidance.