Summit Midstream Partners (SMLP) 10-K 1 Mar 23 2022 FY Annual report Financial data

COVER PAGE

COVER PAGE - USD ($)	12 Months Ended
	Dec. 31, 2022	Feb. 24, 2023	Jun. 30, 2022
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2022
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-35666
Entity Registrant Name	Summit Midstream Partners, LP
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	45-5200503
Entity Address, Address Line One	910 Louisiana Street
Entity Address, Address Line Two	Suite 4200
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77002
City Area Code	832
Local Phone Number	413-4770
Title of 12(b) Security	Common Units
Trading Symbol	SMLP
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 129,415,408
Entity Common Stock, Shares Outstanding		10,182,763
Documents Incorporated by Reference	Portions of the registrant’s definitive proxy statement relating to its 2023 Annual Meeting of Limited Partners, which will be filed with the Securities and Exchange Commission within 120 days of December 31, 2022, are incorporated by reference into Part III of this Annual Report on Form 10-K where indicated.
Entity Central Index Key	0001549922
Amendment Flag	false
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY

AUDIT INFORMATION

AUDIT INFORMATION	12 Months Ended
	Dec. 31, 2022
Audit Information [Abstract]
Auditor Name	Deloitte & Touche LLP
Auditor Location	Houston, Texas
Auditor Firm ID	34

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
ASSETS
Cash and cash equivalents	$ 11,808	$ 7,349
Restricted cash	1,723	12,223
Accounts receivable	75,287	62,121
Other current assets	8,724	5,676
Total current assets	97,542	87,369
Property, plant and equipment, net	1,718,754	1,726,082
Total intangibles, net	198,718	172,927
Investment in equity method investees	506,677	523,196
Other noncurrent assets	38,273	12,888
TOTAL ASSETS	2,559,964	2,522,462
LIABILITIES AND CAPITAL
Trade accounts payable	14,052	10,498
Accrued expenses	20,601	14,462
Deferred revenue	9,054	10,374
Ad valorem taxes payable	10,245	8,570
Accrued compensation and employee benefits	16,319	11,019
Accrued interest	17,355	12,737
Accrued environmental remediation	1,365	3,068
Accrued settlement payable	6,667	4,833
Current portion of long-term debt	10,507	0
Other current liabilities	11,724	3,676
Total current liabilities	117,889	79,237
Long-term debt, net	1,479,855	1,355,072
Noncurrent deferred revenue	37,694	42,570
Noncurrent accrued environmental remediation	2,340	2,538
Other noncurrent liabilities	38,784	32,357
Total liabilities	1,676,562	1,511,774
Commitments and contingencies (Note 10)
Mezzanine Capital
Subsidiary Series A Preferred Units (93,039 and 91,439 units issued and outstanding at December 31, 2022 and December 31, 2021, respectively)	118,584	106,325
Partners Capital
Series A Preferred Units (65,508 and 143,447 units issued and outstanding at December 31, 2022 and December 31, 2021, respectively)	85,327	169,769
Common limited partner capital (10,182,763 and 7,169,834 units issued and outstanding at December 31, 2022 and December 31, 2021, respectively)	679,491	734,594
Total partners capital	764,818	904,363
TOTAL LIABILITIES AND CAPITAL	$ 2,559,964	$ 2,522,462

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - shares	Dec. 31, 2022	Dec. 31, 2021
Partners Capital
Common limited partner capital, issued (in shares)	10,182,763	7,169,834
Common limited partner capital, outstanding (in shares)	10,182,763	7,169,834
Subsidiary Series A Preferred Units
Subsidiary Series A preferred unitholders, issued (in shares)	93,039,000	91,439,000
Subsidiary Series A preferred unitholders, outstanding (in shares)	93,039,000	91,439,000
Series A Preferred Units
Subsidiary Series A preferred unitholders, issued (in shares)	65,508	143,447
Subsidiary Series A preferred unitholders, outstanding (in shares)	65,508	143,447

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Revenues:
Total revenues	$ 369,594	$ 400,618
Costs and expenses:
Type of Cost, Good or Service [Extensible List]	Natural Gas Liquids [Member]	Natural Gas Liquids [Member]
Cost of natural gas and NGLs	$ 76,826	$ 81,969
Operation and maintenance	84,152	74,178
General and administrative	44,943	58,166
Depreciation and amortization	119,055	119,076
Transaction costs	6,968	1,677
Gain on asset sales, net	(507)	(369)
Long-lived asset impairment	91,644	10,151
Total costs and expenses	423,081	344,848
Other expense, net	(4)	(613)
Gain on interest rate swaps	16,414	0
Loss on sale of business	(1,741)	0
Loss on ECP Warrants	0	(13,634)
Interest expense	(102,459)	(66,156)
Loss on early extinguishment of debt	0	(3,523)
Loss before income taxes and equity method investment income	(141,277)	(28,156)
Income tax (expense) benefit	(325)	327
Income from equity method investees	18,141	7,880
Net loss	(123,461)	(19,949)
Add: deemed capital contribution	20,974	8,326
Net loss attributable to Summit Midstream Partners, LP	(140,605)	(36,616)
Series A Preferred Units
Costs and expenses:
Net income (loss) attributable to limited partners	(8,048)	(15,998)
Common units
Costs and expenses:
Net income (loss) attributable to limited partners	$ (127,679)	$ (44,288)
Net loss per limited partner unit:
Common unit - basic (in dollars per share)	$ (12.71)	$ (6.57)
Common unit - diluted (in dollars per share)	$ (12.71)	$ (6.57)
Weighted-average limited partner units outstanding:
Common units - basic (in shares)	10,048	6,741
Common units - diluted (shares)	10,048	6,741
Subsidiary | Series A Preferred Units
Costs and expenses:
Net income (loss) attributable to limited partners	$ (17,144)	$ (16,667)
Gathering services and related fees
Revenues:
Total revenues	248,358	281,705
Natural gas, NGLs and condensate sales
Revenues:
Total revenues	86,225	82,768
Other revenues
Revenues:
Total revenues	$ 35,011	$ 36,145

CONSOLIDATED STATEMENTS OF PART

CONSOLIDATED STATEMENTS OF PARTNERS' CAPITAL - USD ($) $ in Thousands	Total	Partners' Capital	Partners' Capital Series A Preferred Units
Beginning balance at Dec. 31, 2020	$ 922,891	$ 748,466	$ 174,425
Net income (loss)	(36,616)	(52,614)	15,998
Unit-based compensation	4,744	4,744
Tax withholdings and associated payments on vested SMLP LTIP awards	(1,733)	(1,733)
Tax withholdings on Series A Preferred Unit Exchange and 2022 Preferred Exchange Offer	(465)	(465)
Effect of 2021 Preferred Exchange Offer, inclusive of deemed contribution to common unit holders	0	20,654	(20,654)
Exercise of ECP Warrants	15,542	15,542
Ending balance at Dec. 31, 2021	904,363	734,594	169,769
Net income (loss)	(140,598)	(148,743)	8,145
Unit-based compensation	3,778	3,778
Tax withholdings and associated payments on vested SMLP LTIP awards	(1,198)	(1,198)
Tax withholdings on Series A Preferred Unit Exchange and 2022 Preferred Exchange Offer	(2,652)	(2,652)
LTIP cash to equity conversion	1,125	1,125
Effect of 2021 Preferred Exchange Offer, inclusive of deemed contribution to common unit holders	0	92,587	(92,587)
Exercise of ECP Warrants	0
Ending balance at Dec. 31, 2022	$ 764,818	$ 679,491	$ 85,327

CONSOLIDATED STATEMENTS OF PA_2

CONSOLIDATED STATEMENTS OF PARTNERS' CAPITAL (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Statement of Partners' Capital [Abstract]
Deemed contribution to common unit holders	$ 20.9	$ 8.3

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net loss	$ (123,461)	$ (19,949)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	119,993	119,995
Noncash lease expense	885	1,104
Amortization of debt issuance costs	9,326	7,017
Unit-based and noncash compensation	3,778	4,744
Income from equity method investees	(18,141)	(7,880)
Distributions from equity method investees	43,040	26,760
Gain on asset sales, net	(507)	(369)
Loss on sale of business	1,741	0
Loss on extinguishment of debt	0	3,245
Loss on ECP Warrants and other	0	13,635
Unrealized (gain) loss on interest rate swaps	(16,016)	779
Long-lived asset impairment	91,644	10,151
Changes in operating assets and liabilities:
Accounts receivable	284	(178)
Trade accounts payable	2,248	(89)
Accrued expenses	(2,780)	1,422
Deferred revenue, net	(6,082)	(5,295)
Ad valorem taxes payable	14	(516)
Accrued interest	4,618	4,730
Accrued environmental remediation, net	(1,901)	2,676
Other, net	(9,939)	3,117
Net cash provided by operating activities	98,744	165,099
Cash flows from investing activities:
Capital expenditures	(30,472)	(25,030)
Proceeds from asset sale	4,945	8,000
Investment in Double E equity method investee	(8,444)	(148,699)
Net cash used in investing activities	(226,558)	(165,729)
Cash flows from financing activities:
Borrowings from 2026 Secured Notes	84,371	689,500
Repayment of 2022 Senior Notes	0	(234,047)
Borrowings from Permian Transmission Credit Facility	0	160,000
Repayments on Permian Transmission Term Loan	(4,647)	0
Borrowings from ABL Facility	293,000	300,000
Repayments of ABL Facility	(230,000)	(33,000)
Repayments of Revolving Credit Facility	0	(857,000)
Debt issuance costs	(14,409)	(20,228)
Distributions on Subsidiary Series A Preferred Units	(3,257)	0
Proceeds from asset sale	0	357
Other, net	(3,285)	(924)
Net cash provided by financing activities	121,773	4,658
Net change in cash, cash equivalents and restricted cash	(6,041)	4,028
Cash, cash equivalents and restricted cash, beginning of period	19,572	15,544
Cash, cash equivalents and restricted cash, end of period	13,531	19,572
Lane G&P System
Cash flows from investing activities:
Proceeds from sale of business, net of cash sold in transaction	75,020	0
Bison Midstream, LLC
Cash flows from investing activities:
Proceeds from sale of business, net of cash sold in transaction	38,920	0
Outrigger DJ
Cash flows from investing activities:
Cash consideration paid for the acquisition, net of cash acquired	(166,631)	0
Sterling DJ
Cash flows from investing activities:
Cash consideration paid for the acquisition, net of cash acquired	$ (139,896)	$ 0

ORGANIZATION, BUSINESS OPERATIO

ORGANIZATION, BUSINESS OPERATIONS AND PRESENTATION AND CONSOLIDATION	12 Months Ended
	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
ORGANIZATION, BUSINESS OPERATIONS AND PRESENTATION AND CONSOLIDATION	1. ORGANIZATION, BUSINESS OPERATIONS AND PRESENTATION AND CONSOLIDATION Organization. Summit Midstream Partners, LP (including its subsidiaries, collectively “SMLP” or the “Partnership”) is a Delaware limited partnership that was formed in May 2012 and began operations in October 2012. SMLP is a value-oriented limited partnership focused on developing, owning and operating midstream energy infrastructure assets that are strategically located in unconventional resource basins, primarily shale formations, in the continental United States. The Partnership’s business activities are primarily conducted through various operating subsidiaries, each of which is owned or controlled by its wholly owned subsidiary holding company, Summit Holdings, a Delaware limited liability company. As of December 31, 2022, the Partnership indirectly owns its General Partner, and the General Partner is a wholly owned, indirect subsidiary of the Partnership. The General Partner has no assets or liabilities and holds the non-economic general partner interest in the Partnership. Business Operations. The Partnership provides natural gas gathering, compression, treating and processing services as well as crude oil and produced water gathering services pursuant to primarily long-term, fee-based agreements with its customers. In addition to these services, the Partnership also provides freshwater delivery services pursuant to short-term agreements with customers. The Partnership’s results are primarily driven by the volumes of natural gas that it gathers, compresses, treats and/or processes as well as by the volumes of crude oil and produced water that it gathers. Other than the Partnership’s investments in Double E and Ohio Gathering, all of its business activities are conducted through wholly owned operating subsidiaries. Presentation and Consolidation. The Partnership prepares its consolidated financial statements in accordance with GAAP as established by the FASB. The Partnership makes estimates and assumptions that affect the reported amounts of assets and liabilities at the balance sheet dates, including fair value measurements, the reported amounts of revenues and expenses and the disclosure of commitments and contingencies. Although management believes these estimates are reasonable, actual results could differ from its estimates. The consolidated financial statements include the assets, liabilities and results of operations of SMLP and its subsidiaries. All intercompany transactions among the consolidated entities have been eliminated in consolidation. Comprehensive income or loss is the same as net income or loss for all periods presented.

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND RECENTLY ISSUED ACCOUNTING STANDARDS APPLICABLE TO THE PARTNERSHIP Cash, Cash Equivalents and Restricted Cash. The Partnership considers all highly liquid investments with an original maturity of three months or less to be cash equivalents. Cash that is held by a major bank and has restrictions on its availability to the Partnership is classified as restricted cash. The restricted cash balance of $1.7 million and $12.2 million at December 31, 2022 and 2021, respectively, is related to proceeds which are available to finance Permian Transmission’s debt service or other general corporate purposes of Permian Transmission. See Note 9 - Debt for additional information. Accounts Receivable. Accounts receivable relate to gathering and other services provided to the Partnership’s customers and other counterparties. The Partnership evaluates the collectability of accounts receivable and the need for an allowance for doubtful accounts based on customer-specific facts and circumstances. To the extent the collectability of a specific customer or counterparty receivable is doubtful, the Partnership recognizes an allowance for doubtful accounts. Uncollectible receivables are written off when a settlement is reached for an amount that is less than the outstanding historical balance or a receivable amount is deemed otherwise unrealizable. Property, Plant and Equipment. The Partnership records property, plant and equipment at historical cost of construction or fair value of the assets at acquisition. The Partnership capitalizes expenditures that extend the useful life of an asset or enhance its productivity or efficiency from its original design over the expected remaining period of use. For maintenance and repairs that do not add capacity or extend the useful life of an asset, the Partnership recognizes expenditures as an expense as incurred. The Partnership capitalizes project costs incurred during construction, including interest on funds borrowed to finance the construction of facilities and pipelines, as construction in progress. Accrued capital expenditures are reflected in trade accounts payable. The Partnership records depreciation on a straight-line basis over an asset’s estimated useful life and bases its estimates for useful life on various factors including age (in the case of acquired assets), manufacturing specifications, technological advances and historical data concerning useful lives of similar assets. Estimates of useful lives follow. Useful lives Gathering and processing systems and related equipment 12-30 Other 4-15 Construction in progress is depreciated consistent with its applicable asset class once it is placed in service. Land and line fill are not depreciated. The Partnership bases an asset’s carrying value on estimates, assumptions and judgments for useful life and salvage value. Upon sale, retirement or other disposal, the Partnership removes the carrying value of an asset and its accumulated depreciation from its balance sheet and recognizes the related gain or loss, if any. Asset Retirement Obligations. The Partnership records a liability for asset retirement obligations only if and when a future asset retirement obligation with a determinable life is identified. For identified asset retirement obligations, the Partnership evaluates whether the expected retirement date and related costs of retirement can be estimated. The Partnership has concluded that its gathering and processing assets have an indeterminate life because they are owned and will operate for an indeterminate period when properly maintained. Because the Partnership does not have sufficient information to reasonably estimate the amount or timing of such obligations and does not have any current plan to discontinue use of any significant assets, the Partnership did not provide for any asset retirement obligations as of December 31, 2022 or 2021. Amortizing Intangibles. The Partnership has certain acquired gas gathering contracts that had above-market pricing structures at the acquisition date and the Partnership amortizes these favorable contracts using a straight-line method over the contract’s estimated useful life. The Partnership defines useful life as the period over which the contract is expected to contribute to the Partnership’s future cash flows. These favorable contracts have original terms ranging from 10 years to 20 years and the Partnership recognizes the amortization expense associated with these contracts in Other revenues. The Partnership amortizes all other gas gathering contracts, or contract intangibles, over the period of economic benefit based upon expected revenues over the life of the contract. The useful life of these contracts ranges from 3 years to 25 years. The Partnership recognizes the amortization expense associated with these contracts in Depreciation and amortization expense. The Partnership also has rights-of-way associated with municipal easements and easements granted within existing rights-of-way. The Partnership amortizes these intangible assets over the shorter of the contractual term of the rights-of-way or the estimated useful life of the gathering system. The contractual terms of the rights-of-way range from 20 years to 30 years and the Partnership recognizes the amortization expense associated with these rights-of-way assets in Depreciation and amortization expense. Equity Method Investments. The Partnership accounts for investments in which it exercises significant influence using the equity method so long as it (i) does not control the investee and (ii) is not the primary beneficiary. The Partnership reflects these investments in its consolidated balance sheets under the caption titled “investment in equity method investees.” The Partnership recognizes an other-than-temporary impairment for losses in the value of equity method investees when evidence indicates that the carrying amount is no longer supportable. Evidence of a loss in value might include, but is not limited to, absence of an ability to recover the carrying amount of the investment or an inability of the equity method investee to sustain an earnings capacity that would justify the carrying amount of the investment. A current fair value of an investment that is less than its carrying amount may indicate a loss in value of the investment. The Partnership evaluates its equity method investments for impairment whenever a triggering event exists that would indicate a need to assess the investment for potential impairment. Impairment of Long-Lived Assets. The Partnership tests assets for impairment when events or circumstances indicate the carrying value of a long-lived asset may not be recoverable. The carrying value of a long-lived asset is not recoverable if it exceeds the sum of the undiscounted cash flows expected to result from its use and eventual disposition. If the Partnership concludes that an asset’s carrying value will not be recovered through future cash flows, the Partnership recognizes an impairment loss on the long-lived asset equal to the amount by which the carrying value exceeds its fair value. The Partnership determines fair value using a combination of market-based and income-based approaches. Environmental Matters. The Partnership is subject to various federal, state and local laws and regulations relating to the protection of the environment. Liabilities for loss contingencies, including environmental remediation costs, arising from claims, assessments, litigation, fines and penalties and other sources are charged to expense when it is probable that a liability has been incurred and the amount of the assessment and/or remediation can be reasonably estimated. The Partnership accrues for losses associated with environmental remediation obligations when such losses are probable and reasonably estimable. Such accruals are adjusted as further information develops or circumstances change. Recoveries of environmental remediation costs from other parties or insurers are recorded as assets when their realization is assured beyond a reasonable doubt. Commitments and Contingencies. When required, the Partnership records accruals for loss contingencies in accordance with FASB ASC 450, Contingencies . Such determinations are subject to interpretations of current facts and circumstances, forecasts of future events and estimates of the financial impacts of such events. Mezzanine Capital . A noncontrolling interest is reported as a component of equity unless the noncontrolling interest is considered redeemable, in which case the noncontrolling interest is recorded between liabilities and equity (mezzanine or temporary equity) in the Partnership’s consolidated balance sheet. Revenue. The Partnership provides gathering and/or processing services principally under contracts that contain one or more of the following arrangements described below: • Fee-based arrangements. Under fee-based arrangements, the Partnership receives a fee or fees for one or more of the following services (i) natural gas gathering, treating, transporting, compressing and/or processing and (ii) crude oil and/or produced water gathering and (iii) fresh water delivery services. • Percent-of-proceeds arrangements. Under percent-of-proceeds arrangements, the Partnership generally purchases natural gas from producers at the wellhead, or other receipt points, gathers the wellhead natural gas through its gathering system, treats and compresses the natural gas, processes the natural gas and/or sells the natural gas to a third party for processing. The Partnership then remits to its producers an agreed-upon percentage of the actual proceeds received from sales of the residue natural gas and NGLs. Certain of these arrangements may also result in returning all or a portion of the residue natural gas and/or the NGLs to the producer, in lieu of returning sales proceeds. The margins earned are directly related to the volume of natural gas that flows through the system and the price at which the Partnership is able to sell the residue natural gas and NGLs. The majority of the Partnership’s contracts have a single performance obligation which is either to provide gathering services (an integrated service) or sell natural gas, NGLs and condensate, which are both satisfied when the related natural gas, crude oil and produced water are received and transferred to an agreed upon delivery point. The Partnership also has certain contracts with multiple performance obligations. They include an option for the customer to acquire additional services such as contracts containing MVCs. These performance obligations would also be satisfied when the related natural gas, crude oil and produced water are received and transferred to an agreed upon delivery point. In these instances, the Partnership allocates the contract’s transaction price to each performance obligation using its best estimate of the standalone selling price of each service in the contract. Performance obligations for gathering services are generally satisfied over time. The Partnership utilizes either an output method (i.e., measure of progress) for guaranteed, stand-ready service contracts or an asset/system delivery time estimate for non-guaranteed, as-available service contracts. Performance obligations for the sale of natural gas, NGLs and condensate are satisfied at a point in time. There are no significant judgments for these transactions because the customer obtains control based on an agreed upon delivery point. Services are typically billed on a monthly basis and the Partnership does not offer extended payment terms. The Partnership does not have contracts with financing components. For the contracts described above, the Partnership reflects its revenues in the financial statement captions described below. Financial statement caption: Revenue description: Revenues: Gathering services and related fees • Revenue earned from fee-based gathering, compression, treating and processing services; Natural gas, NGLs and condensate sales • Revenue from the sale of physical natural gas purchased from customers percent-of- proceeds arrangements (Costs are presented within cost of natural gas and NGLs); • Revenue from sale of condensate and NGLs retained from gathering services (Costs are presented within operation and maintenance expense); Other revenues • Reimbursements to the Partnership for costs incurred by the Partnership on customer’s behalf (Recorded on a gross basis with corresponding costs included in operations and maintenance expense); • Revenue for freshwater deliveries; and • Revenue for management fees related to Double E. Certain of the Partnership’s gathering and/or processing agreements provide for monthly or annual MVCs. Under these MVCs, customers agree to ship and/or process a minimum volume of production on its gathering systems or to pay a minimum monetary amount over certain periods during the term of the MVC. A customer must make a shortfall payment to the Partnership at the end of the contracted measurement period if its actual throughput volumes are less than its contractual MVC for that period. Certain customers are entitled to utilize shortfall payments to offset gathering fees in one or more subsequent contracted measurement periods to the extent that such customers throughput volumes in a subsequent contracted measurement period exceed its MVC for that contracted measurement period. The Partnership recognizes customer obligations under their MVCs as revenue and contract assets when (i) it considers it remote that the customer will utilize shortfall payments to offset gathering or processing fees in excess of its MVCs in subsequent periods; (ii) the customer incurs a shortfall in a contract with no banking mechanism or claw back provision; (iii) the customer’s banking mechanism has expired; or (iv) it is remote that the customer will use its unexercised right. In making this determination, the Partnership considers both quantitative and qualitative facts and circumstances, including, but not limited to, contract terms, capacity of the associated pipeline or receipt point and/or expectations regarding future investment, drilling and production. The majority of the Partnership’s revenue is derived from long-term, fee-based contracts with its customers, which include original terms of up to 25 years. The Partnership recognizes revenue earned from fee-based gathering, compression, treating and processing services in gathering services and related fees. The Partnership also earns revenue in the Rockies, Permian and Piceance reporting segments from the sale of physical natural gas purchased from its customers under certain percent-of-proceeds arrangements. Under ASC Topic 606, these gathering contracts are presented net within cost of natural gas and NGLs. The Partnership sells natural gas that it retains from certain customers in the Barnett reporting segment to offset the power expenses, included in operations and maintenance expense, of the electric-driven compression on the gathering system. The Partnership also sells condensate and NGLs retained from certain of its gathering services in the Piceance and Rockies reporting segments. Revenues from the sale of natural gas and condensate are recognized in Natural gas, NGLs and condensate sales; the associated expense is included in Operation and maintenance expense. Certain customers reimburse the Partnership for costs incurred on their behalf. The Partnership records costs incurred and reimbursed by its customers on a gross basis, with the revenue component recognized in Other revenues and the associated expense included in operations and maintenance expense. The transaction price in the Partnership’s contracts is primarily based on the volume of natural gas, crude oil or produced water transferred by its gathering systems to the customer’s agreed upon delivery point multiplied by the contractual rate. For contracts that include MVCs, variable consideration up to the MVC will be included in the transaction price. For contracts that do not include MVCs, the Partnership does not estimate variable consideration because the performance obligations are completed and settled on a daily basis. For contracts containing noncash consideration such as fuel received in-kind, the Partnership measures the transaction price at the point of sale when the volume, mix and market price of the commodities are known. The Partnership has contracts with MVCs that are variable and constrained. Contracts with longer than monthly MVCs are reviewed on a quarterly basis and adjustments to those estimates are made during each respective reporting period, if necessary. The transaction price is allocated if the contract contains more than one performance obligation such as contracts that include MVCs. The transaction price allocated is based on the MVC for the applicable measurement period. Unit-Based Compensation. For awards of unit-based compensation, the Partnership determines a grant date fair value and recognizes the related compensation expense in the statements of operations over the vesting period for each respective award. Income Taxes. The Partnership is generally not subject to federal and state income taxes, except as noted below. However, its unitholders are individually responsible for paying federal and state income taxes on their share of its taxable income. Net income or loss for GAAP purposes may differ significantly from taxable income reportable to its unitholders as a result of differences between the tax basis and the GAAP basis of assets and liabilities and the taxable income allocation requirements of the Partnership’s governing documents. The aggregate difference in the basis of the Partnership’s net assets for financial and income tax purposes cannot be readily determined as the Partnership does not have access to the information about each partner’s tax attributes related to the Partnership. In general, legal entities that are chartered, organized or conducting business in the state of Texas are subject to a franchise tax (the “Texas Margin Tax”). The Texas Margin Tax has the characteristics of an income tax because it is determined by applying a tax rate to a tax base that considers both revenues and expenses. The Partnership’s financial statements reflect provisions for these tax obligations. Interest Rate Swaps. Interest rate swap agreements are reported as either assets or liabilities on the consolidated balance sheet at fair value. Interest rate swap agreements are not designated as cash-flow hedges, and accordingly, the changes in the fair value are recorded in earnings. The Partnership does not use interest rate swap agreements for speculative purposes. New accounting standards not yet implemented in this Annual Report. ASU No. 2020-06 Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815 – 40) (“ASU 2020-06”). ASU 2020-06 simplifies the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts on an entity’s own equity. The ASU is part of the FASB’s simplification initiative, which aims to reduce unnecessary complexity in GAAP. The ASU’s amendments are effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years. The Partnership does not expect the provisions of ASU 2020-06 will have a material impact on its consolidated financial statements and disclosures. ASU No. 2020-04, Reference Rate Reform (Topic 848) - Facilitation of the Effects of Reference Rate Reform on Financial Reporting (“ASU 2020-04”) and ASU No. 2022-06, Reference Rate Reform (Topic 848) - Deferral of the Sunset Date of Topic 848 (“ASU 2022-06”). ASU 2020-04 and ASU 2022-06 provide optional expedients and exceptions for applying GAAP to contracts, hedging relationships and other transactions affected by reference rate reform on financial reporting. The amendments in ASU 2020-04 and ASU 2022-06 are effective as of March 12, 2020 through December 31, 2024. The Partnership does not expect the provisions of ASU 2020-04 and ASU 2022-06 will have a material impact on its consolidated financial statements and disclosures.

ACQUISTIONS AND DIVESTITURES

ACQUISTIONS AND DIVESTITURES	12 Months Ended
	Dec. 31, 2022
Business Combination and Asset Acquisition [Abstract]
ACQUISTIONS AND DIVESTITURES	3. ACQUISTIONS AND DIVESTITURES Acquisition of Outrigger DJ. On December 1, 2022, the Partnership completed the acquisition of 100% of the equity interests of Outrigger DJ Midstream LLC (“Outrigger DJ”) from Outrigger Energy II LLC for cash consideration of $165.0 million, subject to customary working capital adjustments. The acquisition of Outrigger DJ constituted a business combination and was accounted for using the acquisition method of accounting. For tax purposes, the acquisition was accounted for as an acquisition of assets. The acquisition significantly increased the Partnership’s gas processing capacity and footprint in the DJ Basin and diversified its customer base. The estimated fair values of certain assets and liabilities, including property, plant and equipment and other intangible assets required significant judgements and estimates. As a result, the provisional measurements below are preliminary and subject to change during the measurement period and such changes could be material. The Partnership continues to assess the fair values of the assets acquired and liabilities assumed. The following table sets forth the preliminary fair value of the assets acquired and liabilities assumed as of the acquisition date. Certain data and assessments necessary to complete the purchase price allocation are still under evaluation, including, but not limited to, the final actualization of accrued liabilities and receivable balances and the valuation of property, plant and equipment and intangible assets. The Partnership will finalize the purchase price allocation during the twelve-month period following the acquisition date, during which time the value of the assets and liabilities may be revised as appropriate. (in thousands) Total consideration paid for Outrigger DJ $ 167,631 Recognized amounts of identifiable assets acquired and liabilities assumed: Cash 1,000 Accounts receivable 7,529 Other current assets 190 Property, plant and equipment, net 144,514 Intangible assets 21,447 Trade accounts payable, accrued expenses and other (7,049) Net assets acquired and liabilities assumed $ 167,631 The assets acquired and liabilities assumed were recorded at their preliminary estimated fair values at the date of the acquisition. Acquired working capital amounts are expected to approximate fair value due to their short-term nature. The valuation of certain assets, including property, are based on preliminary appraisals. The fair value of acquired equipment is based on both available market data and cost and income approaches. These methods are considered Level 3 fair value estimates and include significant assumptions of future gathering and processing volumes, commodity prices, and operating and capital cost estimates, discounted using weighted average cost of capital for industry peers. Intangible assets acquired consist of rights-of-way with a weighted average amortization period of 30 years. From the date of the Outrigger DJ Acquisition through December 31, 2022, revenues and operating income associated with the operations acquired through the Outrigger DJ Acquisition totaled $8.4 million and $1.8 million, respectively. Acquisition of Sterling DJ. On December 1, 2022, the Partnership completed the acquisition of 100% of the equity interests in each of Sterling Energy Investments LLC, Grasslands Energy Marketing LLC and Centennial Water Pipelines LLC (collectively, “Sterling DJ”) from Sterling Investment Holdings LLC for cash consideration of $140.0 million, subject to customary working capital adjustments. The acquisition of Sterling DJ constituted a business combination and was accounted for using the acquisition method of accounting. For tax purposes, the acquisition was accounted for as an acquisition of assets. The acquisition significantly increased the Partnership’s gas processing capacity and footprint in the DJ Basin and diversified its customer base. The estimated fair values of certain assets and liabilities, including property, plant and equipment, other intangible assets and contingencies required significant judgements and estimates. As a result, the provisional measurements below are preliminary and subject to change during the measurement period and such changes could be material. The Partnership continues to assess the acquired liabilities of Sterling DJ and ongoing assessments primarily relate to outstanding litigation and other legal compliance matters that existed prior to December 1, 2022. The following table sets forth the preliminary fair value of the assets acquired and liabilities assumed as of the acquisition date. Certain data and assessments necessary to complete the purchase price allocation are still under evaluation, including, but not limited to, the final actualization of accrued liabilities and receivable balances and the valuation of property, plant and equipment and intangible assets. The Partnership will finalize the purchase price allocation during the twelve-month period following the acquisition date, during which time the value of the assets and liabilities may be revised as appropriate. (in thousands) Total consideration paid for Sterling DJ $ 140,396 Recognized amounts of identifiable assets acquired and liabilities assumed: Cash 500 Accounts receivable 16,224 Other current assets 4,557 Property, plant and equipment, net 108,720 Intangible assets 38,678 Other noncurrent assets 9,865 Trade accounts payable, accrued expenses and other (38,148) Net assets acquired $ 140,396 The assets acquired and liabilities assumed were recorded at their preliminary estimated fair values at the date of the acquisition. Acquired working capital amounts are expected to approximate fair value due to their short-term nature. The valuation of certain assets, including property, are based on preliminary appraisals. The fair value of acquired equipment is based on both available market data and cost and income approaches. These methods are considered Level 3 fair value estimates and include significant assumptions of future gathering and processing volumes, commodity prices, and operating and capital cost estimates, discounted using weighted average cost of capital for industry peers. Intangible assets acquired consist of rights-of-way of $30.2 million with a weighted average amortization period of 30 years and indefinite-lived intangible assets of $8.4 million. From the date of the Sterling DJ Acquisition through December 31, 2022, revenues and operating income associated with the operations acquired through the Sterling DJ Acquisition totaled $7.9 million and $0.1 million, respectively. Divestiture of Bison Midstream. On September 19, 2022, the Partnership completed the sale of Bison Midstream, LLC (“Bison Midstream”) and its gas gathering system in Burke and Mountrail Counties, North Dakota to a subsidiary of Steel Reef Infrastructure Corp. (“Steel Reef”), an integrated owner and operator of associated gas capture, gathering and processing assets in North Dakota and Saskatchewan, for cash consideration of $40.0 million, subject to customary working capital adjustments. During the year ended December 31, 2022, the Partnership recognized an impairment of $6.9 million related to the disposition of Bison Midstream based on total cash proceeds received of $38.9 million and net assets disposed of totaling $45.8 million. The cash proceeds received were used to reduce amounts outstanding under the ABL. Divestiture of Lane G&P System. On June 30, 2022, the Partnership completed the sale of Summit Permian, which owns the Lane Gathering and Processing System (“Lane G&P System”), and Permian Finance to Longwood Gathering and Disposal Systems, LP (“Longwood”), a wholly owned subsidiary of Matador ͏Resources Company (“Matador”), for cash consideration of $75.0 million, subject to customary working capital adjustments. In connection with the transaction, the Partnership released, to a subsidiary of Matador, and Matador agreed to assume, take or-pay firm capacity on the Double E Pipeline. During the year ended December 31, 2022, the Partnership recognized an impairment of $84.5 million related to the disposition of the Lane G&P System based on total cash proceeds received of $75.0 million, including $2.0 million of cash sold in the transaction, adjusted net assets of $158.3 million, and other costs to sell of $1.2 million. The cash proceeds received were used to reduce amounts outstanding under the ABL Facility. Pro Forma Information (Unaudited). The following table summarizes the unaudited pro forma condensed financial information of SMLP as if the acquisitions of Outrigger DJ and Sterling DJ, along with the dispositions of Bison Midstream and the Lane G&P System, had occurred on January 1, 2021: Year Ended Year Ended Revenues $ 543,024 $ 471,787 Net loss $ (36,945) $ (35,396) The unaudited pro forma information is for informational purposes only and is not necessarily indicative of the operating results that would have occurred had the transactions been completed at January 1, 2021, nor is it necessarily indicative of future operating results. The financial data was adjusted to give effect to pro forma events that are i) directly attributable to the transactions, ii) factually supportable, and iii) expected to have a continuing impact on the consolidated results of operations. Significant adjustments to the pro forma information above include adjustments to interest expense and depreciation based on the purchase price allocated to property, plant, and equipment.

REVENUE

REVENUE	12 Months Ended
	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
REVENUE	4. REVENUE The following table presents estimated revenue expected to be recognized over the remaining contract period related to performance obligations that are unsatisfied and are comprised of estimated MVC shortfall payments. The Partnership applies the practical expedient in paragraph 606-10-50-14 of Topic 606 for certain arrangements that are considered optional purchases (i.e., there is no enforceable obligation for the customer to make purchases) and those amounts are therefore excluded from the table. 2023 2024 2025 2026 2027 Thereafter (in thousands) Gathering services and related fees $ 78,245 $ 67,079 $ 46,803 $ 30,527 $ 9,038 $ 6,042 Revenue by Category . In the following table, revenue is disaggregated by geographic area and major products and services. For more detailed information about reportable segments, see Note 17 -Segment Information. Year ended December 31, 2022 Gathering services and related fees Natural gas, NGLs and condensate sales Other revenues Total (in thousands) Reportable Segments: Northeast $ 54,392 $ — $ — $ 54,392 Rockies 67,838 59,208 16,557 143,603 Permian 3,668 17,382 4,101 25,151 Piceance 80,630 7,111 5,608 93,349 Barnett 41,830 2,503 7,763 52,096 Total reportable segments 248,358 86,204 34,029 368,591 Corporate and other — 21 982 1,003 Total $ 248,358 $ 86,225 $ 35,011 $ 369,594 Year ended December 31, 2021 Gathering services and related fees Natural gas, NGLs and condensate sales Other revenues Total (in thousands) Reportable Segments: Northeast $ 62,567 $ — $ — $ 62,567 Rockies 74,823 48,279 21,985 145,087 Permian 8,230 28,727 3,891 40,848 Piceance 95,235 5,464 4,786 105,485 Barnett 40,850 298 5,443 46,591 Total reportable segments 281,705 82,768 36,105 400,578 Corporate and other — — 40 40 Total $ 281,705 $ 82,768 $ 36,145 $ 400,618

PROPERTY, PLANT, AND EQUIPMENT

PROPERTY, PLANT, AND EQUIPMENT	12 Months Ended
	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
PROPERTY, PLANT, AND EQUIPMENT	5. PROPERTY, PLANT AND EQUIPMENT Details on the Partnership’s property, plant and equipment follow. December 31, 2022 December 31, 2021 (In thousands) Gathering and processing systems and related equipment $ 2,262,330 $ 2,225,267 Construction in progress 59,036 49,082 Land and line fill 11,756 10,644 Other 62,222 51,863 Total 2,395,344 2,336,856 Less accumulated depreciation (676,590) (610,774) Property, plant and equipment, net $ 1,718,754 $ 1,726,082 When the carrying amount of a long-lived asset is not recoverable, an impairment is recognized equal to the excess of the asset’s carrying value over its fair value, which is based on inputs that are not observable in the market, and thus represent Level 3 inputs under GAAP’s fair value hierarchy. The Partnership recognized $91.6 million and $10.2 million of impairments during the fiscal years ended December 31, 2022 and 2021, respectively. The Partnership cannot predict the likelihood of future impairments, if any. Depreciation expense and capitalized interest for the Partnership follow. Year ended December 31, 2022 2021 (In thousands) Depreciation expense $ 93,457 $ 90,711 Capitalized interest 838 $ 1,534

INTANGIBLE ASSETS

INTANGIBLE ASSETS	12 Months Ended
	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
INTANGIBLE ASSETS	6. INTANGIBLE ASSETS Details regarding the Partnership’s intangible assets follow. December 31, 2022 Gross carrying amount Accumulated amortization Net (In thousands) Favorable gas gathering contracts $ 21,063 $ (14,809) $ 6,254 Contract intangibles 270,412 (228,143) 42,269 Rights-of-way 200,089 (58,330) 141,759 Indefinite-lived intangibles 8,436 — 8,436 Total intangible assets $ 500,000 $ (301,282) $ 198,718 December 31, 2021 Gross carrying amount Accumulated amortization Net (In thousands) Favorable gas gathering contracts $ 24,195 $ (17,002) $ 7,193 Contract intangibles 278,448 (217,245) 61,203 Rights-of-way 159,916 (55,385) 104,531 Total intangible assets $ 462,559 $ (289,632) $ 172,927 The Partnership recognized amortization expense of its favorable gas gathering contracts in Other revenues as follows: Year ended December 31, 2022 2021 (In thousands) Amortization expense – favorable gas gathering contracts $ 938 $ 938 The Partnership recognized amortization expense of its contract and right of way intangibles in costs and expenses as follows: Year ended December 31, 2022 2021 (In thousands) Amortization expense – contract intangibles $ 18,935 $ 22,002 Amortization expense – rights-of-way 6,527 6,344 The Partnership’s estimated aggregate annual amortization expected to be recognized for each of the five succeeding fiscal years and thereafter, as of December 31, 2022, follows. (In thousands) 2023 $ 27,749 2024 17,563 2025 17,379 2026 14,354 2027 8,365 Thereafter 104,872 $ 190,282

EQUITY METHOD INVESTMENTS

EQUITY METHOD INVESTMENTS	12 Months Ended
	Dec. 31, 2022
Equity Method Investments and Joint Ventures [Abstract]
EQUITY METHOD INVESTMENTS	7. EQUITY METHOD INVESTMENTS The Partnership has equity method investments in Double E and Ohio Gathering, the balances of which are included in the Investment in equity method investees caption on the consolidated balance sheets. Details of the Partnership’s equity method investments follows. December 31, 2022 December 31, 2021 (In thousands) Double E $ 281,640 $ 280,952 Ohio Gathering 225,037 242,244 Total $ 506,677 $ 523,196 Double E. The Partnership, through its wholly owned subsidiary Summit Permian Transmission, LLC, has a 70% ownership in Double E Pipeline, LLC (the “Double E”). Double E owns a long-haul natural gas pipeline (the “Double E Pipeline”) that provides transportation service for residue natural gas from multiple receipt points in the Delaware Basin to various delivery points in and around the Waha hub in Texas. The Double E Pipeline commenced operations in November 2021 and during the years ended December 31, 2022 and 2021, the Partnership made cash investments of $8.4 million and $148.7 million, respectively, in Double E, with such amounts including nil and $3.0 million of capitalized interest, respectively. During the year ended December 31, 2022, Double E made distributions to its investors totaling $17.8 million of which the Partnership received $12.5 million, of which all amounts were utilized for payment of interest and principal on the Permian Transmission Term Loan and distributions to the holders of the Subsidiary Series A Preferred Units. Double E is deemed to be a variable interest entity as defined in GAAP. Summit Permian Transmission was not deemed to be the primary beneficiary of Double E due to the voting rights of Double E’s other owner regarding significant matters. The Partnership accounts for its ownership interest in Double E as an equity method investment because it has significant influence over Double E. Summarized balance sheet information for Double E follows (amounts represent 100% of investee financial information). December 31, 2022 December 31, 2021 (In thousands) Current assets $ 5,121 $ 12,353 Noncurrent assets 403,594 410,731 Total assets $ 408,715 $ 423,084 Current liabilities $ 8,635 $ 22,836 Noncurrent liabilities 9,137 10,281 Total liabilities $ 17,772 $ 33,117 Summarized statements of operations information for Double E follows (amounts represent 100% of investee financial information). Year Ended December 31, 2022 Year Ended December 31, 2021 (In thousands) Total revenues $ 32,418 $ 3,579 Total operating expenses 25,685 5,281 Net income (loss) $ 6,733 $ (1,702) At December 31, 2022 and 2021, the Partnership’s carrying amount of its interest in Double E approximated its underlying investment. Ohio Gathering. The Partnership has investments in OGC and OCC that are collectively referred to as Ohio Gathering. Ohio Gathering owns, operates and is currently developing midstream infrastructure consisting of a liquids-rich natural gas gathering system, a dry natural gas gathering system and a condensate stabilization facility in the Utica Shale in southeastern Ohio. Ohio Gathering provides gathering services pursuant to primarily long-term, fee-based gathering agreements, which include acreage dedications. The Partnership made its initial investment in Ohio Gathering in 2014 and owned approximately 37.2% of OGC and approximately 38.2% of OCC at December 31, 2022 and approximately 37.8% of OGC and approximately 38.2% of OCC at December 31, 2021. Ohio Gathering is accounted for as an equity method investment because it has joint control with non-affiliated owners, which gives the Partnership significant influence. A reconciliation of the difference between the carrying amount of the Partnership’s interest in Ohio Gathering and the Partnership’s underlying investment in Ohio Gathering, per Ohio Gathering’s books and records, is shown below. 2022 2021 (In thousands) Investment in Ohio Gathering, December 31 $ 225,037 $ 242,244 December cash distributions 2,673 2,222 Impairment loss — 1,971 Basis difference 199,263 207,927 Other — 137 Investment in Ohio Gathering (Books and records), November 30, $ 426,973 $ 454,501 Summarized balance sheet information for OGC and OCC follows (amounts represent 100% of investee financial information). November 30, 2022 November 30, 2021 OGC OCC OGC OCC (In thousands) Current assets $ 36,062 $ 5,195 $ 36,967 $ 5,300 Noncurrent assets 1,157,530 274 1,189,921 961 Total assets $ 1,193,592 $ 5,469 $ 1,226,888 $ 6,261 Current liabilities $ 6,942 $ 3,588 $ 7,984 $ 3,104 Noncurrent liabilities 13,380 3,096 9,854 4,927 Total liabilities $ 20,322 $ 6,684 $ 17,838 $ 8,031 Summarized statements of operations information for OGC and OCC follows (amounts represent 100% of investee financial information). Twelve months ended Twelve months ended OGC OCC OGC OCC (In thousands) Total revenues $ 113,317 $ 13,340 $ 102,140 $ 12,614 Total operating expenses 106,369 12,786 95,399 11,419 Net income (loss) 6,948 554 6,742 1,169

DEFERRED REVENUE

DEFERRED REVENUE	12 Months Ended
	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
DEFERRED REVENUE	8. DEFERRED REVENUE Certain of the Partnership’s gathering and/or processing agreements provide for monthly or annual MVCs. The amount of the shortfall payment is based on the difference between the actual throughput volume shipped and/or processed for the applicable period and the MVC for the applicable period, multiplied by the applicable gathering or processing fee. Many of the Partnership’s gas gathering agreements contain provisions that can reduce or delay the cash flows that it expects to receive from MVCs to the extent that a customer's actual throughput volumes are above or below its MVC for the applicable contracted measurement period. These provisions include the following: • To the extent that a customer's throughput volumes are less than its MVC for the applicable period and the customer makes a shortfall payment, it may be entitled to an offset in one or more subsequent periods to the extent that its throughput volumes in subsequent periods exceed its MVC for those periods. In such a situation, the Partnership would not receive gathering fees on throughput in excess of that customer's MVC (depending on the terms of the specific gas gathering agreement) to the extent that the customer had made a shortfall payment with respect to one or more preceding measurement periods (as applicable). • To the extent that a customer's throughput volumes exceed its MVC in the applicable contracted measurement period, it may be entitled to apply the excess throughput against its aggregate MVC, thereby reducing the period for which its annual MVC applies. As a result of this mechanism, the weighted-average remaining period for which the Partnership’s MVCs apply will be less than the weighted-average of the originally stated MVC contractual terms. • To the extent that certain of the Partnership’s customers' throughput volumes exceed its MVC for the applicable period, there is a crediting mechanism that allows the customer to build a bank of credits that it can utilize in the future to reduce shortfall payments owed in subsequent periods, subject to expiration if there is no shortfall in subsequent periods. The period over which this credit bank can be applied to future shortfall payments varies, depending on the particular gas gathering agreement. The balances in deferred revenue as of December 31, 2022 and 2021 are primarily related to contributions in aid of construction which will be recognized as revenue over the life of the contract. An update of current deferred revenue is as follows. (In thousands) Current deferred revenue, January 1, 2022 $ 10,374 Additions 4,578 Less: revenue recognized (5,898) Current deferred revenue, December 31, 2022 $ 9,054 An update of noncurrent deferred revenue follows. (In thousands) Noncurrent deferred revenue, January 1, 2022 $ 42,570 Additions 269 Less: reclassification to current deferred revenue and other (5,145) Noncurrent deferred revenue, December 31, 2022 $ 37,694

DEBT

DEBT	12 Months Ended
	Dec. 31, 2022
Debt Disclosure [Abstract]
DEBT	9. DEBT Debt for the Partnership at December 31, 2022 and 2021 follows. December 31, 2022 December 31, 2021 (In thousands) ABL Facility : Summit Holdings' asset based credit facility due May 1, 2026 $ 330,000 $ 267,000 Permian Transmission Credit Facility : Permian Transmission's variable rate senior secured credit facility due March 8, 2028 — 160,000 Permian Transmission Term Loan : Permian Transmission's variable rate senior secured term loan due January 2028 155,353 — 2025 Senior Notes : Summit Holdings' 5.75% senior unsecured notes due April 15, 2025 259,463 259,463 2026 Secured Notes : Summit Holdings' and Finance Corp's 8.50% senior second lien notes due October 15, 2026 785,000 700,000 Less: unamortized debt discount and debt issuance costs (39,454) (31,391) Total debt 1,490,362 1,355,072 Less: current portion of Permian Transmission Credit Facility (10,507) — Total long-term debt $ 1,479,855 $ 1,355,072 The aggregate amount of Partnership’s debt maturing during each of the years after December 31, 2022 are as follows (in thousands): 2023 $ 10,507 2024 15,524 2025 276,043 2026 1,131,967 2027 17,769 Thereafter 78,006 Total long-term debt $ 1,529,816 ABL Facility. On November 2, 2021, the Partnership, the Partnership’s subsidiary, Summit Holdings, and the subsidiaries of Summit Holdings party thereto entered into a first-lien, senior secured credit facility, consisting of a $400.0 million asset-based revolving credit facility (the “ABL Facility”), subject to a borrowing base comprised of a percentage of eligible accounts receivable of Summit Holdings and its subsidiaries that guarantee the ABL Facility (collectively, the “ABL Facility Subsidiary Guarantors”) and a percentage of eligible above-ground fixed assets including eligible compression units, processing plants, compression stations and related equipment of Summit Holdings and the ABL Facility Subsidiary Guarantors. As of December 31, 2022, the most recent borrowing base determination of eligible assets totaled $561.0 million, an amount greater than the $400.0 million of aggregate commitments. On October 14, 2022, we amended the ABL Facility to, among other things, transition the LIBOR based interest rates under the ABL Facility to term secured overnight financing rates (“SOFR”). As of December 31, 2022, the applicable margin under the adjusted term SOFR borrowings was 3.25%, the interest rate was 7.45% and the unused portion of the ABL Facility totaled $64.1 million after giving effect to the issuance of $5.9 million in outstanding but undrawn irrevocable standby letters of credit. Summit Holdings entered into that certain Loan and Security Agreement governing the ABL Facility (the “ABL Agreement”), dated as of November 2, 2021, by and among Summit Holdings, as borrower, the Partnership, the ABL Facility Subsidiary Guarantors, Bank of America, N.A., as agent, ING Capital LLC, Royal Bank of Canada and Regions Bank, as co-syndication agents, and Bank of America, N.A., ING Capital LLC, RBC Capital Markets and Regions Capital Markets, as joint lead arrangers and joint bookrunners. The ABL Facility will mature on May 1, 2026; provided that, (a) if the outstanding amount of the 2025 Senior Notes (or any permitted refinancing indebtedness in respect thereof that has a final maturity, scheduled amortization or any other scheduled repayment, mandatory prepayment, mandatory redemption or sinking fund obligation prior to the date that is 120 days after the Termination Date (as defined in the ABL Agreement)) on such date equals or exceeds $50.0 million, then the ABL Facility will mature on December 13, 2024 and (b) if both (i) any amount of the 2025 Senior Notes (or any permitted refinancing indebtedness in respect thereof that has a final maturity, scheduled amortization or any other scheduled repayment, mandatory prepayment, mandatory redemption or sinking fund obligation prior to the date that is 120 days after the Termination Date) is outstanding on such date and (ii) Liquidity (as defined in the ABL Agreement) is less than an amount equal to the sum of the then aggregate outstanding principal amount of the 2025 Senior Notes (or any permitted refinancing indebtedness in respect thereof that has a final maturity, scheduled amortization or any other scheduled repayment, mandatory prepayment, mandatory redemption or sinking fund obligation prior to the date that is 120 days after the Termination Date) plus the Threshold Amount (as defined in the ABL Agreement) on such date, then the ABL Facility will mature on January 14, 2025. The ABL Facility (together with certain Secured Bank Product Obligations (as defined in the ABL Agreement)) will be jointly and severally guaranteed, on a senior first-priority secured basis (subject to permitted liens), by the Partnership, Summit Holdings and each of the ABL Facility Subsidiary Guarantors. The ABL Facility restricts, among other things, Summit Holdings’ and its Restricted Subsidiaries’ (as defined in the ABL Agreement) ability and the ability of certain of their subsidiaries to: (i) incur additional debt or issue preferred stock; (ii) make distributions or repurchase equity; (iii) make payments on or redeem junior lien, unsecured or subordinated indebtedness; (iv) create liens or other encumbrances; (v) make investments, loans or other guarantees; (vi) engage in transactions with affiliates; and (viii) make acquisitions or merge or consolidate with another entity. These covenants are subject both to a number of important exceptions and qualifications. The ABL Facility requires that Summit Holdings not permit (i) the First Lien Net Leverage Ratio (as defined in the ABL Agreement) as of the last day of any fiscal quarter to be greater than 2.50:1.00, or (ii) the Interest Coverage Ratio (as defined in the ABL Agreement) as of the last day of any fiscal quarter to be less than 2.00:1.00. As of December 31, 2022, the First Lien Net Leverage Ratio was 1.31:1.00 and the Interest Coverage Ratio was 2.52:1.00 and the Partnership was in compliance with the financial covenants of the ABL Facility. The ABL Facility contains certain events of default customary for instruments of this type. In the case of an event of default arising from certain events of bankruptcy, insolvency or reorganization with respect to Summit Holdings, all outstanding Obligations (as defined in the ABL Agreement) will become due and payable immediately without further action or notice and all commitments under the ABL Facility will terminate. Pursuant to the ABL Agreement, the Obligations (as defined in the ABL Agreement) are (or, subject to post-closing periods for certain types of collateral, will be) generally secured by a first priority lien on and security interest in (subject to permitted liens), subject to certain exclusions and limitations set forth in the ABL Agreement, (i) substantially all of the personal property of Summit Holdings and the ABL Facility Subsidiary Guarantors, (ii) all equity interests in Summit Holdings and certain other entities, all debt securities and certain rights related to the foregoing, in each case, owned by the Partnership, (iii) Closing Date Material Gathering Station Real Property and Closing Date Pipeline Material Gathering Station Real Property (each, as defined in the ABL Agreement) and certain other material real property interests (including improvements thereon) of Summit Holdings and the ABL Facility Subsidiary Guarantors as provided in the ABL Agreement and (iv) all proceeds of the foregoing collateral . Intercreditor Agreement. On November 2, 2021, in connection with the entry into the ABL Facility and issuance of the 2026 Secured Notes, Summit Holdings and the other guarantors party thereto entered into an Intercreditor Agreement (the “Intercreditor Agreement”) with Bank of America, N.A., as first lien representative and collateral agent for the initial first lien claimholders, Regions Bank, as second lien representative for the initial second lien claimholders and collateral agent for the initial second lien claimholders, establishing (i) a first-priority lien (subject to permitted liens) status for the liens on the collateral securing the ABL Facility and any additional first-lien indebtedness and (ii) a junior priority lien (subject to permitted liens) status for the liens on the collateral securing the 2026 Secured Notes and any additional second-lien indebtedness. Permian Transmission Credit Facility. On March 8, 2021 (the “Permian Closing Date”), the Partnership’s unrestricted subsidiary, Permian Transmission, entered into a Credit Agreement which allows for $175.0 million of senior secured credit facilities (the “Permian Transmission Credit Facilities”), including a $160.0 million Term Loan Facility and a $15.0 million Working Capital Facility. The Permian Transmission Credit Facilities can be used to finance Permian Transmission’s capital calls associated with its investment in Double E, debt service and other general corporate purposes. Unexpended proceeds from draws on the Permian Transmission Credit Facilities are classified as restricted cash on the accompanying unaudited condensed consolidated balance sheets. As of December 31, 2022, the applicable margin under adjusted LIBOR borrowings was 2.375%, the interest rate was 6.05% and the unused portion of the Permian Transmission Credit Facilities totaled $4.5 million, subject to a commitment fee of 0.7% after giving effect to the issuance of $10.5 million in outstanding but undrawn irrevocable standby letters of credit. Summit Permian Transmission, LLC entered into interest rate hedges with notional amounts representing approximately 90% of the Permian Term Loan facility at a fixed LIBOR rate of 1.49%. As of December 31, 2022, the Partnership was in compliance with the financial covenants of the Permian Transmission Credit Facilities. Permian Transmission Term Loan. As described above, in January 2022, the Permian Term Loan Facility was converted into a Term Loan (the “Permian Transmission Term Loan”). The Permian Transmission Term Loan is due January 2028. As of December 31, 2022, the applicable margin under adjusted LIBOR borrowings was 2.375% and the interest rate was 6.05%. As of December 31, 2022, the Partnership was in compliance with the financial covenants governing the Permian Transmission Term Loan. In accordance with the terms of the Permian Transmission Term Loan, Permian Transmission is required to make mandatory principal repayments. Below is a summary of the remaining mandatory principal repayments as of December 31, 2022: (In thousands) Total 2023 2024 2025 2026 2027 Thereafter Amortizing principal repayments $ 155,353 $ 10,507 $ 15,524 $ 16,580 $ 16,967 $ 17,769 $ 78,006 2026 Secured Notes. In 2021, the Co-Issuers issued $700.0 million of 8.500% Senior Secured Second Lien Notes due 2026 (the “2026 Secured Notes”) to eligible purchasers pursuant to Rule 144A and Regulation S of the Securities Act, at a price of 98.5% of their face value. Additionally, in November 2022, in connection with the 2022 DJ Acquisitions, the Co-Issuers issued an additional $85.0 million of 2026 Secured Notes at a price of 99.26% of their face value. The 2026 Secured Notes will pay interest semi-annually on April 15 and October 15 of each year, commencing on April 15, 2022, and are jointly and severally guaranteed, on a senior second-priority secured basis (subject to permitted liens), by the Partnership and each restricted subsidiary of the Partnership (other than the Co-Issuers) that is an obligor under the ABL Agreement, or under the Co-Issuers’ 2025 Senior Notes on the issue date of the 2026 Secured Notes. The 2026 Secured Notes will mature on October 15, 2026; provided that, if the outstanding amount of the 2025 Senior Notes (or any refinancing indebtedness in respect thereof that has a final maturity on or prior to the date that is 91 days after the Initial Maturity Date (as defined in the 2026 Secured Notes Indenture)) is greater than or equal to $50.0 million on January 14, 2025, which is 91 days prior to the scheduled maturity date of the 2025 Senior Notes, then the 2026 Secured Notes will mature on January 14, 2025. The Partnership used the net proceeds from the offering of the 2026 Secured Notes, together with cash on hand and borrowings under the ABL Facility, to repay in full all of Summit Holdings’ obligations under the Revolving Credit Facility. 2026 Secured Notes Indenture. The Co-Issuers issued the 2026 Secured Notes pursuant to an indenture (the “2026 Secured Notes Indenture”), dated as of November 2, 2021, by and among the Co-Issuers, the Partnership, any other Restricted Subsidiary (as defined in the 2026 Secured Notes Indenture) of the Partnership that provides a Notes Guarantee (as defined in the 2026 Secured Notes Indenture) and Regions Bank, as trustee (the “Trustee”) and collateral agent, setting forth specific terms applicable to the 2026 Secured Notes. At any time prior to October 15, 2023, the Co-Issuers may on any one or more occasions redeem up to 35% of the aggregate principal amount of the 2026 Secured Notes (including any additional notes) issued under the 2026 Secured Notes Indenture at a redemption price of 108.5% of the principal amount of the 2026 Secured Notes, plus accrued and unpaid interest, if any, to, but not including, the redemption date, in an amount not greater than the net cash proceeds of certain equity offerings by the Partnership, provided that: (i) at least 65% of the initial aggregate principal amount of the 2026 Secured Notes (including any additional notes) remains outstanding immediately after the occurrence of such redemption (excluding notes held by the Partnership and its subsidiaries); and (ii) the redemption occurs within 180 days of the date of the closing of each such equity offering by the Partnership. On and after October 15, 2023, the Co-Issuers may redeem all or part of the 2026 Secured Notes at redemption prices (expressed as percentages of principal amount) equal to: (a) 104.250% for the twelve-month period beginning October 15, 2023; (b) 102.125% for the twelve-month period beginning October 15, 2024; and (c) 100.000% for the twelve-month period beginning on October 15, 2025 and at any time thereafter, in each case plus accrued and unpaid interest, if any, to, but not including, the redemption date. In certain circumstances, the Co-Issuers will be required to offer to purchase the 2026 Secured Notes with excess proceeds from asset sales, excess cash flow and upon the occurrence of certain change of control events. The 2026 Secured Notes Indenture restricts the Partnership’s and its Restricted Subsidiaries’ ability and the ability of certain of their subsidiaries to: (i) incur additional debt or issue preferred stock; (ii) make distributions, repurchase equity or redeem junior lien, unsecured or subordinated debt; (iii) make payments on junior lien, unsecured or subordinated indebtedness; (iv) create liens or other encumbrances; (v) make investments, loans or other guarantees; (vi) engage in transactions with affiliates; and (viii) make acquisitions or merge or consolidate with another entity. These covenants are subject both to a number of important exceptions and qualifications. At any time when the 2026 Secured Notes are rated investment grade by at least two of Moody’s Investors Service, Inc., Standard & Poor’s Ratings Services or Fitch Ratings, Inc., many of these covenants will terminate. As of December 31, 2022, the Partnership was in compliance with the financial covenants of the 2026 Secured Notes. The 2026 Secured Notes Indenture contains certain events of default customary for instruments of this type. In the case of an event of default arising from certain events of bankruptcy, insolvency or reorganization with respect to either Co-Issuer, the Partnership, and certain significant subsidiaries of the Partnership, all outstanding Notes will become due and payable immediately without further action or notice. If any other event of default occurs and is continuing, the Trustee or the holders of at least 25% in principal amount of the then outstanding Notes may declare all the 2026 Secured Notes to be due and payable immediately. Collateral Agreement. On November 2, 2021, the Co-Issuers, as pledgors and grantors, entered into, in connection with the 2026 Secured Notes Indenture, a Collateral Agreement (Second Lien), with the Partnership, as a pledgor, each subsidiary guarantor listed therein and Regions Bank, as collateral agent (the “Collateral Agreement”). Pursuant to the Collateral Agreement and the 2026 Secured Notes Indenture, the obligations under the 2026 Secured Notes Indenture are (or, subject to post-closing periods for certain types of collateral, will be) generally secured by a second priority lien on and security interest in (subject to permitted liens) the assets of the Partnership, the Co-Issuers and the subsidiary guarantors securing their obligations under the ABL Facility (as described above under “ABL Facility”). Excess Cash Flow Offers to Purchase. Starting in the first quarter of 2023 with respect to the fiscal year ended 2022, and continuing annually through the fiscal year 2025, the Partnership is required under the terms of the 2026 Secured Notes Indenture to, if it has Excess Cash Flow (as defined in the 2026 Secured Notes Indenture), and subject to its ability to make such an offer under the ABL Facility, offer to purchase an amount of the 2026 Secured Notes, at 100% of the principal amount plus accrued and unpaid interest, equal to 100% of the Excess Cash Flow generated in the prior year. Excess Cash Flow is generally defined as consolidated cash flow minus the sum of capital expenditures and cash payments in respect of permitted investments and permitted restricted payments. Generally, if the Partnership does not offer to purchase designated annual amounts of its 2026 Secured Notes or reduce its first lien capacity under the 2026 Secured Notes Indenture per annum from 2023 through 2025, the interest rate on the 2026 Secured Notes is subject to certain rate escalations. Per the terms of the 2026 Secured Notes Indenture, the designated amounts are to offer to purchase $50.0 million aggregate principal amount of the 2026 Secured Notes by April 1, 2023, otherwise the interest rate shall automatically increase by 50 basis points per annum; $100.0 million aggregate principal amount of the 2026 Secured Notes by April 1, 2024, otherwise the interest rate shall automatically increase by 100 basis points per annum (minus any amount previously increased); and $200.0 million aggregate principal amount of the 2026 Secured Notes by April 1, 2025, otherwise the interest rate shall automatically increase by 200 basis points per annum (minus any amount previously increased). Based on the amount of the Partnership’s Excess Cash Flow for the fiscal year ended 2022, the Partnership does not anticipate making offers to purchase in the designated amount for the fiscal year ended 2022; and as a result, the interest rate on the 2026 Secured Notes will increase 50 basis points to 9.00% effective April 1, 2023, resulting in increased annual interest expense of approximately $3.9 million. To the extent the Partnership makes an offer to purchase, and the offer is not fully accepted by the holders of the 2026 Secured Notes, the Partnership may use any remaining amount not accepted for any purpose not prohibited by the 2026 Secured Notes Indenture or the ABL Facility. 2025 Senior Notes. In February 2017, the Co-Issuers co-issued the 2025 Senior Notes. The Partnership pays interest on the 2025 Senior Notes semi-annually in cash in arrears on April 15 and October 15 of each year. The 2025 Senior Notes are senior, unsecured obligations and rank equally in right of payment with all of the Partnership’s existing and future senior obligations. The 2025 Senior Notes are effectively subordinated in right of payment to all of the Partnership’s secured indebtedness, to the extent of the collateral securing such indebtedness. The Co-Issuers have the right to redeem all or part of the 2025 Senior Notes at a redemption price of 101.438% (with the redemption price declining ratably each year to 100.00% on April 15, 2023), plus accrued and unpaid interest, if any, to, but not including, the redemption date.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	10. COMMITMENTS AND CONTINGENCIES Environmental Matters. Although the Partnership believes that it is in material compliance with applicable environmental regulations, the risk of environmental remediation costs and liabilities are inherent in pipeline ownership and operation. Furthermore, the Partnership can provide no assurances that significant environmental remediation costs and liabilities will not be incurred in the future. The Partnership is currently not aware of any material contingent liabilities that exist with respect to environmental matters, except as noted below. As of December 31, 2022, the Partnership has recognized (i) a current liability for remediation effort expenditures expected to be incurred within the next 12 months and (ii) a noncurrent liability for estimated remediation expenditures expected to be incurred subsequent to December 31, 2022. Each of these amounts represent the Partnership’s best estimate for costs expected to be incurred. Neither of these amounts have been discounted to its present value. A rollforward of the Partnership’s undiscounted accrued environmental remediation follows and is primarily related to the 2015 Blacktail Release and other environmental remediation activities. (In thousands) Accrued environmental remediation, December 31, 2020 $ 2,929 Payments made (1,972) Additional accruals 4,649 Accrued environmental remediation, December 31, 2021 $ 5,606 Payments made (2,746) Additional accruals 845 Accrued environmental remediation, December 31, 2022 $ 3,705 In 2015, the Partnership learned of the rupture of a four-inch produced water gathering pipeline on the Meadowlark Midstream system near Williston, North Dakota (“2015 Blacktail Release”). On August 4, 2021, subsidiaries of the Partnership entered into the following agreements to resolve the U.S. federal and North Dakota state governments’ environmental claims with respect to the 2015 Blacktail Release: (i) a Consent Decree with the U.S. Department of Justice (“DOJ”), the U.S. Environmental Protection Agency (“EPA”), and the State of North Dakota (“Consent Decree”); (ii) a Plea Agreement with the United States (“Plea Agreement”); and (iii) a Consent Agreement with the North Dakota Industrial Commission (“Consent Agreement” together with the Consent Decree and Plea Agreement, the “Global Settlement”). As of December 31, 2022 and 2021, the accrued loss liability for the 2015 Blacktail Release was $28.3 million and $33.2 million, respectively. Key terms of the Global Settlement included (i) payment of penalties and fines totaling $36.3 million, consisting of $1.25 million in natural resource damages payable to federal and state governments, a $25.0 million payable to the federal government over five years, and a $10.0 million payable to state governments over six years, with interest applied to unpaid amounts accruing at a fixed rate of 3.25%, and of which $6.7 million is expected to be paid within the next twelve months; (ii) continuation of remediation efforts at the site of the 2015 Blacktail Release; (iii) other injunctive relief including but not limited to control room management, environmental management system audit, training, and reporting; (iv) guilty pleas by Defendant subsidiary for (a) one charge of negligent discharge of a harmful quantity of oil and (b) one charge of knowing failure to immediately report a discharge of oil; and (v) organizational probation for a minimum period of three years from sentencing, including payment in full of certain components of the fines and penalty amounts. The agreements comprising the Global Settlement were subject to the approval of the U.S. District Court for the District of North Dakota (the “U.S. District Court”). The U.S. District Court entered an order making the civil components of the Global Settlement effective on September 28, 2021. The U.S. District Court accepted the Plea Agreement on December 6, 2021, and approval of the Global Settlement is now complete. Subsidiaries of the Partnership are also participating in two proceedings before the EPA as a result of the Plea Agreement becoming effective. Following the U.S. District Court’s entering judgment on Defendant subsidiary’s guilty plea to one count of negligent discharge of produced water in violation of the Clean Water Act, Defendant subsidiary was statutorily debarred by operation of law pursuant to 33 U.S.C. § 1368(a) to participate in federal awards performed at the “violating facility,” which EPA determined to be the Marmon subsystem of the produced water gathering system in North Dakota. The scope and effect of the debarment as defined do not materially affect our operations. Defendant has submitted a petition for reinstatement, which was denied by the EPA’s suspension and debarment office (“SDO”) on July 11, 2022. The SDO determined that the term of probation in the Plea Agreement was the appropriate period of time to demonstrate Defendant subsidiary’s change of corporate attitude, policies, practices, and procedures. The Partnership and certain subsidiaries have also received a show cause notice from the EPA requesting us to “show cause” why SDO should not issue a Notice of Proposed Debarment to the Defendant subsidiary and certain affiliates under 2 C.F.R. § 180.800(d), to which we have responded. Legal Proceedings. The Partnership is involved in various litigation and administrative proceedings arising in the normal course of business. In the opinion of management, any liabilities that may result from these claims or those arising in the normal course of business would not individually or in the aggregate have a material adverse effect on the Partnership's financial position or results of operations. As a result of the Sterling DJ acquisition, the Partnership assumed an appeal bond outstanding in the amount of $3.9 million related to a litigation matter outstanding prior to December 1, 2022.

FINANCIAL INSTRUMENTS

FINANCIAL INSTRUMENTS	12 Months Ended
	Dec. 31, 2022
Fair Value Disclosures [Abstract]
FINANCIAL INSTRUMENTS	11. FINANCIAL INSTRUMENTS Concentrations of Credit Risk. Financial instruments that potentially subject the Partnership to concentrations of credit risk consist of cash and cash equivalents, restricted cash and accounts receivable. The Partnership maintains its cash and cash equivalents and restricted cash in bank deposit accounts that frequently exceed federally insured limits. The Partnership has not experienced any losses in such accounts and does not believe it is exposed to any significant risk. Accounts receivable primarily comprise amounts due for the gathering, compression, treating and processing services the Partnership provides to its customers and also the sale of natural gas liquids resulting from its processing services. This industry concentration has the potential to impact its overall exposure to credit risk, either positively or negatively, in that the Partnership’s customers may be similarly affected by changes in economic, industry or other conditions. The Partnership monitors the creditworthiness of its counterparties and can require letters of credit or other forms of credit assurance for receivables from counterparties that are judged to have substandard credit, unless the credit risk can otherwise be mitigated. The Partnership’s top five customers or counterparties accounted for 26% of its total accounts receivable at December 31, 2022, compared to 38% as of December 31, 2021. Fair Value. The carrying amount of cash and cash equivalents, restricted cash, accounts receivable and trade accounts payable reported on the consolidated balance sheet approximates fair value due to their short-term maturities. A summary of the estimated fair value of the Partnership’s debt financial instruments follows. December 31, 2022 December 31, 2021 Carrying Value (1) Estimated Carrying Value (1) Estimated (in thousands) 2025 Senior Notes 259,463 221,733 259,463 234,814 2026 Secured Notes 785,000 750,983 700,000 718,083 (1) Excludes applicable unamortized debt issuance costs and debt discounts. The carrying value on the balance sheets of the ABL Facility and Permian Transmission Term Loan represent their fair value due to its floating interest rate. The fair value for the 2026 Secured Notes and 2025 Senior Notes is based on an average of nonbinding broker quotes as of December 31, 2022 and 2021. The use of different market assumptions or valuation methodologies may have a material effect on the estimated fair value of the Senior Notes. Deferred earn-out. As a result of the acquisition of Sterling DJ, the Partnership assumed a deferred earn-out liability, which is remeasured each reporting period. As of December 31, 2022, the estimated fair value of the deferred earn-out liability was $5.2 million and was estimated using a discounted cash flow technique based on estimated future fresh water deliveries and appropriate discount rates. Given the unobservable nature of the inputs, the fair value measurement of the deferred earn-out is deemed to use Level 3 inputs. The deferred earn-out sits within Centennial Water Pipelines LLC, one of the Partnership’s unrestricted subsidiaries. Interest Rate Swaps. In connection with the Permian Transmission Credit Facility, the Partnership entered into amortizing interest rate swap agreements for a notional amount of $139.8 million. These interest rate swaps manage exposure to variability in expected cash flows attributable to interest rate risk. Interest rate swaps convert a portion of the Partnership’s variable rate debt to fixed rate debt. The Partnership chooses counterparties for its derivative instruments that it believes are creditworthy at the time the transactions are entered into, and the Partnership actively monitors the creditworthiness where applicable. However, there can be no assurance that a counterparty will be able to meet its obligations to the Partnership. The Partnership presents its derivative positions on a gross basis and does not net the asset and liability positions. As of December 31, 2022, the Partnership’s interest rate swap agreements had a fair value of $15.2 million and are recorded within other noncurrent assets, other current liabilities and other noncurrent liabilities within the consolidated balance sheets.

PARTNERS' CAPITAL AND MEZZANINE

PARTNERS' CAPITAL AND MEZZANINE CAPITAL	12 Months Ended
	Dec. 31, 2022
Equity [Abstract]
PARTNERS' CAPITAL AND MEZZANINE CAPITAL	12. PARTNERS' CAPITAL AND MEZZANINE CAPITAL Common Units. An update on the number of common units is as follows for the period from December 31, 2020 to December 31, 2022. Common Units December 31, 2020 6,110,092 2021 Preferred Exchange Offer, net of units withheld for taxes 538,715 Common units issued for SMLP LTIP, net 106,580 ECP Warrant Exercise 414,447 December 31, 2021 7,169,834 2022 Preferred Exchange Offer, net of units withheld for taxes 2,853,875 Common units issued for SMLP LTIP, net 159,054 December 31, 2022 10,182,763 Series A Preferred Units. In November 2017, the Partnership issued 300,000 Series A Fixed-to-Floating Rate Cumulative Redeemable Perpetual Preferred Units (the “Series A Preferred Units”) representing limited partner interests in the Partnership at a price to the public of $1,000 per unit. The Series A Preferred Units rank senior to (i) common units representing limited partner interests in the Partnership and (ii) each other class or series of limited partner interests or other equity securities in the Partnership that may be established in the future that expressly ranks junior to the Series A Preferred Units as to the payment of distributions and amounts payable upon a liquidation event. The Series A Preferred Units rank equal in all respects with each class or series of limited partner interests or other equity securities in the Partnership that may be established in the future that is not expressly made senior or subordinated to the Series A Preferred Units as to the payment of distributions and amounts payable on a liquidation event. The Series A Preferred Units rank junior to (i) all of the Partnership’s existing and future indebtedness and other liabilities with respect to assets available to satisfy claims against the Partnership and (ii) each other class or series of limited partner interests or other equity securities in the Partnership established in the future that is expressly made senior to the Series A Preferred Units as to the payment of distributions and amounts payable upon a liquidation event. Income is allocated to the Series A Preferred Units in an amount equal to the earned distributions (whether these distributions are declared by the General Partner to be paid or not) for the respective reporting period. Distributions on the Series A Preferred Units are cumulative and compounding and are payable semi-annually in arrears on the 15th day of each June and December through and including December 15, 2022, and, thereafter, quarterly in arrears on the 15th day of March, June, September and December of each year (each, a “Distribution Payment Date”) to holders of record as of the close of business on the first business day of the month of the applicable Distribution Payment Date, in each case, when, as, and if declared by the General Partner out of legally available funds for such purpose. The initial distribution rate for the Series A Preferred Units is 9.50% per annum of the $1,000 liquidation preference per Series A Preferred Unit. On and after December 15, 2022, distributions on the Series A Preferred Units will accumulate for each distribution period at a percentage of the liquidation preference equal to the three-month LIBOR plus a spread of 7.43%. The floating rate established on December 15, 2022 for the period ending March 31, 2023 was 12.2%. The Partnership suspended its distributions to be paid to holders of its Series A Preferred Units, commencing with respect to the quarter ending March 31, 2020. As of December 31, 2022, the amount of accrued and unpaid distributions on the Series A Preferred Units was $21.5 million. A rollforward of the number of outstanding Series A Preferred Units follows for the period from December 31, 2020 to December 31, 2022. Series A December 31, 2020 162,109 2021 Preferred Exchange Offer (18,662) December 31, 2021 143,447 2022 Preferred Exchange Offer (77,939) December 31, 2022 65,508 2021 Preferred Exchange Offers . In April 2021, the Partnership completed an offer to exchange its Series A Preferred Units for newly issued common units (the “2021 Preferred Exchange Offer”), whereby it issued 538,715 SMLP common units, net of units withheld for withholding taxes, in exchange for 18,662 Series A Preferred Units. Upon the settlement of the 2021 Preferred Exchange Offer, the Partnership eliminated $20.7 million of the Series A Preferred Unit liquidation preference amount, inclusive of accrued distributions due as of the settlement date. 2022 Preferred Exchange Offer . In January 2022, the Partnership completed an offer to exchange its Series A Preferred Units for newly issued common units (the “2022 Preferred Exchange Offer”), whereby it issued 2,853,875 SMLP common units, net of units withheld for withholding taxes, in exchange for 77,939 Series A Preferred Units. Upon the settlement of the 2022 Preferred Exchange Offer, the Partnership eliminated $92.6 million of the Series A Preferred Unit liquidation preference amount, inclusive of accrued distributions due as of the settlement date. Subsidiary Series A Preferred Units. The Partnership has Subsidiary Series A Preferred Units that ranks senior to each other class or series of limited partner interests or other equity securities in Permian Holdco that may be established in the future that expressly ranks junior to the Subsidiary Series A Preferred Units as to the payment of distributions and amounts payable upon a liquidation event. The Subsidiary Series A Preferred Units rank equal in all respects with each class or series of limited partner interests or other equity securities in Permian Holdco that may be established in the future that is not expressly made senior or subordinated to the Subsidiary Series A Preferred Units as to the payment of distributions and amounts payable on a liquidation event. The Subsidiary Series A Preferred Units rank junior to (i) all of Permian Holdco’s or a subsidiary of Permian Holdco’s future indebtedness and other liabilities with respect to assets available to satisfy claims against Permian Holdco and (ii) each other class or series of limited partner interests or other equity securities in Permian Holdco established in the future that is expressly made senior to the Subsidiary Series A Preferred Units as to the payment of distributions and amounts payable upon a liquidation event. Income is allocated to the Subsidiary Series A Preferred Units in an amount equal to the earned distributions for the respective reporting period. Distributions on the Subsidiary Series A Preferred Units are cumulative and compounding and are payable 21 days following the quarterly period ended March, June, September and December of each year (each, a “Series A Distribution Payment Date”) to holders of record as of the close of business on the first business day of the month of the applicable Series A Distribution Payment Date, in each case, when, as, and if declared by Permian Holdco out of legally available funds for such purpose. The distribution rate for the Subsidiary Series A Preferred Units is 7.00% per annum of the $1,000 liquidation preference per Subsidiary Series A Preferred Unit. A pro-rated initial distribution on the Subsidiary Series A Preferred Units was Paid-in-kind (“PIK”) on January 21, 2020 in an amount equal to 7.00% per Subsidiary Series A Preferred Unit plus 1.00% per annum of the undrawn commitment units. These Subsidiary Series A Preferred Units are considered redeemable securities under GAAP due to the existence of certain redemption provisions that are outside of the Partnership’s control. Therefore, the securities are classified as temporary equity in the mezzanine section of the consolidated balance sheets. The Partnership records its Subsidiary Series A Preferred Units at fair value upon issuance, net of issuance costs, and subsequently records an effective interest method accretion amount each reporting period to accrete the carrying value to a most probable redemption value that is based on a predetermined internal rate of return measure. The Partnership also elected to make PIK distributions to holders of the Subsidiary Series A Preferred Units during portions of the year ended December 31, 2022 and for all of the fiscal year ended December 31, 2021, which increase the liquidation preference on each Subsidiary Series A Preferred Unit. Ultimately, Net Income (Loss) Attributable to common limited partners includes adjustments for PIK distributions and redemption accretion. During the years ended December 31, 2022 and 2021, the Partnership issued 1,600 and 6,131 Subsidiary Series A Preferred Units, respectively, through PIK transactions. As of December 31, 2022 and 2021, the Partnership had 93,039 and 91,439 Subsidiary Series A Preferred Units outstanding, respectively. If the Subsidiary Series A Preferred Units were redeemed on December 31, 2022, the redemption amount would be $119.9 million, when considering the applicable multiple of invested capital metric and make-whole amount provisions contained in the Subsidiary Series A Preferred Unit agreement. The following table shows the change in the Partnership’s Subsidiary Series A Preferred Unit balance from January 1, 2021 through December 31, 2022, net of $2.2 million and $3.9 million of unamortized issuance costs at December 31, 2022 and December 31, 2021: (in thousands) Balance at January 1, 2021 $ 89,658 PIK distributions 6,131 Redemption accretion 10,536 Balance at December 31, 2021 $ 106,325 PIK distributions 1,600 Redemption accretion 15,544 Cash distribution (includes $1.6 million distributions payable as of December 31, 2022) $ (4,885) Balance at December 31, 2022 $ 118,584 Warrants. On May 28, 2020, the Partnership issued (i) a warrant to purchase up to 537,307 SMLP common units to ECP NewCo (the “ECP NewCo Warrant”) and (ii) a warrant to purchase up to 129,360 SMLP common units to ECP Holdings (the “ECP Holdings Warrant” and together with the ECP NewCo Warrant, the “ECP Warrants”). The exercise price under the ECP Warrants was $15.35 per SMLP common unit. At issuance the ECP Warrants were valued at $2.3 million using a Black-Scholes model and accounted for as a liability instrument. On August 5, 2021, the ECP Entities cashlessly exercised all of the ECP Warrants for an aggregate of 414,447 SMLP common units, net of the exercise price, as calculated pursuant to Section 3(c) of the ECP Warrants (the "ECP Warrant Exercise"). For the year ended December 31, 2021, the Partnership recognized a $13.6 million loss related to the ECP Warrants. Cash Distribution Policy. The Partnership suspended its cash distributions to holders of its common units, commencing with respect to the quarter ending March 31, 2020. Upon the resumption of distributions, the Partnership Agreement requires that it distribute all available cash, subject to reserves established by its General Partner, within 45 days after the end of each quarter to unitholders of record on the applicable record date. The amount of distributions paid under this policy is subject to fluctuations based on the amount of cash the Partnership generates from its business and the decision to make any distribution is determined by the General Partner, taking into consideration the terms of the Partnership Agreement.

EARNINGS PER UNIT

EARNINGS PER UNIT	12 Months Ended
	Dec. 31, 2022
Earnings Per Share [Abstract]
EARNINGS PER UNIT	13. EARNINGS PER UNIT The following table details the components of EPU. Year ended December 31, 2022 2021 (In thousands, except per-unit amounts) Numerator for basic and diluted EPU: Allocation of net income (loss) among limited partner interests: Net loss $ (123,461) $ (19,949) Less: Net income attributable to Subsidiary Series A Preferred Units (17,144) (16,667) Net loss attributable Summit Midstream Partners, LP (140,605) (36,616) Less: Net income attributable to Series A Preferred Unit (8,048) (15,998) Add: Deemed capital contribution 20,974 8,326 Net loss attributable to common limited partners $ (127,679) $ (44,288) Denominator for basic and diluted EPU: Weighted-average common units outstanding – basic 10,048 6,741 Effect of nonvested phantom units — — Weighted-average common units outstanding – diluted 10,048 6,741 Net Loss per limited partner unit: Common unit – basic $ (12.71) $ (6.57) Common unit – diluted $ (12.71) $ (6.57) Nonvested anti-dilutive phantom units excluded from the calculation of diluted EPU 177 203

SUPPLEMENTAL CASH FLOW INFORMAT

SUPPLEMENTAL CASH FLOW INFORMATION	12 Months Ended
	Dec. 31, 2022
Supplemental Cash Flow Elements [Abstract]
SUPPLEMENTAL CASH FLOW INFORMATION	14. SUPPLEMENTAL CASH FLOW INFORMATION Year ended December 31, 2022 2021 (In thousands) Supplemental cash flow information: Cash interest paid $ 89,472 $ 57,655 Cash paid for taxes 149 191 Noncash investing and financing activities: Capital expenditures in trade accounts payable (period-end accruals) $ 6,724 $ 5,692 Accretion of Subsidiary Series A Preferred Units 15,544 10,536 Exercise of ECP Warrants — 15,542 2022 Preferred Exchange Offer 92,587 — 2021 Preferred Exchange Offer — 20,654

UNIT-BASED AND NONCASH COMPENSA

UNIT-BASED AND NONCASH COMPENSATION	12 Months Ended
	Dec. 31, 2022
Share-Based Payment Arrangement [Abstract]
UNIT-BASED AND NONCASH COMPENSATION	15. UNIT-BASED AND NONCASH COMPENSATION SMLP Long-Term Incentive Plan. The Partnership’s Long-Term Incentive Plan (“SMLP LTIP”) provides for equity awards to eligible officers, employees, consultants and directors of the Partnership, thereby linking the recipients' compensation directly to SMLP’s performance. The SMLP LTIP provides for the granting, from time to time, of unit-based awards, including common units, restricted units, phantom units, unit options, unit appreciation rights, distribution equivalent rights, profits interest units and other unit-based awards. Grants are made at the discretion of the Board of Directors or Compensation Committee. Initially, a total of 1.0 million common units was reserved for issuance pursuant to and in accordance with the SMLP LTIP. On June 24, 2022 unitholders of the Partnership approved the Summit Midstream Partners, LP 2022 Long-Term Incentive Plan, which increased the number of common units available for issuance to the Partnership’s employees, consultants and directors. As of December 31, 2022, approximately 0.9 million common units remained available for future issuance under the SMLP LTIP, which includes the impact of 0.6 million granted but unvested phantom units. Significant items for the year ended December 31, 2022: • For the year ended December 31, 2022, the Partnership granted 170,986 phantom units and associated distribution equivalent rights to employees. These awards granted during the year ended December 31, 2022 had fair values of between $13.58 and $20.50 per common unit and vest ratably over periods ranging from a two-year period and three-year period. • For the year ended December 31, 2022, certain employees of the Partnerships exchanged previously granted cash retention awards for 299,981 phantom units. The fair value of the cash retention awards exchanged was equal to the fair value of the phantom units received and the phantom awards vest over same terms of the cash retention awards. • For the year ended December 31, 2022, the Partnership issued 38,664 common units to the Partnership’s six independent directors in connection with their annual compensation plan. These awards had a grant date fair value of $14.21 per common unit and vested immediately. The following table presents phantom unit activity for the periods presented: Units Weighted-average grant date fair value Nonvested phantom units, December 31, 2020 291,691 $ 26.57 Phantom units granted 199,241 22.33 Phantom units vested (143,768) 30.66 Phantom units forfeited (13,385) 38.85 Nonvested phantom units, December 31, 2021 333,779 21.78 Phantom units granted 509,631 17.70 Phantom units vested (229,551) 23.61 Phantom units forfeited (8,717) 22.53 Nonvested phantom units, December 31, 2022 605,142 $ 17.62 A phantom unit is a notional unit that entitles the grantee to receive a common unit upon the vesting of the phantom unit or on a deferred basis upon specified future dates or events or, in the discretion of the administrator, cash equal to the fair market value of a common unit. Distribution equivalent rights for each phantom unit provide for a lump sum cash amount equal to the accrued distributions from the grant date to be paid in cash upon the vesting date. P hantom units granted to date generally vest ratably over a three-year period. Grant date fair value is determined based on the closing price of SMLP’s common units on the date of grant multiplied by the number of phantom units awarded to the grantee. Forfeitures are recorded as incurred. Holders of all phantom units granted to date are entitled to receive distribution equivalent rights for each phantom unit, providing for a lump sum cash amount equal to the accrued distributions from the grant date of the phantom units to be paid in cash upon the vesting date. Upon vesting, phantom unit awards may be settled, at the Partnership’s discretion, in cash and/or common units, but the current intention is to settle all phantom unit awards with common units. The intrinsic value of phantom units that vested during the years ended December 31, follows. Year ended December 31, 2022 2021 (In thousands) Intrinsic value of vested LTIP awards $ 5,420 $ 4,407 As of December 31, 2022, the unrecognized unit-based compensation related to the SMLP LTIP was $6.3 million. Incremental unit-based compensation will be recorded over the remaining weighted-average vesting period of approximately 1.62 years. Unit-based compensation recognized in general and administrative expense related to awards under the SMLP LTIP follows. Year ended December 31, 2022 2021 (In thousands) SMLP LTIP unit-based compensation $ 3,778 $ 4,744

LEASES

LEASES	12 Months Ended
	Dec. 31, 2022
Leases [Abstract]
LEASES	16. LEASES Leases. The Partnership leases certain office space and equipment under operating leases. The Partnership leases office space for terms of between 3 and 10 years. Office space leases limit exposure to risks related to ownership, such as fluctuations in real estate prices. The Partnership leases equipment primarily to support its operations in response to the needs of its gathering systems for terms of between 3 and 4 years. The Partnership also leases vehicles under finance leases to support its operations in response to the needs of its gathering systems for a term of 3 years. Some of the Partnership’s leases are subject to annual escalations relating to the Consumer Price Index (“CPI”). While lease liabilities are not remeasured as a result of changes to the CPI, changes to the CPI are treated as variable lease payments and recognized in the period in which the obligation for those payments was incurred. Significant assumptions or judgments include the determination of whether a contract contains a lease and the discount rate used in the lease liabilities. The rate implicit in the lease contracts are not readily determinable. In determining the discount rate used for lease liabilities, the Partnership analyzed certain factors in its incremental borrowing rate, including collateral assumptions and the term used. The Partnership’s incremental borrowing rate was 6.43% at December 31, 2022, which reflects the rate at which the Partnership could borrow a similar amount, for a similar term and with similar collateral as in the lease contracts at the commencement date. ROU assets (included in the other noncurrent assets Other current liabilities Other noncurrent liabilities December 31, 2022 December 31, 2021 (In thousands) ROU assets Operating $ 11,633 $ 2,515 Finance 1,389 792 $ 13,022 $ 3,307 Lease liabilities, current Operating $ 2,570 $ 1,213 Finance 435 167 $ 3,005 $ 1,380 Lease liabilities, noncurrent Operating $ 9,672 $ 2,272 Finance 679 122 $ 10,351 $ 2,394 Lease cost and Other information follow: Year ended December 31, 2022 2021 (In thousands) Lease cost Finance lease cost: Amortization of ROU assets (included in depreciation and amortization) $ 673 $ 1,026 Interest on lease liabilities (included in interest expense) 18 20 Operating lease cost (included in general and administrative expense) 1,815 1,722 $ 2,506 $ 2,768 Year ended December 31, 2022 2021 (In thousands) Other information Cash paid for amounts included in the measurement of lease liabilities Operating cash outflows from operating leases $ 1,732 $ 1,407 Operating cash outflows from finance leases 18 20 Financing cash outflows from finance leases 330 634 ROU assets obtained in exchange for new operating lease liabilities 9,865 — ROU assets obtained in exchange for new finance lease liabilities 1,298 94 Weighted-average remaining lease term (years) - operating leases 4.7 5.1 Weighted-average remaining lease term (years) - finance leases 2.4 1.1 Weighted-average discount rate - operating leases 6 % 5 % Weighted-average discount rate - finance leases 3 % 4 % The Partnership recognizes total lease expense incurred or allocated to us in general and administrative expenses. Lease expense related to operating leases, including lease expense incurred on the Partnership’s behalf and allocated to us, was as follows: Year ended December 31, 2022 2021 (In thousands) Lease expense $ 3,162 $ 2,479 Future minimum lease payments due under noncancelable leases at December 31, 2022, were as follows: December 31, 2022 (In thousands) Operating Finance 2023 $ 4,026 $ 538 2024 3,650 489 2025 3,486 276 2026 2,646 7 2027 2,280 — 2028 61 — Thereafter 357 — Total future minimum lease payments $ 16,506 $ 1,310

SEGMENT INFORMATION

SEGMENT INFORMATION	12 Months Ended
	Dec. 31, 2022
Segment Reporting [Abstract]
SEGMENT INFORMATION	17. SEGMENT INFORMATION As of December 31, 2022, the Partnership’s current reportable segments are: • Rockies – Includes the Partnership’s wholly owned midstream assets located in the Williston Basin and the DJ Basin. • Permian – Includes the Partnership’s equity method investment in Double E. • Northeast – Includes the Partnership’s wholly owned midstream assets located in the Utica and Marcellus shale plays and the equity method investment in Ohio Gathering that is focused on the Utica Shale. • Piceance – Includes the Partnership’s wholly owned midstream assets located in the Piceance Basin. • Barnett – Includes the Partnership’s wholly owned midstream assets located in the Barnett Shale. Corporate and Other represents those results that: (i) are not specifically attributable to a reportable segment; (ii) are not individually reportable; or (iii) have not been allocated to a reportable segments for the purpose of evaluating their performance, including certain general and administrative expense items, certain natural gas and crude oil marketing services and transaction costs. Assets by reportable segment follow. December 31, 2022 2021 (in thousands) Assets: Northeast $ 591,091 $ 623,224 Rockies 886,629 592,148 Permian 298,906 458,988 Piceance 475,719 524,218 Barnett 295,473 315,055 Total reportable segment assets 2,547,818 2,513,633 Corporate and Other 12,146 8,829 Total assets $ 2,559,964 $ 2,522,462 Revenues by reportable segment follow. Year ended December 31, 2022 2021 (In thousands) Revenues: Northeast $ 54,392 $ 62,567 Rockies 143,603 145,087 Permian 25,151 40,848 Piceance 93,349 105,485 Barnett 52,096 46,591 Total reportable segments revenue 368,591 400,578 Corporate and Other 1,003 40 Total revenues $ 369,594 $ 400,618 Counterparties accounting for a significant portion of total revenues were as follows: Year ended December 31, 2022 2021 Percentage of total revenues (1) : Counterparty A - Piceance 13 % 12 % ________________________________________________________ Depreciation and amortization, including the amortization expense associated with the Partnership’s favorable and unfavorable gas gathering contracts as reported in other revenues, by reportable segment follow. Year ended December 31, 2022 2021 (In thousands) Depreciation and amortization: Northeast $ 17,501 $ 17,054 Rockies 30,532 29,513 Permian 2,736 5,858 Piceance 51,352 48,773 Barnett (1) 16,116 16,133 Total reportable segment depreciation and amortization 118,237 117,331 Corporate and Other 1,756 2,664 Total depreciation and amortization $ 119,993 $ 119,995 ______________________________________ (1) Includes the amortization expense associated with the Partnership’s favorable and unfavorable gas gathering contracts as reported in Other revenues. Cash paid for capital expenditures by reportable segment follow. Year ended December 31, 2022 2021 (In thousands) Cash paid for capital expenditures: Northeast $ 8,743 $ 11,237 Rockies 11,903 9,875 Permian 1,407 2,042 Piceance 6,116 579 Barnett 366 766 Total reportable segment capital expenditures 28,535 24,499 Corporate and Other 1,937 531 Total cash paid for capital expenditures $ 30,472 $ 25,030 The Partnership assesses the performance of its reportable segments based on segment adjusted EBITDA. The Partnership defines segment adjusted EBITDA as total revenues less total costs and expenses; plus (i) other income excluding interest income, (ii) proportional adjusted EBITDA for equity method investees, (iii) depreciation and amortization, (iv) adjustments related to MVC shortfall payments, (v) adjustments related to capital reimbursement activity, (vi) unit-based and noncash compensation, (vii) impairments (vii) other noncash expenses or losses, less other noncash income or gains and (ix) restructuring expenses. Proportional adjusted EBITDA for the Partnership’s equity method investees is defined as the product of (i) total revenues less total expenses, excluding impairments and other noncash income or expense items, and amortization for deferred contract costs; and (ii) ownership interest in Ohio Gathering during the respective period. For the purpose of evaluating segment performance, the Partnership excludes the effect of Corporate and Other revenues and expenses, such as certain general and administrative expenses (including compensation-related expenses and professional services fees), certain natural gas and crude oil marketing services, transaction costs, interest expense and income tax expense or benefit from segment adjusted EBITDA. Segment adjusted EBITDA by reportable segment follows. Year ended December 31, 2022 2021 (In thousands) Reportable segment adjusted EBITDA Northeast $ 77,046 $ 83,287 Rockies 57,810 64,517 Permian 18,051 6,614 Piceance 60,055 76,131 Barnett 31,624 36,729 Total of reportable segments' measures of profit $ 244,586 $ 267,278 A reconciliation of income or loss before income taxes and income or loss from equity method investees to total of reportable segments' measures of profit or loss follows. Year ended December 31, 2022 2021 (In thousands) Reconciliation of income (loss) before income taxes and income (loss) from equity method investees to total of reportable segments' measures of profit: Loss before income taxes and income from equity method investees $ (141,277) $ (28,156) Add: Corporate and Other expense 29,118 68,783 Interest expense 102,459 66,156 Gain on early extinguishment of debt — 3,523 Depreciation and amortization (1) 119,993 119,995 Proportional adjusted EBITDA for equity method investees 45,419 29,022 Adjustments related to capital reimbursement activity (6,041) (6,571) Unit-based and noncash compensation 3,778 4,744 Gain on asset sales, net (507) (369) Long-lived asset impairment 91,644 10,151 Total of reportable segments' measures of profit $ 244,586 $ 267,278 ______________________________________ (1) Includes the amortization expense associated with the Partnership’s favorable gas gathering contracts as reported in other revenues. For the years ended December 31, 2022 and 2021, adjustments related to MVC shortfall payments recognize the earnings from MVC shortfall payments ratably over the term of the associated MVC. Contributions in aid of construction are recognized over the remaining term of the respective contract. The Partnership includes adjustments related to capital reimbursement activity in its calculation of segment adjusted EBITDA to account for revenue recognized from contributions in aid of construction.

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Presentation and Consolidation	The Partnership prepares its consolidated financial statements in accordance with GAAP as established by the FASB. The Partnership makes estimates and assumptions that affect the reported amounts of assets and liabilities at the balance sheet dates, including fair value measurements, the reported amounts of revenues and expenses and the disclosure of commitments and contingencies. Although management believes these estimates are reasonable, actual results could differ from its estimates.The consolidated financial statements include the assets, liabilities and results of operations of SMLP and its subsidiaries. All intercompany transactions among the consolidated entities have been eliminated in consolidation. Comprehensive income or loss is the same as net income or loss for all periods presented.
Cash, Cash Equivalents and Restricted Cash	The Partnership considers all highly liquid investments with an original maturity of three months or less to be cash equivalents. Cash that is held by a major bank and has restrictions on its availability to the Partnership is classified as restricted cash. The restricted cash balance of $1.7 million and $12.2 million at December 31, 2022 and 2021, respectively, is related to proceeds which are available to finance Permian Transmission’s debt service or other general corporate purposes of Permian Transmission. See Note 9 - Debt for additional information.
Accounts Receivable	Accounts receivable relate to gathering and other services provided to the Partnership’s customers and other counterparties. The Partnership evaluates the collectability of accounts receivable and the need for an allowance for doubtful accounts based on customer-specific facts and circumstances. To the extent the collectability of a specific customer or counterparty receivable is doubtful, the Partnership recognizes an allowance for doubtful accounts. Uncollectible receivables are written off when a settlement is reached for an amount that is less than the outstanding historical balance or a receivable amount is deemed otherwise unrealizable.
Property, Plant and Equipment	The Partnership records property, plant and equipment at historical cost of construction or fair value of the assets at acquisition. The Partnership capitalizes expenditures that extend the useful life of an asset or enhance its productivity or efficiency from its original design over the expected remaining period of use. For maintenance and repairs that do not add capacity or extend the useful life of an asset, the Partnership recognizes expenditures as an expense as incurred. The Partnership capitalizes project costs incurred during construction, including interest on funds borrowed to finance the construction of facilities and pipelines, as construction in progress. Accrued capital expenditures are reflected in trade accounts payable. The Partnership records depreciation on a straight-line basis over an asset’s estimated useful life and bases its estimates for useful life on various factors including age (in the case of acquired assets), manufacturing specifications, technological advances and historical data concerning useful lives of similar assets. Estimates of useful lives follow. Useful lives Gathering and processing systems and related equipment 12-30 Other 4-15 Construction in progress is depreciated consistent with its applicable asset class once it is placed in service. Land and line fill are not depreciated. The Partnership bases an asset’s carrying value on estimates, assumptions and judgments for useful life and salvage value. Upon sale, retirement or other disposal, the Partnership removes the carrying value of an asset and its accumulated depreciation from its balance sheet and recognizes the related gain or loss, if any.
Asset Retirement Obligations	The Partnership records a liability for asset retirement obligations only if and when a future asset retirement obligation with a determinable life is identified. For identified asset retirement obligations, the Partnership evaluates whether the expected retirement date and related costs of retirement can be estimated. The Partnership has concluded that its gathering and processing assets have an indeterminate life because they are owned and will operate for an indeterminate period when properly maintained. Because the Partnership does not have sufficient information to reasonably estimate the amount or timing of such obligations and does not have any current plan to discontinue use of any significant assets, the Partnership did not provide for any asset retirement obligations as of December 31, 2022 or 2021.
Amortizing Intangibles	The Partnership has certain acquired gas gathering contracts that had above-market pricing structures at the acquisition date and the Partnership amortizes these favorable contracts using a straight-line method over the contract’s estimated useful life. The Partnership defines useful life as the period over which the contract is expected to contribute to the Partnership’s future cash flows. These favorable contracts have original terms ranging from 10 years to 20 years and the Partnership recognizes the amortization expense associated with these contracts in Other revenues. The Partnership amortizes all other gas gathering contracts, or contract intangibles, over the period of economic benefit based upon expected revenues over the life of the contract. The useful life of these contracts ranges from 3 years to 25 years. The Partnership recognizes the amortization expense associated with these contracts in Depreciation and amortization expense. The Partnership also has rights-of-way associated with municipal easements and easements granted within existing rights-of-way. The Partnership amortizes these intangible assets over the shorter of the contractual term of the rights-of-way or the estimated useful life of the gathering system. The contractual terms of the rights-of-way range from 20 years to 30 years and the Partnership recognizes the amortization expense associated with these rights-of-way assets in Depreciation and amortization expense.
Equity Method Investments	The Partnership accounts for investments in which it exercises significant influence using the equity method so long as it (i) does not control the investee and (ii) is not the primary beneficiary. The Partnership reflects these investments in its consolidated balance sheets under the caption titled “investment in equity method investees.”The Partnership recognizes an other-than-temporary impairment for losses in the value of equity method investees when evidence indicates that the carrying amount is no longer supportable. Evidence of a loss in value might include, but is not limited to, absence of an ability to recover the carrying amount of the investment or an inability of the equity method investee to sustain an earnings capacity that would justify the carrying amount of the investment. A current fair value of an investment that is less than its carrying amount may indicate a loss in value of the investment. The Partnership evaluates its equity method investments for impairment whenever a triggering event exists that would indicate a need to assess the investment for potential impairment.
Impairment of Long-Lived Assets	The Partnership tests assets for impairment when events or circumstances indicate the carrying value of a long-lived asset may not be recoverable. The carrying value of a long-lived asset is not recoverable if it exceeds the sum of the undiscounted cash flows expected to result from its use and eventual disposition. If the Partnership concludes that an asset’s carrying value will not be recovered through future cash flows, the Partnership recognizes an impairment loss on the long-lived asset equal to the amount by which the carrying value exceeds its fair value. The Partnership determines fair value using a combination of market-based and income-based approaches.
Environmental Matters	The Partnership is subject to various federal, state and local laws and regulations relating to the protection of the environment. Liabilities for loss contingencies, including environmental remediation costs, arising from claims, assessments, litigation, fines and penalties and other sources are charged to expense when it is probable that a liability has been incurred and the amount of the assessment and/or remediation can be reasonably estimated. The Partnership accrues for losses associated with environmental remediation obligations when such losses are probable and reasonably estimable. Such accruals are adjusted as further information develops or circumstances change. Recoveries of environmental remediation costs from other parties or insurers are recorded as assets when their realization is assured beyond a reasonable doubt.
Commitments and Contingencies	When required, the Partnership records accruals for loss contingencies in accordance with FASB ASC 450, Contingencies . Such determinations are subject to interpretations of current facts and circumstances, forecasts of future events and estimates of the financial impacts of such events.
Noncontrolling Interest and Mezzanine Capital	A noncontrolling interest is reported as a component of equity unless the noncontrolling interest is considered redeemable, in which case the noncontrolling interest is recorded between liabilities and equity (mezzanine or temporary equity) in the Partnership’s consolidated balance sheet.
Revenue Recognition	The Partnership provides gathering and/or processing services principally under contracts that contain one or more of the following arrangements described below: • Fee-based arrangements. Under fee-based arrangements, the Partnership receives a fee or fees for one or more of the following services (i) natural gas gathering, treating, transporting, compressing and/or processing and (ii) crude oil and/or produced water gathering and (iii) fresh water delivery services. • Percent-of-proceeds arrangements. Under percent-of-proceeds arrangements, the Partnership generally purchases natural gas from producers at the wellhead, or other receipt points, gathers the wellhead natural gas through its gathering system, treats and compresses the natural gas, processes the natural gas and/or sells the natural gas to a third party for processing. The Partnership then remits to its producers an agreed-upon percentage of the actual proceeds received from sales of the residue natural gas and NGLs. Certain of these arrangements may also result in returning all or a portion of the residue natural gas and/or the NGLs to the producer, in lieu of returning sales proceeds. The margins earned are directly related to the volume of natural gas that flows through the system and the price at which the Partnership is able to sell the residue natural gas and NGLs. The majority of the Partnership’s contracts have a single performance obligation which is either to provide gathering services (an integrated service) or sell natural gas, NGLs and condensate, which are both satisfied when the related natural gas, crude oil and produced water are received and transferred to an agreed upon delivery point. The Partnership also has certain contracts with multiple performance obligations. They include an option for the customer to acquire additional services such as contracts containing MVCs. These performance obligations would also be satisfied when the related natural gas, crude oil and produced water are received and transferred to an agreed upon delivery point. In these instances, the Partnership allocates the contract’s transaction price to each performance obligation using its best estimate of the standalone selling price of each service in the contract. Performance obligations for gathering services are generally satisfied over time. The Partnership utilizes either an output method (i.e., measure of progress) for guaranteed, stand-ready service contracts or an asset/system delivery time estimate for non-guaranteed, as-available service contracts. Performance obligations for the sale of natural gas, NGLs and condensate are satisfied at a point in time. There are no significant judgments for these transactions because the customer obtains control based on an agreed upon delivery point. Services are typically billed on a monthly basis and the Partnership does not offer extended payment terms. The Partnership does not have contracts with financing components. For the contracts described above, the Partnership reflects its revenues in the financial statement captions described below. Financial statement caption: Revenue description: Revenues: Gathering services and related fees • Revenue earned from fee-based gathering, compression, treating and processing services; Natural gas, NGLs and condensate sales • Revenue from the sale of physical natural gas purchased from customers percent-of- proceeds arrangements (Costs are presented within cost of natural gas and NGLs); • Revenue from sale of condensate and NGLs retained from gathering services (Costs are presented within operation and maintenance expense); Other revenues • Reimbursements to the Partnership for costs incurred by the Partnership on customer’s behalf (Recorded on a gross basis with corresponding costs included in operations and maintenance expense); • Revenue for freshwater deliveries; and • Revenue for management fees related to Double E. Certain of the Partnership’s gathering and/or processing agreements provide for monthly or annual MVCs. Under these MVCs, customers agree to ship and/or process a minimum volume of production on its gathering systems or to pay a minimum monetary amount over certain periods during the term of the MVC. A customer must make a shortfall payment to the Partnership at the end of the contracted measurement period if its actual throughput volumes are less than its contractual MVC for that period. Certain customers are entitled to utilize shortfall payments to offset gathering fees in one or more subsequent contracted measurement periods to the extent that such customers throughput volumes in a subsequent contracted measurement period exceed its MVC for that contracted measurement period. The Partnership recognizes customer obligations under their MVCs as revenue and contract assets when (i) it considers it remote that the customer will utilize shortfall payments to offset gathering or processing fees in excess of its MVCs in subsequent periods; (ii) the customer incurs a shortfall in a contract with no banking mechanism or claw back provision; (iii) the customer’s banking mechanism has expired; or (iv) it is remote that the customer will use its unexercised right. In making this determination, the Partnership considers both quantitative and qualitative facts and circumstances, including, but not limited to, contract terms, capacity of the associated pipeline or receipt point and/or expectations regarding future investment, drilling and production. The majority of the Partnership’s revenue is derived from long-term, fee-based contracts with its customers, which include original terms of up to 25 years. The Partnership recognizes revenue earned from fee-based gathering, compression, treating and processing services in gathering services and related fees. The Partnership also earns revenue in the Rockies, Permian and Piceance reporting segments from the sale of physical natural gas purchased from its customers under certain percent-of-proceeds arrangements. Under ASC Topic 606, these gathering contracts are presented net within cost of natural gas and NGLs. The Partnership sells natural gas that it retains from certain customers in the Barnett reporting segment to offset the power expenses, included in operations and maintenance expense, of the electric-driven compression on the gathering system. The Partnership also sells condensate and NGLs retained from certain of its gathering services in the Piceance and Rockies reporting segments. Revenues from the sale of natural gas and condensate are recognized in Natural gas, NGLs and condensate sales; the associated expense is included in Operation and maintenance expense. Certain customers reimburse the Partnership for costs incurred on their behalf. The Partnership records costs incurred and reimbursed by its customers on a gross basis, with the revenue component recognized in Other revenues and the associated expense included in operations and maintenance expense. The transaction price in the Partnership’s contracts is primarily based on the volume of natural gas, crude oil or produced water transferred by its gathering systems to the customer’s agreed upon delivery point multiplied by the contractual rate. For contracts that include MVCs, variable consideration up to the MVC will be included in the transaction price. For contracts that do not include MVCs, the Partnership does not estimate variable consideration because the performance obligations are completed and settled on a daily basis. For contracts containing noncash consideration such as fuel received in-kind, the Partnership measures the transaction price at the point of sale when the volume, mix and market price of the commodities are known. The Partnership has contracts with MVCs that are variable and constrained. Contracts with longer than monthly MVCs are reviewed on a quarterly basis and adjustments to those estimates are made during each respective reporting period, if necessary. The transaction price is allocated if the contract contains more than one performance obligation such as contracts that include MVCs. The transaction price allocated is based on the MVC for the applicable measurement period.
Unit-Based Compensation	For awards of unit-based compensation, the Partnership determines a grant date fair value and recognizes the related compensation expense in the statements of operations over the vesting period for each respective award.
Income Taxes	The Partnership is generally not subject to federal and state income taxes, except as noted below. However, its unitholders are individually responsible for paying federal and state income taxes on their share of its taxable income. Net income or loss for GAAP purposes may differ significantly from taxable income reportable to its unitholders as a result of differences between the tax basis and the GAAP basis of assets and liabilities and the taxable income allocation requirements of the Partnership’s governing documents. The aggregate difference in the basis of the Partnership’s net assets for financial and income tax purposes cannot be readily determined as the Partnership does not have access to the information about each partner’s tax attributes related to the Partnership.In general, legal entities that are chartered, organized or conducting business in the state of Texas are subject to a franchise tax (the “Texas Margin Tax”). The Texas Margin Tax has the characteristics of an income tax because it is determined by applying a tax rate to a tax base that considers both revenues and expenses. The Partnership’s financial statements reflect provisions for these tax obligations.
Interest Rate Swaps	Interest rate swap agreements are reported as either assets or liabilities on the consolidated balance sheet at fair value. Interest rate swap agreements are not designated as cash-flow hedges, and accordingly, the changes in the fair value are recorded in earnings. The Partnership does not use interest rate swap agreements for speculative purposes.
New Accounting Standards Implemented in this Annual Report	New accounting standards not yet implemented in this Annual Report. ASU No. 2020-06 Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815 – 40) (“ASU 2020-06”). ASU 2020-06 simplifies the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts on an entity’s own equity. The ASU is part of the FASB’s simplification initiative, which aims to reduce unnecessary complexity in GAAP. The ASU’s amendments are effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years. The Partnership does not expect the provisions of ASU 2020-06 will have a material impact on its consolidated financial statements and disclosures. ASU No. 2020-04, Reference Rate Reform (Topic 848) - Facilitation of the Effects of Reference Rate Reform on Financial Reporting (“ASU 2020-04”) and ASU No. 2022-06, Reference Rate Reform (Topic 848) - Deferral of the Sunset Date of Topic 848 (“ASU 2022-06”). ASU 2020-04 and ASU 2022-06 provide optional expedients and exceptions for applying GAAP to contracts, hedging relationships and other transactions affected by reference rate reform on financial reporting. The amendments in ASU 2020-04 and ASU 2022-06 are effective as of March 12, 2020 through December 31, 2024. The Partnership does not expect the provisions of ASU 2020-04 and ASU 2022-06 will have a material impact on its consolidated financial statements and disclosures.

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Schedule of Useful lives of Property, Plant and Equipment	Estimates of useful lives follow. Useful lives Gathering and processing systems and related equipment 12-30 Other 4-15

ACQUISTIONS AND DIVESTITURES (T

ACQUISTIONS AND DIVESTITURES (Tables)	12 Months Ended
	Dec. 31, 2022
Business Combination and Asset Acquisition [Abstract]
Schedule of Fair Value of the Assets and Liabilities Acquired	The following table sets forth the preliminary fair value of the assets acquired and liabilities assumed as of the acquisition date. Certain data and assessments necessary to complete the purchase price allocation are still under evaluation, including, but not limited to, the final actualization of accrued liabilities and receivable balances and the valuation of property, plant and equipment and intangible assets. The Partnership will finalize the purchase price allocation during the twelve-month period following the acquisition date, during which time the value of the assets and liabilities may be revised as appropriate. (in thousands) Total consideration paid for Outrigger DJ $ 167,631 Recognized amounts of identifiable assets acquired and liabilities assumed: Cash 1,000 Accounts receivable 7,529 Other current assets 190 Property, plant and equipment, net 144,514 Intangible assets 21,447 Trade accounts payable, accrued expenses and other (7,049) Net assets acquired and liabilities assumed $ 167,631 (in thousands) Total consideration paid for Sterling DJ $ 140,396 Recognized amounts of identifiable assets acquired and liabilities assumed: Cash 500 Accounts receivable 16,224 Other current assets 4,557 Property, plant and equipment, net 108,720 Intangible assets 38,678 Other noncurrent assets 9,865 Trade accounts payable, accrued expenses and other (38,148) Net assets acquired $ 140,396
Schedule of Pro Forma Information	The following table summarizes the unaudited pro forma condensed financial information of SMLP as if the acquisitions of Outrigger DJ and Sterling DJ, along with the dispositions of Bison Midstream and the Lane G&P System, had occurred on January 1, 2021: Year Ended Year Ended Revenues $ 543,024 $ 471,787 Net loss $ (36,945) $ (35,396)

REVENUE (Tables)

REVENUE (Tables)	12 Months Ended
	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
Schedule of Estimated Revenue Expected to be Recognized and MVC Shortfall Payments	The following table presents estimated revenue expected to be recognized over the remaining contract period related to performance obligations that are unsatisfied and are comprised of estimated MVC shortfall payments. The Partnership applies the practical expedient in paragraph 606-10-50-14 of Topic 606 for certain arrangements that are considered optional purchases (i.e., there is no enforceable obligation for the customer to make purchases) and those amounts are therefore excluded from the table. 2023 2024 2025 2026 2027 Thereafter (in thousands) Gathering services and related fees $ 78,245 $ 67,079 $ 46,803 $ 30,527 $ 9,038 $ 6,042
Schedule of Disaggregated Revenue by Geographic Area and Major Products and Services Reportable Segments	In the following table, revenue is disaggregated by geographic area and major products and services. For more detailed information about reportable segments, see Note 17 -Segment Information. Year ended December 31, 2022 Gathering services and related fees Natural gas, NGLs and condensate sales Other revenues Total (in thousands) Reportable Segments: Northeast $ 54,392 $ — $ — $ 54,392 Rockies 67,838 59,208 16,557 143,603 Permian 3,668 17,382 4,101 25,151 Piceance 80,630 7,111 5,608 93,349 Barnett 41,830 2,503 7,763 52,096 Total reportable segments 248,358 86,204 34,029 368,591 Corporate and other — 21 982 1,003 Total $ 248,358 $ 86,225 $ 35,011 $ 369,594 Year ended December 31, 2021 Gathering services and related fees Natural gas, NGLs and condensate sales Other revenues Total (in thousands) Reportable Segments: Northeast $ 62,567 $ — $ — $ 62,567 Rockies 74,823 48,279 21,985 145,087 Permian 8,230 28,727 3,891 40,848 Piceance 95,235 5,464 4,786 105,485 Barnett 40,850 298 5,443 46,591 Total reportable segments 281,705 82,768 36,105 400,578 Corporate and other — — 40 40 Total $ 281,705 $ 82,768 $ 36,145 $ 400,618

PROPERTY, PLANT, AND EQUIPMENT

PROPERTY, PLANT, AND EQUIPMENT (Tables)	12 Months Ended
	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant, and Equipment, Net	Details on the Partnership’s property, plant and equipment follow. December 31, 2022 December 31, 2021 (In thousands) Gathering and processing systems and related equipment $ 2,262,330 $ 2,225,267 Construction in progress 59,036 49,082 Land and line fill 11,756 10,644 Other 62,222 51,863 Total 2,395,344 2,336,856 Less accumulated depreciation (676,590) (610,774) Property, plant and equipment, net $ 1,718,754 $ 1,726,082
Schedule of Depreciation Expense and Capitalized Interest Costs	Depreciation expense and capitalized interest for the Partnership follow. Year ended December 31, 2022 2021 (In thousands) Depreciation expense $ 93,457 $ 90,711 Capitalized interest 838 $ 1,534

INTANGIBLE ASSETS (Tables)

INTANGIBLE ASSETS (Tables)	12 Months Ended
	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets and Liabilities Subject to Amortization	Details regarding the Partnership’s intangible assets follow. December 31, 2022 Gross carrying amount Accumulated amortization Net (In thousands) Favorable gas gathering contracts $ 21,063 $ (14,809) $ 6,254 Contract intangibles 270,412 (228,143) 42,269 Rights-of-way 200,089 (58,330) 141,759 Indefinite-lived intangibles 8,436 — 8,436 Total intangible assets $ 500,000 $ (301,282) $ 198,718 December 31, 2021 Gross carrying amount Accumulated amortization Net (In thousands) Favorable gas gathering contracts $ 24,195 $ (17,002) $ 7,193 Contract intangibles 278,448 (217,245) 61,203 Rights-of-way 159,916 (55,385) 104,531 Total intangible assets $ 462,559 $ (289,632) $ 172,927
Schedule of Recognized Amortization Expense in Other Revenues and Cost and Expenses	The Partnership recognized amortization expense of its favorable gas gathering contracts in Other revenues as follows: Year ended December 31, 2022 2021 (In thousands) Amortization expense – favorable gas gathering contracts $ 938 $ 938 The Partnership recognized amortization expense of its contract and right of way intangibles in costs and expenses as follows: Year ended December 31, 2022 2021 (In thousands) Amortization expense – contract intangibles $ 18,935 $ 22,002 Amortization expense – rights-of-way 6,527 6,344
Schedule of Estimated Aggregate Annual Amortization Expected to be Recognized	The Partnership’s estimated aggregate annual amortization expected to be recognized for each of the five succeeding fiscal years and thereafter, as of December 31, 2022, follows. (In thousands) 2023 $ 27,749 2024 17,563 2025 17,379 2026 14,354 2027 8,365 Thereafter 104,872 $ 190,282

EQUITY METHOD INVESTMENTS (Tabl

EQUITY METHOD INVESTMENTS (Tables)	12 Months Ended
	Dec. 31, 2022
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Equity Method Investments	Details of the Partnership’s equity method investments follows. December 31, 2022 December 31, 2021 (In thousands) Double E $ 281,640 $ 280,952 Ohio Gathering 225,037 242,244 Total $ 506,677 $ 523,196 Summarized balance sheet information for Double E follows (amounts represent 100% of investee financial information). December 31, 2022 December 31, 2021 (In thousands) Current assets $ 5,121 $ 12,353 Noncurrent assets 403,594 410,731 Total assets $ 408,715 $ 423,084 Current liabilities $ 8,635 $ 22,836 Noncurrent liabilities 9,137 10,281 Total liabilities $ 17,772 $ 33,117 Summarized statements of operations information for Double E follows (amounts represent 100% of investee financial information). Year Ended December 31, 2022 Year Ended December 31, 2021 (In thousands) Total revenues $ 32,418 $ 3,579 Total operating expenses 25,685 5,281 Net income (loss) $ 6,733 $ (1,702) A reconciliation of the difference between the carrying amount of the Partnership’s interest in Ohio Gathering and the Partnership’s underlying investment in Ohio Gathering, per Ohio Gathering’s books and records, is shown below. 2022 2021 (In thousands) Investment in Ohio Gathering, December 31 $ 225,037 $ 242,244 December cash distributions 2,673 2,222 Impairment loss — 1,971 Basis difference 199,263 207,927 Other — 137 Investment in Ohio Gathering (Books and records), November 30, $ 426,973 $ 454,501 Summarized balance sheet information for OGC and OCC follows (amounts represent 100% of investee financial information). November 30, 2022 November 30, 2021 OGC OCC OGC OCC (In thousands) Current assets $ 36,062 $ 5,195 $ 36,967 $ 5,300 Noncurrent assets 1,157,530 274 1,189,921 961 Total assets $ 1,193,592 $ 5,469 $ 1,226,888 $ 6,261 Current liabilities $ 6,942 $ 3,588 $ 7,984 $ 3,104 Noncurrent liabilities 13,380 3,096 9,854 4,927 Total liabilities $ 20,322 $ 6,684 $ 17,838 $ 8,031 Summarized statements of operations information for OGC and OCC follows (amounts represent 100% of investee financial information). Twelve months ended Twelve months ended OGC OCC OGC OCC (In thousands) Total revenues $ 113,317 $ 13,340 $ 102,140 $ 12,614 Total operating expenses 106,369 12,786 95,399 11,419 Net income (loss) 6,948 554 6,742 1,169

DEFERRED REVENUE (Tables)

DEFERRED REVENUE (Tables)	12 Months Ended
	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
Schedule of Rollforward Deferred Revenue	An update of current deferred revenue is as follows. (In thousands) Current deferred revenue, January 1, 2022 $ 10,374 Additions 4,578 Less: revenue recognized (5,898) Current deferred revenue, December 31, 2022 $ 9,054 An update of noncurrent deferred revenue follows. (In thousands) Noncurrent deferred revenue, January 1, 2022 $ 42,570 Additions 269 Less: reclassification to current deferred revenue and other (5,145) Noncurrent deferred revenue, December 31, 2022 $ 37,694

DEBT (Tables)

DEBT (Tables)	12 Months Ended
	Dec. 31, 2022
Debt Disclosure [Abstract]
Schedule of Debt	Debt for the Partnership at December 31, 2022 and 2021 follows. December 31, 2022 December 31, 2021 (In thousands) ABL Facility : Summit Holdings' asset based credit facility due May 1, 2026 $ 330,000 $ 267,000 Permian Transmission Credit Facility : Permian Transmission's variable rate senior secured credit facility due March 8, 2028 — 160,000 Permian Transmission Term Loan : Permian Transmission's variable rate senior secured term loan due January 2028 155,353 — 2025 Senior Notes : Summit Holdings' 5.75% senior unsecured notes due April 15, 2025 259,463 259,463 2026 Secured Notes : Summit Holdings' and Finance Corp's 8.50% senior second lien notes due October 15, 2026 785,000 700,000 Less: unamortized debt discount and debt issuance costs (39,454) (31,391) Total debt 1,490,362 1,355,072 Less: current portion of Permian Transmission Credit Facility (10,507) — Total long-term debt $ 1,479,855 $ 1,355,072
Schedule of Maturities of Long-Term Debt	The aggregate amount of Partnership’s debt maturing during each of the years after December 31, 2022 are as follows (in thousands): 2023 $ 10,507 2024 15,524 2025 276,043 2026 1,131,967 2027 17,769 Thereafter 78,006 Total long-term debt $ 1,529,816 (In thousands) Total 2023 2024 2025 2026 2027 Thereafter Amortizing principal repayments $ 155,353 $ 10,507 $ 15,524 $ 16,580 $ 16,967 $ 17,769 $ 78,006

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	12 Months Ended
	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Schedule of Accrued Environmental Remediation	A rollforward of the Partnership’s undiscounted accrued environmental remediation follows and is primarily related to the 2015 Blacktail Release and other environmental remediation activities. (In thousands) Accrued environmental remediation, December 31, 2020 $ 2,929 Payments made (1,972) Additional accruals 4,649 Accrued environmental remediation, December 31, 2021 $ 5,606 Payments made (2,746) Additional accruals 845 Accrued environmental remediation, December 31, 2022 $ 3,705

FINANCIAL INSTRUMENTS (Tables)

FINANCIAL INSTRUMENTS (Tables)	12 Months Ended
	Dec. 31, 2022
Fair Value Disclosures [Abstract]
Schedule of Estimated Fair Value of Debt Instruments	A summary of the estimated fair value of the Partnership’s debt financial instruments follows. December 31, 2022 December 31, 2021 Carrying Value (1) Estimated Carrying Value (1) Estimated (in thousands) 2025 Senior Notes 259,463 221,733 259,463 234,814 2026 Secured Notes 785,000 750,983 700,000 718,083 (1) Excludes applicable unamortized debt issuance costs and debt discounts.

PARTNERS' CAPITAL AND MEZZANI_2

PARTNERS' CAPITAL AND MEZZANINE CAPITAL (Tables)	12 Months Ended
	Dec. 31, 2022
Equity [Abstract]
Schedule of Partner Units Activity	An update on the number of common units is as follows for the period from December 31, 2020 to December 31, 2022. Common Units December 31, 2020 6,110,092 2021 Preferred Exchange Offer, net of units withheld for taxes 538,715 Common units issued for SMLP LTIP, net 106,580 ECP Warrant Exercise 414,447 December 31, 2021 7,169,834 2022 Preferred Exchange Offer, net of units withheld for taxes 2,853,875 Common units issued for SMLP LTIP, net 159,054 December 31, 2022 10,182,763 A rollforward of the number of outstanding Series A Preferred Units follows for the period from December 31, 2020 to December 31, 2022. Series A December 31, 2020 162,109 2021 Preferred Exchange Offer (18,662) December 31, 2021 143,447 2022 Preferred Exchange Offer (77,939) December 31, 2022 65,508
Schedule of Change in Subsidiary	The following table shows the change in the Partnership’s Subsidiary Series A Preferred Unit balance from January 1, 2021 through December 31, 2022, net of $2.2 million and $3.9 million of unamortized issuance costs at December 31, 2022 and December 31, 2021: (in thousands) Balance at January 1, 2021 $ 89,658 PIK distributions 6,131 Redemption accretion 10,536 Balance at December 31, 2021 $ 106,325 PIK distributions 1,600 Redemption accretion 15,544 Cash distribution (includes $1.6 million distributions payable as of December 31, 2022) $ (4,885) Balance at December 31, 2022 $ 118,584

EARNINGS PER UNIT (Tables)

EARNINGS PER UNIT (Tables)	12 Months Ended
	Dec. 31, 2022
Earnings Per Share [Abstract]
Schedule of Earnings Per Limited Partner Unit	The following table details the components of EPU. Year ended December 31, 2022 2021 (In thousands, except per-unit amounts) Numerator for basic and diluted EPU: Allocation of net income (loss) among limited partner interests: Net loss $ (123,461) $ (19,949) Less: Net income attributable to Subsidiary Series A Preferred Units (17,144) (16,667) Net loss attributable Summit Midstream Partners, LP (140,605) (36,616) Less: Net income attributable to Series A Preferred Unit (8,048) (15,998) Add: Deemed capital contribution 20,974 8,326 Net loss attributable to common limited partners $ (127,679) $ (44,288) Denominator for basic and diluted EPU: Weighted-average common units outstanding – basic 10,048 6,741 Effect of nonvested phantom units — — Weighted-average common units outstanding – diluted 10,048 6,741 Net Loss per limited partner unit: Common unit – basic $ (12.71) $ (6.57) Common unit – diluted $ (12.71) $ (6.57) Nonvested anti-dilutive phantom units excluded from the calculation of diluted EPU 177 203

SUPPLEMENTAL CASH FLOW INFORM_2

SUPPLEMENTAL CASH FLOW INFORMATION (Tables)	12 Months Ended
	Dec. 31, 2022
Supplemental Cash Flow Elements [Abstract]
Schedule of Supplemental Cash Flow Information	Year ended December 31, 2022 2021 (In thousands) Supplemental cash flow information: Cash interest paid $ 89,472 $ 57,655 Cash paid for taxes 149 191 Noncash investing and financing activities: Capital expenditures in trade accounts payable (period-end accruals) $ 6,724 $ 5,692 Accretion of Subsidiary Series A Preferred Units 15,544 10,536 Exercise of ECP Warrants — 15,542 2022 Preferred Exchange Offer 92,587 — 2021 Preferred Exchange Offer — 20,654

UNIT-BASED AND NONCASH COMPEN_2

UNIT-BASED AND NONCASH COMPENSATION (Tables)	12 Months Ended
	Dec. 31, 2022
Share-Based Payment Arrangement [Abstract]
Schedule of Activity	The following table presents phantom unit activity for the periods presented: Units Weighted-average grant date fair value Nonvested phantom units, December 31, 2020 291,691 $ 26.57 Phantom units granted 199,241 22.33 Phantom units vested (143,768) 30.66 Phantom units forfeited (13,385) 38.85 Nonvested phantom units, December 31, 2021 333,779 21.78 Phantom units granted 509,631 17.70 Phantom units vested (229,551) 23.61 Phantom units forfeited (8,717) 22.53 Nonvested phantom units, December 31, 2022 605,142 $ 17.62
Schedule of Intrinsic Values	The intrinsic value of phantom units that vested during the years ended December 31, follows. Year ended December 31, 2022 2021 (In thousands) Intrinsic value of vested LTIP awards $ 5,420 $ 4,407
Schedule of Unit-Based Compensation Recognized in General and Administrative Expense	Unit-based compensation recognized in general and administrative expense related to awards under the SMLP LTIP follows. Year ended December 31, 2022 2021 (In thousands) SMLP LTIP unit-based compensation $ 3,778 $ 4,744

LEASES (Tables)

LEASES (Tables)	12 Months Ended
	Dec. 31, 2022
Leases [Abstract]
Schedule of Right-Of-Use Assets and Lease Liabilities	ROU assets (included in the other noncurrent assets Other current liabilities Other noncurrent liabilities December 31, 2022 December 31, 2021 (In thousands) ROU assets Operating $ 11,633 $ 2,515 Finance 1,389 792 $ 13,022 $ 3,307 Lease liabilities, current Operating $ 2,570 $ 1,213 Finance 435 167 $ 3,005 $ 1,380 Lease liabilities, noncurrent Operating $ 9,672 $ 2,272 Finance 679 122 $ 10,351 $ 2,394
Schedule of Lease Cost and Other Information	Lease cost and Other information follow: Year ended December 31, 2022 2021 (In thousands) Lease cost Finance lease cost: Amortization of ROU assets (included in depreciation and amortization) $ 673 $ 1,026 Interest on lease liabilities (included in interest expense) 18 20 Operating lease cost (included in general and administrative expense) 1,815 1,722 $ 2,506 $ 2,768 Year ended December 31, 2022 2021 (In thousands) Other information Cash paid for amounts included in the measurement of lease liabilities Operating cash outflows from operating leases $ 1,732 $ 1,407 Operating cash outflows from finance leases 18 20 Financing cash outflows from finance leases 330 634 ROU assets obtained in exchange for new operating lease liabilities 9,865 — ROU assets obtained in exchange for new finance lease liabilities 1,298 94 Weighted-average remaining lease term (years) - operating leases 4.7 5.1 Weighted-average remaining lease term (years) - finance leases 2.4 1.1 Weighted-average discount rate - operating leases 6 % 5 % Weighted-average discount rate - finance leases 3 % 4 % The Partnership recognizes total lease expense incurred or allocated to us in general and administrative expenses. Lease expense related to operating leases, including lease expense incurred on the Partnership’s behalf and allocated to us, was as follows: Year ended December 31, 2022 2021 (In thousands) Lease expense $ 3,162 $ 2,479
Schedule of Future Minimum Lease Payments Due and Future Minimum Rentals to be Received Under Noncancelable Leases and Subleases	Future minimum lease payments due under noncancelable leases at December 31, 2022, were as follows: December 31, 2022 (In thousands) Operating Finance 2023 $ 4,026 $ 538 2024 3,650 489 2025 3,486 276 2026 2,646 7 2027 2,280 — 2028 61 — Thereafter 357 — Total future minimum lease payments $ 16,506 $ 1,310

SEGMENT INFORMATION (Tables)

SEGMENT INFORMATION (Tables)	12 Months Ended
	Dec. 31, 2022
Segment Reporting [Abstract]
Schedule of Assets by Reportable Segment	Assets by reportable segment follow. December 31, 2022 2021 (in thousands) Assets: Northeast $ 591,091 $ 623,224 Rockies 886,629 592,148 Permian 298,906 458,988 Piceance 475,719 524,218 Barnett 295,473 315,055 Total reportable segment assets 2,547,818 2,513,633 Corporate and Other 12,146 8,829 Total assets $ 2,559,964 $ 2,522,462
Schedule of Segment Reporting Information	Revenues by reportable segment follow. Year ended December 31, 2022 2021 (In thousands) Revenues: Northeast $ 54,392 $ 62,567 Rockies 143,603 145,087 Permian 25,151 40,848 Piceance 93,349 105,485 Barnett 52,096 46,591 Total reportable segments revenue 368,591 400,578 Corporate and Other 1,003 40 Total revenues $ 369,594 $ 400,618 Depreciation and amortization, including the amortization expense associated with the Partnership’s favorable and unfavorable gas gathering contracts as reported in other revenues, by reportable segment follow. Year ended December 31, 2022 2021 (In thousands) Depreciation and amortization: Northeast $ 17,501 $ 17,054 Rockies 30,532 29,513 Permian 2,736 5,858 Piceance 51,352 48,773 Barnett (1) 16,116 16,133 Total reportable segment depreciation and amortization 118,237 117,331 Corporate and Other 1,756 2,664 Total depreciation and amortization $ 119,993 $ 119,995 ______________________________________ (1) Includes the amortization expense associated with the Partnership’s favorable and unfavorable gas gathering contracts as reported in Other revenues. Cash paid for capital expenditures by reportable segment follow. Year ended December 31, 2022 2021 (In thousands) Cash paid for capital expenditures: Northeast $ 8,743 $ 11,237 Rockies 11,903 9,875 Permian 1,407 2,042 Piceance 6,116 579 Barnett 366 766 Total reportable segment capital expenditures 28,535 24,499 Corporate and Other 1,937 531 Total cash paid for capital expenditures $ 30,472 $ 25,030
Schedule of Counterparties Accounting for More than 10% of Total Revenues	Counterparties accounting for a significant portion of total revenues were as follows: Year ended December 31, 2022 2021 Percentage of total revenues (1) : Counterparty A - Piceance 13 % 12 % ________________________________________________________
Schedule of Reconciliation of Net Income to Adjusted EBITDA	Segment adjusted EBITDA by reportable segment follows. Year ended December 31, 2022 2021 (In thousands) Reportable segment adjusted EBITDA Northeast $ 77,046 $ 83,287 Rockies 57,810 64,517 Permian 18,051 6,614 Piceance 60,055 76,131 Barnett 31,624 36,729 Total of reportable segments' measures of profit $ 244,586 $ 267,278 A reconciliation of income or loss before income taxes and income or loss from equity method investees to total of reportable segments' measures of profit or loss follows. Year ended December 31, 2022 2021 (In thousands) Reconciliation of income (loss) before income taxes and income (loss) from equity method investees to total of reportable segments' measures of profit: Loss before income taxes and income from equity method investees $ (141,277) $ (28,156) Add: Corporate and Other expense 29,118 68,783 Interest expense 102,459 66,156 Gain on early extinguishment of debt — 3,523 Depreciation and amortization (1) 119,993 119,995 Proportional adjusted EBITDA for equity method investees 45,419 29,022 Adjustments related to capital reimbursement activity (6,041) (6,571) Unit-based and noncash compensation 3,778 4,744 Gain on asset sales, net (507) (369) Long-lived asset impairment 91,644 10,151 Total of reportable segments' measures of profit $ 244,586 $ 267,278 ______________________________________ (1) Includes the amortization expense associated with the Partnership’s favorable gas gathering contracts as reported in other revenues.

SUMMARY OF SIGNIFICANT ACCOUN_4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Summary of Significant Accounting Policies [Line Items]
Restricted cash	$ 1,723	$ 12,223
Favorable gas gathering contracts | Minimum
Summary of Significant Accounting Policies [Line Items]
Useful lives (In years)	10 years
Favorable gas gathering contracts | Maximum
Summary of Significant Accounting Policies [Line Items]
Useful lives (In years)	20 years
Other Gas Gathering Contract | Minimum
Summary of Significant Accounting Policies [Line Items]
Useful lives (In years)	3 years
Other Gas Gathering Contract | Maximum
Summary of Significant Accounting Policies [Line Items]
Useful lives (In years)	25 years
Rights-of-way | Minimum
Summary of Significant Accounting Policies [Line Items]
Useful lives (In years)	20 years
Rights-of-way | Maximum
Summary of Significant Accounting Policies [Line Items]
Useful lives (In years)	30 years

SUMMARY OF SIGNIFICANT ACCOUN_5

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property, Plant and Equipment (Details)	12 Months Ended
	Dec. 31, 2022
Gathering and processing systems and related equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful life (in years)	12 years
Gathering and processing systems and related equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful life (in years)	30 years
Other | Minimum
Property, Plant and Equipment [Line Items]
Useful life (in years)	4 years
Other | Maximum
Property, Plant and Equipment [Line Items]
Useful life (in years)	15 years

ACQUISTIONS AND DIVESTITURES -

ACQUISTIONS AND DIVESTITURES - Narratives (Details) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
	Dec. 01, 2022	Dec. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Sep. 19, 2022	Jun. 30, 2022
Double E
Business Acquisition [Line Items]
Percentage of ownership interest (as a percent)		70%	70%
Bison Midstream, LLC
Business Acquisition [Line Items]
Proceeds from sale of business, net of cash sold in transaction			$ 38,920	$ 0
Lane G&P System
Business Acquisition [Line Items]
Proceeds from sale of business, net of cash sold in transaction			75,020	$ 0
Disposal, not discontinued operations | Bison Midstream, LLC
Business Acquisition [Line Items]
Cash consideration					$ 40,000
Impairment on disposition			6,900
Proceeds from sale of business, net of cash sold in transaction			38,900
Net book value of assets and liabilities divested		$ 45,800	45,800
Disposal, not discontinued operations | Lane G&P System
Business Acquisition [Line Items]
Cash consideration						$ 75,000
Impairment on disposition			84,500
Proceeds from sale of business, net of cash sold in transaction			75,000
Net book value of assets and liabilities divested		158,300	158,300
Cash sold, working capital and other miscellaneous adjustments			2,000
Other costs to sell			$ 1,200
Outrigger DJ
Business Acquisition [Line Items]
Ownership interest (as a percent)	100%
Cash paid to acquire investment	$ 165,000
Weighted average amortization period	30 years
Revenue of acquired business since acquisition		8,400
Earnings of acquired business since acquisition		1,800
Intangible assets	$ 21,447
Sterling DJ
Business Acquisition [Line Items]
Ownership interest (as a percent)	100%
Cash paid to acquire investment	$ 140,000
Weighted average amortization period	30 years
Revenue of acquired business since acquisition		7,900
Earnings of acquired business since acquisition		$ 100
Intangible assets	$ 38,678
Sterling DJ | Rights-Of-Way Intangibles
Business Acquisition [Line Items]
Intangible assets	30,200
Sterling DJ | Water Rights Intangibles
Business Acquisition [Line Items]
Intangible assets	$ 8,400

ACQUISTIONS AND DIVESTITURES _2

ACQUISTIONS AND DIVESTITURES - Schedule of Fair Value of the Assets and Liabilities Acquired (Details) $ in Thousands	Dec. 01, 2022 USD ($)
Outrigger DJ
Business Acquisition [Line Items]
Consideration paid	$ 167,631
Cash	1,000
Accounts receivable	7,529
Other current assets	190
Property, plant and equipment, net	144,514
Intangible assets	21,447
Trade accounts payable, accrued expenses and other	(7,049)
Net assets acquired and liabilities assumed	167,631
Sterling DJ
Business Acquisition [Line Items]
Consideration paid	140,396
Cash	500
Accounts receivable	16,224
Other current assets	4,557
Property, plant and equipment, net	108,720
Intangible assets	38,678
Other noncurrent assets	9,865
Trade accounts payable, accrued expenses and other	(38,148)
Net assets acquired and liabilities assumed	$ 140,396

ACQUISTIONS AND DIVESTITURES _3

ACQUISTIONS AND DIVESTITURES - Schedule of Pro Forma Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Business Combination and Asset Acquisition [Abstract]
Revenues	$ 543,024	$ 471,787
Net loss	$ (36,945)	$ (35,396)

REVENUE - Schedule of Estimated

REVENUE - Schedule of Estimated Revenue Expected to be Recognized (Details) - Gathering services and related fees $ in Thousands	Dec. 31, 2022 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 78,245
Revenue, remaining performance obligation, expected timing of satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 67,079
Revenue, remaining performance obligation, expected timing of satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 46,803
Revenue, remaining performance obligation, expected timing of satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 30,527
Revenue, remaining performance obligation, expected timing of satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 9,038
Revenue, remaining performance obligation, expected timing of satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2028-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 6,042
Revenue, remaining performance obligation, expected timing of satisfaction, Period	1 year

REVENUE - Schedule of Disaggreg

REVENUE - Schedule of Disaggregated Revenue by Geographic Area and Major Products and Services Reportable Segments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Total revenues	$ 369,594	$ 400,618
All Other Segments
Disaggregation of Revenue [Line Items]
Total revenues	1,003	40
Gathering services and related fees
Disaggregation of Revenue [Line Items]
Total revenues	248,358	281,705
Gathering services and related fees | All Other Segments
Disaggregation of Revenue [Line Items]
Total revenues	0	0
Natural gas, NGLs and condensate sales
Disaggregation of Revenue [Line Items]
Total revenues	86,225	82,768
Natural gas, NGLs and condensate sales | All Other Segments
Disaggregation of Revenue [Line Items]
Total revenues	21	0
Other revenues
Disaggregation of Revenue [Line Items]
Total revenues	35,011	36,145
Other revenues | All Other Segments
Disaggregation of Revenue [Line Items]
Total revenues	982	40
Reportable Segments
Disaggregation of Revenue [Line Items]
Total revenues	368,591	400,578
Reportable Segments | Northeast
Disaggregation of Revenue [Line Items]
Total revenues	54,392	62,567
Reportable Segments | Rockies
Disaggregation of Revenue [Line Items]
Total revenues	143,603	145,087
Reportable Segments | Permian
Disaggregation of Revenue [Line Items]
Total revenues	25,151	40,848
Reportable Segments | Piceance
Disaggregation of Revenue [Line Items]
Total revenues	93,349	105,485
Reportable Segments | Barnett
Disaggregation of Revenue [Line Items]
Total revenues	52,096	46,591
Reportable Segments | Gathering services and related fees
Disaggregation of Revenue [Line Items]
Total revenues	248,358	281,705
Reportable Segments | Gathering services and related fees | Northeast
Disaggregation of Revenue [Line Items]
Total revenues	54,392	62,567
Reportable Segments | Gathering services and related fees | Rockies
Disaggregation of Revenue [Line Items]
Total revenues	67,838	74,823
Reportable Segments | Gathering services and related fees | Permian
Disaggregation of Revenue [Line Items]
Total revenues	3,668	8,230
Reportable Segments | Gathering services and related fees | Piceance
Disaggregation of Revenue [Line Items]
Total revenues	80,630	95,235
Reportable Segments | Gathering services and related fees | Barnett
Disaggregation of Revenue [Line Items]
Total revenues	41,830	40,850
Reportable Segments | Natural gas, NGLs and condensate sales
Disaggregation of Revenue [Line Items]
Total revenues	86,204	82,768
Reportable Segments | Natural gas, NGLs and condensate sales | Northeast
Disaggregation of Revenue [Line Items]
Total revenues	0	0
Reportable Segments | Natural gas, NGLs and condensate sales | Rockies
Disaggregation of Revenue [Line Items]
Total revenues	59,208	48,279
Reportable Segments | Natural gas, NGLs and condensate sales | Permian
Disaggregation of Revenue [Line Items]
Total revenues	17,382	28,727
Reportable Segments | Natural gas, NGLs and condensate sales | Piceance
Disaggregation of Revenue [Line Items]
Total revenues	7,111	5,464
Reportable Segments | Natural gas, NGLs and condensate sales | Barnett
Disaggregation of Revenue [Line Items]
Total revenues	2,503	298
Reportable Segments | Other revenues
Disaggregation of Revenue [Line Items]
Total revenues	34,029	36,105
Reportable Segments | Other revenues | Northeast
Disaggregation of Revenue [Line Items]
Total revenues	0	0
Reportable Segments | Other revenues | Rockies
Disaggregation of Revenue [Line Items]
Total revenues	16,557	21,985
Reportable Segments | Other revenues | Permian
Disaggregation of Revenue [Line Items]
Total revenues	4,101	3,891
Reportable Segments | Other revenues | Piceance
Disaggregation of Revenue [Line Items]
Total revenues	5,608	4,786
Reportable Segments | Other revenues | Barnett
Disaggregation of Revenue [Line Items]
Total revenues	$ 7,763	$ 5,443

PROPERTY, PLANT, AND EQUIPMEN_2

PROPERTY, PLANT, AND EQUIPMENT - Schedule of Property, Plant, and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 2,395,344	$ 2,336,856
Less accumulated depreciation	(676,590)	(610,774)
Property, plant and equipment, net	1,718,754	1,726,082
Gathering and processing systems and related equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	2,262,330	2,225,267
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	59,036	49,082
Land and line fill
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	11,756	10,644
Other
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 62,222	$ 51,863

PROPERTY, PLANT, AND EQUIPMEN_3

PROPERTY, PLANT, AND EQUIPMENT - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Impairment of property, plant and equipment	$ 91.6	$ 10.2

PROPERTY, PLANT, AND EQUIPMEN_4

PROPERTY, PLANT, AND EQUIPMENT - Schedule of Depreciation Expense and Capitalized Interest (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 93,457	$ 90,711
Capitalized interest	$ 838	$ 1,534

INTANGIBLE ASSETS - Intangible

INTANGIBLE ASSETS - Intangible Assets and Liabilities Subject to Amortization (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount		$ 462,559
Accumulated amortization	$ (301,282)	(289,632)
Net	190,282	172,927
Indefinite-lived intangibles	8,436
Total intangibles, gross	500,000
Total intangibles, net	198,718	172,927
Favorable gas gathering contracts
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	21,063	24,195
Accumulated amortization	(14,809)	(17,002)
Net	6,254	7,193
Contract intangibles
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	270,412	278,448
Accumulated amortization	(228,143)	(217,245)
Net	42,269	61,203
Rights-of-way
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	200,089	159,916
Accumulated amortization	(58,330)	(55,385)
Net	$ 141,759	$ 104,531

INTANGIBLE ASSETS - Recognized

INTANGIBLE ASSETS - Recognized Amortization Expense in Other Revenues and Cost and Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Other Revenue | Favorable gas gathering contracts
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 938	$ 938
Costs And Expenses | Contract intangibles
Finite-Lived Intangible Assets [Line Items]
Amortization expense	18,935	22,002
Costs And Expenses | Rights-of-way
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 6,527	$ 6,344

INTANGIBLE ASSETS - Estimated A

INTANGIBLE ASSETS - Estimated Aggregate Annual Amortization Expected to be Recognized (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
2023	$ 27,749
2024	17,563
2025	17,379
2026	14,354
2027	8,365
Thereafter	104,872
Net	$ 190,282	$ 172,927

EQUITY METHOD INVESTMENTS - Sch

EQUITY METHOD INVESTMENTS - Schedule of Equity Method Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Investment in equity method investees	$ 506,677	$ 523,196
Double E
Schedule of Equity Method Investments [Line Items]
Investment in equity method investees	281,640	280,952
Ohio Gathering
Schedule of Equity Method Investments [Line Items]
Investment in equity method investees	$ 225,037	$ 242,244

EQUITY METHOD INVESTMENTS - Nar

EQUITY METHOD INVESTMENTS - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Investment in Double E equity method investee	$ (8,444)	$ (148,699)
Distributions from equity method investees	$ 43,040	26,760
Double E
Schedule of Equity Method Investments [Line Items]
Percentage of ownership interest (as a percent)	70%
Investment in Double E equity method investee	$ (8,400)	(148,700)
Capitalized interest paid	0	$ 3,000
Distribution made to partnership from total distributions	12,500
Distributions from equity method investees	$ 17,800
OGC | Principal Owner
Schedule of Equity Method Investments [Line Items]
Percentage of ownership interest (as a percent)	37.20%	37.80%
OCC | Principal Owner
Schedule of Equity Method Investments [Line Items]
Percentage of ownership interest (as a percent)	38.20%	38.20%

EQUITY METHOD INVESTMENTS - Bal

EQUITY METHOD INVESTMENTS - Balance Sheet Information (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Nov. 30, 2022	Dec. 31, 2021	Nov. 30, 2021
Schedule of Equity Method Investments [Line Items]
Current assets	$ 97,542		$ 87,369
TOTAL ASSETS	2,559,964		2,522,462
Current liabilities	117,889		79,237
Total liabilities	1,676,562		1,511,774
Equity Method Investment, Nonconsolidated Investee or Group of Investees
Schedule of Equity Method Investments [Line Items]
Current assets	5,121		12,353
Noncurrent assets	403,594		410,731
TOTAL ASSETS	408,715		423,084
Current liabilities	8,635		22,836
Noncurrent liabilities	9,137		10,281
Total liabilities	$ 17,772		$ 33,117
OGC
Schedule of Equity Method Investments [Line Items]
Current assets		$ 36,062		$ 36,967
Noncurrent assets		1,157,530		1,189,921
TOTAL ASSETS		1,193,592		1,226,888
Current liabilities		6,942		7,984
Noncurrent liabilities		13,380		9,854
Total liabilities		20,322		17,838
OCC
Schedule of Equity Method Investments [Line Items]
Current assets		5,195		5,300
Noncurrent assets		274		961
TOTAL ASSETS		5,469		6,261
Current liabilities		3,588		3,104
Noncurrent liabilities		3,096		4,927
Total liabilities		$ 6,684		$ 8,031

EQUITY METHOD INVESTMENTS - Sta

EQUITY METHOD INVESTMENTS - Statements of Operations Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Nov. 30, 2022	Dec. 31, 2021	Nov. 30, 2021
Schedule of Equity Method Investments [Line Items]
Net loss	$ (123,461)		$ (19,949)
Equity Method Investment, Nonconsolidated Investee or Group of Investees
Schedule of Equity Method Investments [Line Items]
Total revenues	32,418		3,579
Total operating expenses	25,685		5,281
Net loss	$ 6,733		$ (1,702)
Ohio Gathering
Schedule of Equity Method Investments [Line Items]
Total revenues		$ 113,317		$ 102,140
Total operating expenses		106,369		95,399
Net loss		6,948		6,742
OCC
Schedule of Equity Method Investments [Line Items]
Total revenues		13,340		12,614
Total operating expenses		12,786		11,419
Net loss		$ 554		$ 1,169

EQUITY METHOD INVESTMENTS - Rol

EQUITY METHOD INVESTMENTS - Rollforward of the Investment in Equity Method Investees (Details) - USD ($) $ in Thousands	11 Months Ended		12 Months Ended
	Nov. 30, 2022	Nov. 30, 2021	Dec. 31, 2022	Dec. 31, 2021
Equity Method Investment [Roll Forward]
Beginning balance	$ 523,196		$ 523,196
December cash distributions			43,040	$ 26,760
Ending balance			506,677	523,196
Ohio Gathering
Equity Method Investment [Roll Forward]
Beginning balance	242,244		242,244
Ending balance			225,037	242,244
Ohio Gathering | Summit Midstream Partners, LLC
Equity Method Investment [Roll Forward]
Beginning balance	225,037	$ 242,244	$ 225,037	242,244
December cash distributions	2,673	2,222
Impairment loss	0	1,971
Basis difference	199,263	207,927
Other	0	137
Ending balance	$ 426,973	$ 454,501		$ 225,037

DEFERRED REVENUE (Details)

DEFERRED REVENUE (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($)
Change in Contract With Customer, Liability, Current [Roll Forward]
Beginning balance	$ 10,374
Additions	4,578
Less: revenue recognized	(5,898)
Ending balance	9,054
Change in Contract With Customer, Liability, Noncurrent [Roll Forward]
Beginning balance	42,570
Additions	269
Less: reclassification to current deferred revenue and other	(5,145)
Ending balance	$ 37,694

DEBT - Components of Long-Term

DEBT - Components of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Line of Credit Facility [Line Items]
Total	$ 1,529,816
Less: unamortized debt discount and debt issuance costs	(39,454)	$ (31,391)
Total debt	1,490,362	1,355,072
Less: current portion of Permian Transmission Credit Facility	(10,507)	0
Total long-term debt	1,479,855	1,355,072
Asset Backed Lending Facility | Line of Credit
Line of Credit Facility [Line Items]
Secured notes	330,000	267,000
Permian Transmission Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Secured notes	0	160,000
Permian Transmission Term Loan
Line of Credit Facility [Line Items]
Total	155,353
Permian Transmission Term Loan | Line of Credit
Line of Credit Facility [Line Items]
Total	$ 155,353	0
2025 Senior Notes
Line of Credit Facility [Line Items]
Stated interest rate (as a percent)	5.75%
2025 Senior Notes | Senior Notes
Line of Credit Facility [Line Items]
Unsecured notes	$ 259,463	259,463
2026 Secured Notes
Line of Credit Facility [Line Items]
Stated interest rate (as a percent)	8.50%
2026 Secured Notes | Term Loan
Line of Credit Facility [Line Items]
Unsecured notes	$ 785,000	$ 700,000

DEBT - Schedule of Maturities (

DEBT - Schedule of Maturities (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Line of Credit Facility [Line Items]
Total	$ 1,529,816
2023	10,507
2024	15,524
2025	276,043
2026	1,131,967
2027	17,769
Thereafter	78,006
Permian Transmission Term Loan
Line of Credit Facility [Line Items]
Total	155,353
2023	10,507
2024	15,524
2025	16,580
2026	16,967
2027	17,769
Thereafter	$ 78,006

DEBT - Narrative (Details)

DEBT - Narrative (Details)			12 Months Ended
	Dec. 31, 2022 USD ($)	Nov. 02, 2021 USD ($)	Dec. 31, 2022 USD ($)	Nov. 30, 2022 USD ($)	Oct. 14, 2022 USD ($)	Dec. 31, 2021 USD ($)	Mar. 08, 2021 USD ($)	Jan. 01, 2021
Revolving credit facility | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)			3.25%
ABL Facility
Debt Instrument [Line Items]
Borrowing capacity		$ 400,000,000
Borrowing base	$ 561,000,000		$ 561,000,000
Interest rate (as a percent)			7.45%
Unused portion under the facility					$ 64,100,000
Secured notes					$ 5,900,000
Maximum amount of debt outstanding for maturity to occur		$ 50,000,000
Mandatory redemption period (in days)		120 days
Covenant, first lien net leverage ratio	1.31	2.50	1.31
Covenant, interest coverage ratio	2.52	2	2.52
Credit Agreement
Debt Instrument [Line Items]
Borrowing capacity							$ 175,000,000
Effective interest rate (as a percent)	6.05%		6.05%
Unused borrowing capacity amount	$ 4,500,000		$ 4,500,000
Credit Agreement | Standby Letters of Credit
Debt Instrument [Line Items]
Unused borrowing capacity amount	$ 10,500,000		$ 10,500,000
Credit Agreement | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)			2.375%
Commitment fee (as a percent)			0.70%
Credit Agreement | Term Loan Credit Facility
Debt Instrument [Line Items]
Borrowing capacity							160,000,000
Credit Agreement | Working Capital Credit Facility
Debt Instrument [Line Items]
Borrowing capacity							$ 15,000,000
Permian Transmission Term Loan
Debt Instrument [Line Items]
Effective interest rate (as a percent)	6.05%		6.05%
Permian Transmission Term Loan | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	1.49%		2.375%
2026 Notes
Debt Instrument [Line Items]
Debt instrument, amount				$ 85,000,000		$ 700,000,000
Stated interest rate (as a percent)								8.50%
Debt instrument issued as a percentage of face value (as a percent)				99.26%		98.50%
2025 Senior Notes
Debt Instrument [Line Items]
Maximum amount of debt outstanding for maturity to occur		$ 50,000,000
Mandatory redemption period (in days)		91 days
2025 Senior Notes | Redemption period two | Summit Holdings and Finance Corporation
Debt Instrument [Line Items]
Redemption price, expressed as percentage of principal amount (as a percent)			101.438%
2025 Senior Notes | Redemption period three | Summit Holdings and Finance Corporation
Debt Instrument [Line Items]
Redemption price, expressed as percentage of principal amount (as a percent)			100%
Secured Notes Indenture, 2026
Debt Instrument [Line Items]
Interest rate (as a percent)			9%
Redemption price, percentage of principal amount redeemed (as a percent)		35%
Redemption price, expressed as percentage of principal amount (as a percent)		108.50%
Covenant redemption, percent of initial principal amount remaining outstanding		65%
Ownership percentage of principal (as a percent)		25%
Repurchase amount of principal plus accrued interest (as a percent)		100%
Excess cash flow offer to purchase, period one		$ 50,000,000
Excess ash flow offer to purchase, basis point increase, period one	0.50%	0.50%	0.50%
Excess cash flow offer to purchase, period two		$ 100,000,000
Excess cash flow offer to purchase, basis point increase, period two		1%
Excess cash flow offer to purchase, period three		$ 200,000,000
Excess cash flow offer to purchase, basis point increase, period three		2%
Interest expense			$ 3,900,000
Secured Notes Indenture, 2026 | Redemption period one
Debt Instrument [Line Items]
Redemption price, expressed as percentage of principal amount (as a percent)		104.25%
Secured Notes Indenture, 2026 | Redemption period two
Debt Instrument [Line Items]
Redemption price, expressed as percentage of principal amount (as a percent)		102.125%
Secured Notes Indenture, 2026 | Redemption period three
Debt Instrument [Line Items]
Redemption price, expressed as percentage of principal amount (as a percent)		100%
2025 Senior Notes
Debt Instrument [Line Items]
Stated interest rate (as a percent)	5.75%		5.75%

DEBT - Schedule of Maturities o

DEBT - Schedule of Maturities of Long-Term Debt (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Total	$ 1,529,816
2023	10,507
2024	15,524
2025	276,043
2026	1,131,967
2027	17,769
Thereafter	78,006
Permian Transmission Term Loan
Debt Instrument [Line Items]
Total	155,353
2023	10,507
2024	15,524
2025	16,580
2026	16,967
2027	17,769
Thereafter	$ 78,006

COMMITMENTS AND CONTINGENCIES -

COMMITMENTS AND CONTINGENCIES - Rollforward of Environmental Matters (Details) - Meadowlark Midstream Gathering System - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Accrual for Environmental Loss Contingencies [Roll Forward]
Accrued environmental remediation, beginning balance	$ 5,606	$ 2,929
Payments made	(2,746)	(1,972)
Additional accruals	845	4,649
Accrued environmental remediation, ending balance	$ 3,705	$ 5,606

COMMITMENTS AND CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) claim	Dec. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)
Loss Contingencies [Line Items]
Legal fines and other fees	$ 36,300
Claims settled | claim	1
Sterling DJ
Loss Contingencies [Line Items]
Appeal bond acquired		$ 3,900
2015 Blacktail Release
Loss Contingencies [Line Items]
Loss contingency accrual	$ 28,300		$ 33,200
Unpaid penalties and fines, fixed rate (as a percent)	3.25%
Expected payment	$ 6,700
Claims settled | claim	1
Pending claims | claim	2
2015 Blacktail Release | Natural Resource Damages To Federal and State Governments
Loss Contingencies [Line Items]
Legal fines and other fees	$ 1,250
Penalties and fines, payment period	5 years
2015 Blacktail Release | Damages Payable To Federal Government over Five Years
Loss Contingencies [Line Items]
Legal fines and other fees	$ 25,000
2015 Blacktail Release | Damages Payable To State Governments Over Six Years
Loss Contingencies [Line Items]
Legal fines and other fees	$ 10,000
Penalties and fines, payment period	6 years

FINANCIAL INSTRUMENTS - Narrati

FINANCIAL INSTRUMENTS - Narrative (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) customer	Dec. 31, 2021	Mar. 08, 2021 USD ($)
CONCENTRATIONS OF RISK
Number of top customers | customer	5
Fair Value, Inputs, Level 3
CONCENTRATIONS OF RISK
Deferred earn-out liability	$ 5,200,000
Interest Rate Swap
CONCENTRATIONS OF RISK
Derivative instrument, notional amount			$ 139,800,000
Fair value of interest rate swap	$ 15,200,000
Five Largest Customers | Accounts receivable | Customer Concentration Risk
CONCENTRATIONS OF RISK
Concentration risk (as a percent)	26%	38%

FINANCIAL INSTRUMENTS - Fair va

FINANCIAL INSTRUMENTS - Fair value of Debt Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Carrying Value | 2025 Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes	$ 259,463	$ 259,463
Carrying Value | 2026 Secured Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes	785,000	700,000
Fair Value | 2025 Senior Notes | Estimated fair value (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes	221,733	234,814
Fair Value | 2026 Secured Notes | Estimated fair value (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes	$ 750,983	$ 718,083

PARTNERS' CAPITAL AND MEZZANI_3

PARTNERS' CAPITAL AND MEZZANINE CAPITAL - Partners' Capital and Schedule of Units (Details) - shares	1 Months Ended		12 Months Ended
	Jan. 31, 2022	Apr. 30, 2021	Dec. 31, 2022	Dec. 31, 2021
Common Units
Rollforwards of the number of partner units
Beginning balance (in shares)	7,169,834		7,169,834	6,110,092
Preferred Exchange Offer, net of units withheld for taxes (in shares)	2,853,875	538,715	2,853,875	538,715
Common units issued for SMLP LTIP, net (in shares)			159,054	106,580
ECP Warrant Exercise (in shares)				414,447
Ending balance (in shares)			10,182,763	7,169,834
Series A Preferred Units
Rollforwards of the number of partner units
Beginning balance (in shares)	143,447		143,447	162,109
Preferred Unit Exchange Offer (in shares)			(77,939)	(18,662)
Ending balance (in shares)			65,508	143,447

PARTNERS' CAPITAL AND MEZZANI_4

PARTNERS' CAPITAL AND MEZZANINE CAPITAL - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands				1 Months Ended			12 Months Ended
	Dec. 15, 2022	May 28, 2020	Jan. 21, 2020	Jan. 31, 2022	Apr. 30, 2021	Nov. 30, 2017	Dec. 31, 2022	Dec. 31, 2021	Aug. 05, 2021
Partners Capital [Line Items]
Add: deemed capital contribution				$ 92,600	$ 20,700		$ 20,974	$ 8,326
Gain (loss) on warrant exercise								$ 13,600
Maximum period following end of quarter to distribute all available cash							45 days
Subsidiary Series A Preferred Units
Partners Capital [Line Items]
Preferred units issued (in shares)							93,039,000	91,439,000
Preferred units issued during period (in shares)							1,600,000	6,131,000
Subsidiary Series A preferred unitholders, outstanding (in shares)							93,039,000	91,439,000
Common units
Partners Capital [Line Items]
Common units, issued (in shares)									414,447
Common units | Energy Capital Partners
Partners Capital [Line Items]
Exercise price of warrants (in dollars per share)		$ 15.35
Valuation of warrants		$ 2,300
Common units | SMLP Common Units | Energy Capital Partners
Partners Capital [Line Items]
Number of common units purchased (in shares)		537,307
Common units | SMLP Common Units | Energy Capital Partners | ECP Holdings Warrant
Partners Capital [Line Items]
Number of common units purchased (in shares)		129,360
Common Units
Partners Capital [Line Items]
General partner units converted (in shares)				2,853,875	538,715		2,853,875	538,715
Series A Preferred Units
Partners Capital [Line Items]
Preferred units issued (in shares)				77,939	18,662	300,000
Interest in partnership per unit (in dollars per share)						$ 1,000
Distribution rate (as a percent)						9.50%	7%
Liquidation preference per unit (in dollars per share)						$ 1,000	$ 1,000
Dividends payable							$ 21,500
Redemption amount							$ 119,900
Series A Preferred Units | Paid-in-kind
Partners Capital [Line Items]
Distribution percentage of subsidiary unit (as a percent)			7%
Distribution percentage of liquidation preference rate of undrawn commitment units (as a percent)			1%
Series A Preferred Units | LIBOR
Partners Capital [Line Items]
Basis spread on variable rate (as a percent)	12.20%					7.43%

PARTNERS' CAPITAL AND MEZZANI_5

PARTNERS' CAPITAL AND MEZZANINE CAPITAL - Change in Subsidiary Series A Preferred Unit Balance (Details) - Series A Preferred Units - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Partners Capital [Line Items]
Issuance costs	$ 2,200	$ 3,900
Rollforwards of the number of partner units
Beginning Balance	106,325	89,658
PIK distributions	1,600	6,131
Redemption accretion	15,544	10,536
Cash distribution (includes $1.6 million distributions payable as of December 31, 2022)	(4,885)
Ending Balance	118,584	$ 106,325
Distribution payable	$ 1,600

EARNINGS PER UNIT (Details)

EARNINGS PER UNIT (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	1 Months Ended		12 Months Ended
	Jan. 31, 2022	Apr. 30, 2021	Dec. 31, 2022	Dec. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net loss			$ (123,461)	$ (19,949)
Net loss attributable to Summit Midstream Partners, LP			(140,605)	(36,616)
Add: deemed capital contribution	$ 92,600	$ 20,700	$ 20,974	$ 8,326
Phantom Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Nonvested anti-dilutive phantom units excluded from the calculation of diluted EPU (in shares)			177	203
Series A Preferred Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss) attributable to limited partners			$ (8,048)	$ (15,998)
Series A Preferred Units | Subsidiaries
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss) attributable to limited partners			(17,144)	(16,667)
Common units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss) attributable to limited partners			$ (127,679)	$ (44,288)
Weighted-average common units outstanding – basic (in shares)			10,048	6,741
Effect of nonvested phantom units (in shares)			0	0
Weighted-average common units outstanding – diluted (in shares)			10,048	6,741
Common unit - basic (in dollars per share)			$ (12.71)	$ (6.57)
Common unit - diluted (in dollars per share)			$ (12.71)	$ (6.57)

SUPPLEMENTAL CASH FLOW INFORM_3

SUPPLEMENTAL CASH FLOW INFORMATION (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Supplemental cash flow information:
Cash interest paid	$ 89,472	$ 57,655
Cash paid for taxes	149	191
Noncash investing and financing activities:
Capital expenditures in trade accounts payable (period-end accruals)	6,724	5,692
Exercise of ECP Warrants	0	15,542
2022 Preferred Exchange Offer	92,587	0
2021 Preferred Exchange Offer	0	20,654
Series A Preferred Units
Noncash investing and financing activities:
Accretion of Subsidiary Series A Preferred Units	$ 15,544	$ 10,536

UNIT-BASED AND NONCASH COMPEN_3

UNIT-BASED AND NONCASH COMPENSATION - Narrative (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) director $ / shares shares	Dec. 31, 2021 $ / shares shares	Dec. 31, 2020 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average remaining vesting period (in years)	1 year 7 months 13 days
SMLP LTIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for issuance (in shares)	1,000,000
Units remaining available (in shares)	900,000
Unrecognized unit-based compensation | $	$ 6.3
SMLP LTIP | Phantom Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested phantom units granted (in shares)	605,142	333,779	291,691
Units granted (in shares)	509,631	199,241
Granted (in dollars per unit) | $ / shares	$ 17.70	$ 22.33
SMLP LTIP | Phantom Share Units And Associated Distribution Equivalent Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted (in shares)	170,986
Vesting period (in years)	3 years
SMLP LTIP | Phantom Share Units And Associated Distribution Equivalent Rights | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in dollars per unit) | $ / shares	$ 13.58
Vesting period (in years)	2 years
SMLP LTIP | Phantom Share Units And Associated Distribution Equivalent Rights | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in dollars per unit) | $ / shares	$ 20.50
Vesting period (in years)	3 years
SMLP LTIP | Phantom Shares Exchanged For Granted Cash
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted cash exchanged for phantom units (in shares)	299,981
SMLP LTIP | Common units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common units issued (in shares)	38,664
Number of directors | director	6
Grant date fair value (in dollars per share) | $ / shares	$ 14.21

UNIT-BASED AND NONCASH COMPEN_4

UNIT-BASED AND NONCASH COMPENSATION - SMLP Long-Term Incentive Plan (Details) - SMLP LTIP - Phantom Units - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Units
Beginning balance (in shares)	333,779	291,691
Granted (in shares)	509,631	199,241
Vested (in shares)	(229,551)	(143,768)
Forfeited (in shares)	(8,717)	(13,385)
Ending balance (in shares)	605,142	333,779
Weighted-average grant date fair value
Beginning balance (in dollars per unit)	$ 21.78	$ 26.57
Granted (in dollars per unit)	17.70	22.33
Vested (in dollars per unit)	23.61	30.66
Forfeited (in dollars per unit)	22.53	38.85
Ending balance (in dollars per unit)	$ 17.62	$ 21.78

UNIT-BASED AND NONCASH COMPEN_5

UNIT-BASED AND NONCASH COMPENSATION - Schedule of Intrinsic Values (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
SMLP LTIP | Phantom Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of vested LTIP awards	$ 5,420	$ 4,407

UNIT-BASED AND NONCASH COMPEN_6

UNIT-BASED AND NONCASH COMPENSATION - SMP Net Profits Interests (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
SMLP LTIP unit-based compensation	$ 3,778	$ 4,744
SMLP LTIP | General and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
SMLP LTIP unit-based compensation		$ 4,744

LEASES - Narrative (Details)

LEASES - Narrative (Details)	12 Months Ended
	Dec. 31, 2022
Loss Contingencies [Line Items]
Finance leases, term of contract (in years)	3 years
Revolving credit facility
Loss Contingencies [Line Items]
Percentage of operating lease incremental borrowing rate (as a percent)	6.43%
Minimum | Office Space
Loss Contingencies [Line Items]
Operating leases, term of contract (in years)	3 years
Minimum | Equipment
Loss Contingencies [Line Items]
Operating leases, term of contract (in years)	3 years
Maximum | Office Space
Loss Contingencies [Line Items]
Operating leases, term of contract (in years)	10 years
Maximum | Equipment
Loss Contingencies [Line Items]
Operating leases, term of contract (in years)	4 years

LEASES - Schedule of Right of U

LEASES - Schedule of Right of Use Assets and Lease Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
ROU assets
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other noncurrent assets	Other noncurrent assets
Operating	$ 11,633	$ 2,515
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other noncurrent assets	Other noncurrent assets
Finance	$ 1,389	$ 792
Total	$ 13,022	$ 3,307
Lease liabilities, current
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other current liabilities	Other current liabilities
Operating	$ 2,570	$ 1,213
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities	Other current liabilities
Finance	$ 435	$ 167
Total	$ 3,005	$ 1,380
Lease liabilities, noncurrent
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other noncurrent liabilities	Other noncurrent liabilities
Operating	$ 9,672	$ 2,272
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other noncurrent liabilities	Other noncurrent liabilities
Finance	$ 679	$ 122
Total	$ 10,351	$ 2,394

LEASES - Schedule of Lease Cost

LEASES - Schedule of Lease Cost and Other Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Lease cost
Amortization of ROU assets (included in depreciation and amortization)	$ 673	$ 1,026
Interest on lease liabilities (included in interest expense)	18	20
Operating lease cost (included in general and administrative expense)	1,815	1,722
Total lease cost	2,506	2,768
Other information
Operating cash outflows from operating leases	1,732	1,407
Operating cash outflows from finance leases	18	20
Financing cash outflows from finance leases	330	634
ROU assets obtained in exchange for new operating lease liabilities	9,865	0
ROU assets obtained in exchange for new finance lease liabilities	$ 1,298	$ 94
Weighted-average remaining lease term (years) - operating leases	4 years 8 months 12 days	5 years 1 month 6 days
Weighted-average remaining lease term (years) - finance leases	2 years 4 months 24 days	1 year 1 month 6 days
Weighted-average discount rate - operating leases (as a percent)	6%	5%
Weighted-average discount rate - finance leases (as a percent)	3%	4%

LEASES - Lease Expense (Details

LEASES - Lease Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Lease expense	$ 3,162	$ 2,479

LEASES - Future Minimum Lease P

LEASES - Future Minimum Lease Payments Due and Future Minimum Rentals to be Received under Noncancelable Leases (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Operating
2023	$ 4,026
2024	3,650
2025	3,486
2026	2,646
2027	2,280
2028	61
Thereafter	357
Total future minimum lease payments	16,506
Finance
2023	538
2024	489
2025	276
2026	7
2027	0
2028	0
Thereafter	0
Total future minimum lease payments	$ 1,310

SEGMENT INFORMATION - Assets, R

SEGMENT INFORMATION - Assets, Revenues, Depreciation and Amortization, and Capital Expenditures by Reportable Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Total assets	$ 2,559,964	$ 2,522,462
Total revenues	369,594	400,618
Depreciation and amortization	119,993	119,995
Total cash paid for capital expenditures	30,472	25,030
Reportable Segments
Segment Reporting Information [Line Items]
Total assets	2,547,818	2,513,633
Total revenues	368,591	400,578
Depreciation and amortization	118,237	117,331
Total cash paid for capital expenditures	28,535	24,499
Reportable Segments | Northeast
Segment Reporting Information [Line Items]
Total assets	591,091	623,224
Total revenues	54,392	62,567
Depreciation and amortization	17,501	17,054
Total cash paid for capital expenditures	8,743	11,237
Reportable Segments | Rockies
Segment Reporting Information [Line Items]
Total assets	886,629	592,148
Total revenues	143,603	145,087
Depreciation and amortization	30,532	29,513
Total cash paid for capital expenditures	11,903	9,875
Reportable Segments | Permian
Segment Reporting Information [Line Items]
Total assets	298,906	458,988
Total revenues	25,151	40,848
Depreciation and amortization	2,736	5,858
Total cash paid for capital expenditures	1,407	2,042
Reportable Segments | Piceance
Segment Reporting Information [Line Items]
Total assets	475,719	524,218
Total revenues	93,349	105,485
Depreciation and amortization	51,352	48,773
Total cash paid for capital expenditures	6,116	579
Reportable Segments | Barnett
Segment Reporting Information [Line Items]
Total assets	295,473	315,055
Total revenues	52,096	46,591
Depreciation and amortization	16,116	16,133
Total cash paid for capital expenditures	366	766
Corporate and Other
Segment Reporting Information [Line Items]
Total assets	12,146	8,829
Total revenues	1,003	40
Depreciation and amortization	1,756	2,664
Total cash paid for capital expenditures	$ 1,937	$ 531

SEGMENT INFORMATION - Concentra

SEGMENT INFORMATION - Concentration Risk (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Sales Revenue, Net | Customer Concentration Risk | Counterparty A - Piceance
Segment Reporting Information [Line Items]
Concentration risk (as a percent)	13%	12%

SEGMENT INFORMATION - Adjusted

SEGMENT INFORMATION - Adjusted EBITDA by Reportable Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Total of reportable segments' measures of profit	$ 244,586	$ 267,278
Northeast
Segment Reporting Information [Line Items]
Total of reportable segments' measures of profit	77,046	83,287
Rockies
Segment Reporting Information [Line Items]
Total of reportable segments' measures of profit	57,810	64,517
Permian
Segment Reporting Information [Line Items]
Total of reportable segments' measures of profit	18,051	6,614
Piceance
Segment Reporting Information [Line Items]
Total of reportable segments' measures of profit	60,055	76,131
Barnett
Segment Reporting Information [Line Items]
Total of reportable segments' measures of profit	$ 31,624	$ 36,729

SEGMENT INFORMATION - Reconcili

SEGMENT INFORMATION - Reconciliation of Net Income (Loss) to Adjusted EBITDA (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting [Abstract]
Loss before income taxes and equity method investment income	$ (141,277)	$ (28,156)
Add:
Corporate and Other expense	29,118	68,783
Interest expense	102,459	66,156
Gain on early extinguishment of debt	0	3,523
Depreciation and amortization	119,993	119,995
Proportional adjusted EBITDA for equity method investees	45,419	29,022
Adjustments related to capital reimbursement activity	(6,041)	(6,571)
Unit-based and noncash compensation	3,778	4,744
Gain on asset sales, net	(507)	(369)
Long-lived asset impairment	91,644	10,151
Total of reportable segments' measures of profit	$ 244,586	$ 267,278