Middlesex Water (MSEX) 10-K 28 Feb 25 2024 FY Annual report Financial data

Cover

Cover - USD ($)	12 Months Ended
	Dec. 31, 2024	Feb. 26, 2025	Jun. 30, 2024
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Financial Statement Error Correction [Flag]	false
Entity Interactive Data Current	Yes
ICFR Auditor Attestation Flag	true
Amendment Flag	false
Document Period End Date	Dec. 31, 2024
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	FY
Documents Incorporated by Reference [Text Block]	Proxy Statement to be filed in connection with the Registrant’s Annual Meeting of Stockholders to be held on May 20, 2025, which will be filed with the Securities and Exchange Commission within 120 days of the end of our 2024 fiscal year, is incorporated by reference into Part III of this Annual Report on Form 10-K to the extent described herein.
Entity Information [Line Items]
Entity Registrant Name	MIDDLESEX WATER COMPANY
Entity Central Index Key	0000066004
Entity File Number	0-422
Entity Tax Identification Number	22-1114430
Entity Incorporation, State or Country Code	NJ
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Public Float			$ 906,502,416
Entity Contact Personnel [Line Items]
Entity Address, Address Line One	485C Route 1 South
Entity Address, Address Line Two	Suite 400
Entity Address, City or Town	Iselin
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	08830
Entity Phone Fax Numbers [Line Items]
City Area Code	(732)
Local Phone Number	634-1500
Entity Listings [Line Items]
Title of 12(b) Security	Common Stock, No Par Value
Trading Symbol	MSEX
Security Exchange Name	NASDAQ
Entity Common Stock, Shares Outstanding		17,887,454

Audit Information

Audit Information	12 Months Ended
	Dec. 31, 2024
Auditor [Table]
Auditor Name	Baker Tilly US, LLP
Auditor Firm ID	23
Auditor Location	Philadelphia, Pennsylvania
Auditor Opinion [Text Block]	Opinions on the Financial Statements and Internal Control over Financial Reporting We have audited the accompanying consolidated balance sheets and consolidated statements of capital stock and long-term debt of Middlesex Water Company (the "Company") as of December 31, 2024 and 2023, the related consolidated statements of income, common stockholders' equity, and cash flows for each of the three years in the period ended December 31, 2024, and the related notes (collectively referred to as the "consolidated financial statements"). We also have audited the Company’s internal control over financial reporting as of December 31, 2024, based on criteria established in Internal Control – Integrated Framework (2013) In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2024 and 2023, and the results of their operations and their cash flows for each of the three years in the period ended December 31, 2024, in conformity with accounting principles generally accepted in the United States of America. Also in our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2024, based on criteria established in Internal Control – Integrated Framework: (2013)

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Statement [Abstract]
Operating Revenues	$ 191,877	$ 166,274	$ 162,434
Operating Expenses:
Operations and Maintenance	92,363	83,113	79,096
Depreciation	24,430	25,194	23,029
Other Taxes	21,874	18,744	18,208
Total Operating Expenses	138,667	127,051	120,333
Gain on Sale of Subsidiary			5,232
Operating Income	53,210	39,223	47,333
Other Income:
Allowance for Funds Used During Construction	1,254	2,433	2,314
Other Income, net	10,815	4,052	5,389
Total Other Income, net	12,069	6,485	7,703
Interest Charges	14,023	13,143	9,367
Income before Income Taxes	51,256	32,565	45,669
Income Taxes	6,905	1,041	3,240
Net Income	44,351	31,524	42,429
Preferred Stock Dividend Requirements	112	120	120
Earnings Applicable to Common Stock	$ 44,239	$ 31,404	$ 42,309
Earnings per share of Common Stock:
Basic (in Dollars per share)	$ 2.48	$ 1.77	$ 2.4
Diluted (in Dollars per share)	$ 2.47	$ 1.76	$ 2.39
Common Shares Outstanding :
Basic (in Shares)	17,842	17,732	17,597
Diluted (in Shares)	17,946	17,847	17,712

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
UTILITY PLANT: Water Production	$ 314,924	$ 303,791
Transmission and Distribution	855,497	809,862
General	105,167	100,593
Construction Work in Progress	34,209	19,636
TOTAL	1,309,797	1,233,882
Less Accumulated Depreciation	254,425	235,540
UTILITY PLANT - NET	1,055,372	998,342
CURRENT ASSETS: Cash and Cash Equivalents	4,226	2,390
Accounts Receivable, net of allowance for credit losses of $2,695 and $2,137, respectively in 2024 and 2023	18,842	18,172
Litigation Settlement Receivable		69,872
Unbilled Revenues	10,764	9,297
Materials and Supplies (at average cost)	6,719	6,972
Prepayments	2,422	1,833
TOTAL CURRENT ASSETS	42,973	108,536
OTHER ASSETS: Operating Lease Right of Use Asset	2,567	3,185
Regulatory Assets	101,783	90,694
Non-utility Assets - Net	11,760	11,522
Employee Benefit Plans	36,856	21,779
Other	3,863	1,994
TOTAL OTHER ASSETS	156,829	129,174
TOTAL ASSETS	1,255,174	1,236,052
CAPITALIZATION AND LIABILITIES
CAPITALIZATION: Common Stock, No Par Value	248,202	246,764
Retained Earnings	197,061	176,227
TOTAL COMMON STOCKHOLDERS’ EQUITY	445,263	422,991
Preferred Stock	1,635	2,084
Long-term Debt	352,822	358,153
TOTAL CAPITALIZATION	799,720	783,228
CURRENT Current Portion of Long-term Debt	7,711	7,740
LIABILITIES: Notes Payable	23,000	42,750
Accounts Payable	28,050	27,618
Litigation Settlement Payable		6,237
Accrued Taxes	11,976	10,535
Accrued Interest	2,916	3,138
Unearned Revenues and Advanced Service Fees	1,476	1,390
Other	7,759	4,421
TOTAL CURRENT LIABILITIES	82,888	103,829
COMMITMENTS AND CONTINGENT LIABILITIES (Note 4)
OTHER LIABILITIES: Advances for Construction	22,629	21,313
Lease Obligations	2,432	3,063
Accumulated Deferred Income Taxes	101,235	88,736
Regulatory Liabilities	64,557	113,021
Other	344	592
TOTAL OTHER LIABILITIES	191,197	226,725
CONTRIBUTIONS IN AID OF CONSTRUCTION	181,369	122,270
TOTAL CAPITALIZATION AND LIABILITIES	$ 1,255,174	$ 1,236,052

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Accounts receivable, et of allowance for credit losses	$ 2,695	$ 2,137

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income	$ 44,351	$ 31,524	$ 42,429
Net Cash Provided by Operating Activities:
Depreciation and Amortization	28,038	29,442	27,475
Provision for Deferred Income Taxes and Investment Tax Credits	(1,605)	(5,599)	(5,334)
Equity Portion of Allowance for Funds Used During Construction (AFUDC)	(743)	(1,458)	(1,387)
Cash Surrender Value of Life Insurance	(308)	(300)	401
Stock Compensation Expense	1,537	2,214	1,630
Gain on Sale of Subsidiary			(5,232)
Changes in Assets and Liabilities:
Accounts Receivable	(670)	(2,154)	(707)
Unbilled Revenues	(1,467)	(638)	(1,386)
Materials and Supplies	253	(795)	(819)
Prepayments	(589)	791	256
Accounts Payable	2,574	2,771	3,722
Accrued Taxes	1,441	(1,627)	3,541
Accrued Interest	(222)	603	549
Employee Benefit Plans	(3,696)	(1,340)	(4,266)
Unearned Revenue and Advanced Service Fees	86	25	35
Recovered Costs Litigation Settlement	(9,031)
Other Assets and Liabilities	(1,219)	(677)	454
NET CASH PROVIDED BY OPERATING ACTIVITIES	58,730	52,782	61,361
CASH FLOWS FROM INVESTING ACTIVITIES:
Utility Plant Expenditures, Including AFUDC-Debt of $511 in 2024, $975 in 2023 and $927 in 2022	(74,622)	(90,179)	(91,335)
Proceeds from Sale of Subsidiary			3,122
NET CASH USED IN INVESTING ACTIVITIES	(74,622)	(90,179)	(88,213)
CASH FLOWS FROM FINANCING ACTIVITIES:
Redemption of Long-term Debt	(7,646)	(17,463)	(7,423)
Proceeds from Issuance of Long-term Debt	2,296	75,812	2,662
Net Short-term Bank Borrowings	(19,750)	(12,750)	42,500
Proceeds from Litigation Settlement, net	63,635
Deferred Debt Issuance Expense	(54)	(131)	(624)
Common Stock Issuance Expense		(10)	(32)
Payment of Grantee Withholding Taxes in Exchange for Restricted Stock	(1,468)	(619)
Proceeds from Issuance of Common Stock	974	12,115	10,335
Payment of Common Dividends	(23,408)	(22,441)	(20,810)
Payment of Preferred Dividends	(109)	(120)	(120)
Construction Advances and Contributions-Net	3,258	1,566	659
NET CASH PROVIDED BY FINANCING ACTIVITIES	17,728	35,959	27,147
NET CHANGES IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	1,836	(1,438)	295
CASH, CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF PERIOD	2,390	3,828	3,533
CASH, CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD	4,226	2,390	3,828
SUPPLEMENTAL DISCLOSURE OF NON-CASH ACTIVITY:
Utility Plant received as Construction Advances and Contributions	8,968	7,259	6,252
Accrued Payables for Utility Plant	8,109	10,251	7,066
Non-Cash Consideration for Sale of Subsidiary			2,100
Litigation Settlement Receivable	(6,237)	69,872
Litigation Settlement Payable	(6,237)	6,237
Conversion of Preferred Stock Into Common Stock	449
Cash Paid During the Year for:
Interest	14,485	12,762	9,251
Interest Capitalized	511	975	927
Income Taxes	$ 3,169	$ 2,962	$ 3,230

CONSOLIDATED STATEMENTS OF CA_2

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Statement of Cash Flows [Abstract]
Utility Plant Expenditures, Including AFUDC	$ 511	$ 975	$ 927

CONSOLIDATED STATEMENTS OF CAPI

CONSOLIDATED STATEMENTS OF CAPITAL STOCK AND LONG-TERM DEBT - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Common Stock, No Par Value
Shares Authorized Value
Shares Outstanding Value	248,202	246,764
Retained Earnings	197,061	176,227
TOTAL COMMON STOCKHOLDERS’ EQUITY	445,263	422,991
Cumulative Preferred Stock, No Par Value:
Shares Authorized Value
Shares Outstanding Value
Convertible:
TOTAL PREFERRED STOCK	1,635	2,084
Long-term Debt:
SUBTOTAL LONG-TERM DEBT	359,386	364,736
Add: Premium on Issuance of Long-term Debt	6,339	6,529
Less: Unamortized Debt Expense	(5,192)	(5,372)
Less: Current Portion of Long-term Debt	(7,711)	(7,740)
TOTAL LONG-TERM DEBT	352,822	358,153
First Mortgage Bonds
Long-term Debt:
SUBTOTAL LONG-TERM DEBT	274,602	278,374
Amortizing Secured Notes
Long-term Debt:
SUBTOTAL LONG-TERM DEBT	66,889	69,724
State Revolving Trust Notes
Long-term Debt:
SUBTOTAL LONG-TERM DEBT	17,895	16,638
Convertible Preferred Stock $7.00 Series
Convertible:
TOTAL PREFERRED STOCK	556	1,005
Nonredeemable Preferred Stock $7.00 Series
Convertible:
TOTAL PREFERRED STOCK	79	79
Nonredeemable Preferred Stock $4.75 Series
Convertible:
TOTAL PREFERRED STOCK	$ 1,000	$ 1,000

CONSOLIDATED STATEMENTS OF CA_3

CONSOLIDATED STATEMENTS OF CAPITAL STOCK AND LONG-TERM DEBT (Parentheticals) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Shares Authorized	40,000	40,000
Shares Outstanding	17,887	17,821
Shares Authorized (in Dollars)	$ 120	$ 120
Shares Outstanding	16	20
First Mortgage Bonds due 2026-2059
Long term debt maturity period	2026-2059
Amortizing Secured Notes due 2028-2046
Long term debt maturity period	2028-2046
State Revolving Trust Notes due 2025-2047
Long term debt maturity period	2025-2047
Minimum | First Mortgage Bonds due 2026-2059
Interest rate	0%
Minimum | Amortizing Secured Notes due 2028-2046
Interest rate	3.94%
Minimum | State Revolving Trust Notes due 2025-2047
Interest rate	0%
Maximum | First Mortgage Bonds due 2026-2059
Interest rate	5.50%
Maximum | Amortizing Secured Notes due 2028-2046
Interest rate	7.05%
Maximum | State Revolving Trust Notes due 2025-2047
Interest rate	4.03%
Convertible Preferred Stock $7.00 Series
Shares Outstanding	5	10
Nonredeemable Preferred Stock $7.00 Series
Shares Outstanding	1	1
Nonredeemable Preferred Stock $4.75 Series
Shares Outstanding	10	10

CONSOLIDATED STATEMENTS OF COMM

CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Common Stock	Retained Earnings	Total
Balance at Dec. 31, 2021	$ 221,919	$ 145,807	$ 367,726
Balance (in Shares) at Dec. 31, 2021	17,522
Net Income		42,429	42,429
Dividend Reinvestment & Common Stock Purchase Plan	$ 10,335		10,335
Dividend Reinvestment & Common Stock Purchase Plan (in Shares)	114
Restricted Stock Award - Net - Employees	$ 520		520
Restricted Stock Award - Net - Employees (in Shares)	3
Stock Award - Board Of Directors	$ 280		280
Stock Award - Board Of Directors (in Shares)	3
Cash Dividends on Common Stock		(20,810)	(20,810)
Cash Dividends on Preferred Stock		(120)	(120)
Common Stock Issuance Expenses		(32)	(32)
Balance at Dec. 31, 2022	$ 233,054	167,274	400,328
Balance (in Shares) at Dec. 31, 2022	17,642
Net Income		31,524	31,524
Dividend Reinvestment & Common Stock Purchase Plan	$ 12,115		12,115
Dividend Reinvestment & Common Stock Purchase Plan (in Shares)	167
Restricted Stock Award - Net - Employees	$ 1,235		1,235
Restricted Stock Award - Net - Employees (in Shares)	7
Stock Award - Board Of Directors	$ 360		360
Stock Award - Board Of Directors (in Shares)	5
Cash Dividends on Common Stock		(22,441)	(22,441)
Cash Dividends on Preferred Stock		(120)	(120)
Common Stock Issuance Expenses		(10)	(10)
Balance at Dec. 31, 2023	$ 246,764	176,227	422,991
Balance (in Shares) at Dec. 31, 2023	17,821
Net Income		44,351	44,351
Dividend Reinvestment & Common Stock Purchase Plan	$ 974		974
Dividend Reinvestment & Common Stock Purchase Plan (in Shares)	17
Restricted Stock Award - Net - Employees	$ (383)		(383)
Restricted Stock Award - Net - Employees (in Shares)	(10)
Stock Award - Board Of Directors	$ 398		398
Stock Award - Board Of Directors (in Shares)	8
Cash Dividends on Common Stock		(23,408)	(23,408)
Cash Dividends on Preferred Stock		(109)	(109)
Conversion of $7 Preferred Stock to Common Stock	$ 449		449
Conversion of $7 Preferred Stock to Common Stock (in Shares)	51
Balance at Dec. 31, 2024	$ 248,202	$ 197,061	$ 445,263
Balance (in Shares) at Dec. 31, 2024	17,887

CONSOLIDATED STATEMENTS OF CO_2

CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDERS' EQUITY (Parentheticals) - $ / shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Statement of Stockholders' Equity [Abstract]
Cash dividends, per share	$ 1.315	$ 1.2625	$ 1.1825
Preferred Stock to Common Stock	$ 7	$ 7	$ 7

Organization, Summary of Signif

Organization, Summary of Significant Accounting Policies and Recent Developments	12 Months Ended
	Dec. 31, 2024
Organization, Summary of Significant Accounting Policies and Recent Developments [Abstract]
Organization, Summary of Significant Accounting Policies and Recent Developments	Note 1 – Organization, Summary of Significant Accounting Policies and Recent Developments (a) Organization Middlesex has operated as a water utility in New Jersey since 1897 and in Delaware, through our wholly-owned subsidiary, Tidewater, since 1992. We are in the business of providing an essential water utility service for domestic, commercial, municipal, industrial and fire protection purposes. We also operate New Jersey municipal water, wastewater and storm water systems under contract and provide unregulated water and wastewater services in New Jersey and Delaware through our subsidiaries. Our rates charged to customers for water and wastewater services, the quality of services we provide and certain other matters are regulated in New Jersey and Delaware by the New Jersey Board of Public Utilities (NJBPU) and the Delaware Public Service Commission (DEPSC), respectively. Our USA, USA-PA and White Marsh subsidiaries are not regulated utilities. (b) Principles of Consolidation – (c) System of Accounts – (d) Regulatory Accounting Regulated Operations In accordance with ASC 980, Regulated Operations Rate and Regulatory Matters (e) Retirement Benefit Plans The Company’s costs for providing retirement benefits are dependent upon numerous factors, including actual plan experience and assumptions of future experience. Retirement benefit plan obligations and expense are determined based on investment performance, discount rates and various other demographic factors related to the population participating in the Company’s retirement benefit plans, all of which can change significantly in future years. For more information on the Company’s Retirement Benefit Plans, see Note 7 – Employee Benefit Plans (f) Utility Plant – (g) Depreciation – Source of Supply 1.15% - 3.44% Transmission and Distribution (T&D): Pumping 2.00% - 5.39% T&D – Mains 1.10% - 3.13% Water Treatment 1.65% - 7.09% T&D – Services 2.12% - 3.16% General Plant 2.08% - 17.84% T&D – Other 1.61% - 4.63% Wastewater Collection 1.42% - 1.81% Non-regulated fixed assets consist primarily of office buildings, furniture and fixtures, and transportation equipment. These assets are recorded at original cost and depreciation is calculated based on the estimated useful lives, ranging from 3 to 42 years. (i) Advances for Construction – CIAC In accordance with regulatory requirements, Advances for Construction and CIAC are not depreciated. In addition, these amounts reduce the investment base for purposes of setting rates. (j) Allowance for Funds Used During Construction (AFUDC) 2024 2023 2022 Middlesex 6.64% 6.35% 6.35% Tidewater 7.92% 7.92% 7.92% (k) Accounts Receivable (l) Revenues The Company’s regulated revenue results from tariff-based water and wastewater utility services to residential, industrial, commercial, fire-protection and wholesale customers. Residential customers are billed quarterly while most industrial, commercial, fire-protection and wholesale customers are billed monthly. Payments by customers are due between 15 to 30 days after the invoice date. Revenue is recognized as the water and wastewater services are delivered to customers which includes an accrual of unbilled revenues estimated from the last meter reading date to the end of the accounting period utilizing factors such as historical customer data and regional weather indicators. Unearned Revenues and Advance Service Fees include fixed service charge billings in advance to Tidewater customers recognized as service is provided to the customer. Non-regulated service contract revenues consist of base service fees as well as fees for additional billable services provided to customers. Fees are billed monthly and are due within 30 days after the invoice date. The Company considers the amounts billed to represent the value of these services provided to customers. These contracts expire at various times through 2032 and contain remaining performance obligations for which the Company expects to recognize revenue in the future. These contracts also contain customary termination provisions. Substantially all of the amounts included in operating revenues and accounts receivable are from contracts with customers. The Company’s contracts do not contain any significant financing components. The Company’s operating revenues are comprised of the following: (In Thousands) Years Ended December 31, 2024 2023 2022 Regulated Tariff Sales Residential $ 97,802 $ 86,581 $ 84,950 Commercial 31,833 23,945 22,689 Industrial 13,842 11,586 11,152 Fire Protection 14,188 12,582 12,726 Wholesale 21,003 19,117 18,769 Non-Regulated Contract Operations 13,085 12,320 12,006 Total Revenue from Contracts with Customers $ 191,753 $ 166,131 $ 162,292 Other Regulated Revenues 691 806 831 Other Non-Regulated Revenues 467 453 440 Inter-segment Elimination (1,034 ) (1,116 ) (1,129 ) Total Revenue $ 191,877 $ 166,274 $ 162,434 (m) Unamortized Debt Expense and Premiums on Long-Term Debt (n) Income Taxes Income Taxes (o) Cash and Cash Equivalents (p) Use of Estimates (q) Recent Accounting Pronouncements Standard Description Date of Adoption Application Effect on the Accounting Standards Update (“ASU”) 2023-07 “Improvements to Reportable Segment Disclosures” The ASU requires disclosure of significant segment expenses, extends certain annual disclosures to interim periods, and additional qualitative disclosures regarding the chief operating decision maker. The ASU is effective for the Company beginning with its annual financial statements for the year ended December 31, 2024. Retrospective The Company adopted ASU 2023-07, including a recast of 2023 and 2022 information, by including additional required disclosures within the Notes to the Consolidated Financial Statements -see Note 8- Reportable Segments ASU 2023-09 “Improvements to Income Tax Disclosures” The ASU amends certain income tax disclosure requirements, including adding requirements to present the reconciliation of income tax expense computed at the statutory rate to actual income tax expense using both percentages and amounts and providing a disaggregation of income taxes paid. Further, certain disclosures are eliminated, including the current requirement to disclose information on changes in unrecognized tax benefits in the next 12 months. The ASU is effective for the Company beginning with its annual financial statements for the year ending December 31, 2025. Early adoption is permitted. Prospective, with retrospective application also permitted. The Company is currently evaluating the requirements of ASU 2023-09. ASU 2024-03 “Disaggregation of Income Statement Expenses” The ASU enhances disclosures related to income statement expenses to further disaggregate expenses in the footnotes to the financial statements. The standard requires disaggregation of any relevant expense caption presented on the face of the income statement that contains the following expense categories: purchases of inventory, employee compensation, depreciation, intangible asset amortization, and depletion. Further, the standard requires disclosure of the total amount and the entity’s definition of selling expenses. The ASU is effective for the Company beginning with its annual financial statements for the year ended December 31, 2027. Prospective, with retrospective application also permitted. The Company is currently evaluating the requirements of ASU 2024-03. (r) Reclassifications –

Rate and Regulatory Matters

Rate and Regulatory Matters	12 Months Ended
	Dec. 31, 2024
Rate and Regulatory Matters [Abstract]
Rate and Regulatory Matters	Note 2 - Rate and Regulatory Matters Rate Matters Middlesex The Middlesex Lead Service Line Replacement (LSLR) Plan, which was approved by the NJBPU in January 2024, has commenced and Middlesex is currently recovering $1.2 million of costs for replacing customer-owned lead service lines incurred through June 2024, which are being recovered between September 2024 and February 2025. Costs of $0.6 million for replacing customer-owned lead service lines incurred between July 2024 through December 2024 will be recovered beginning in March 2025 through August 2025. The LSLR surcharge is required to be reset every six months over the life of the LSLR Plan. Cost recovery for replacing Company-owned lead service lines are recoverable through traditional rate making in connection with general rate case filings. In October 2023, the NJBPU approved Middlesex’s petition for a Distribution System Improvement Charge (DSIC) Foundation Filing, which is a prerequisite to implementing a DSIC rate that allows water utilities to recover investments in, and generate a return on, qualifying capital improvements to their water distribution system made between base rate proceedings. Middlesex is authorized to recover DSIC revenues up to five percent (5%) of total revenues established in Middlesex’s 2021 base rate proceeding, or approximately $5.5 million. Semi-annually, beginning in April 2024, the Company must file for a change in its DSIC rate seeking recovery for DSIC-eligible investments made during the period. DSIC rates remain in effect until Middlesex’s next base rate case increase subsequent to the March 1, 2024 increase. Under the terms of the Foundational Filing, the Company is required to file a base rate petition before November 2026. In May 2024, the NJBPU approved a DSIC rate, effective May 26, 2024, that is expected to result in $0.5 million of annual revenue. In November 2024, the NJBPU approved a DSIC rate, effective November 26, 2024, that is expected to result in an additional $0.6 million of annual revenue. Middlesex expects to file for an additional DSIC rate increase in April 2025. In February 2025, the NJBPU approved Middlesex’s petition to reset its Purchased Water Adjustment Clause (PWAC) tariff rate to recover additional annual costs of $0.5 million, primarily for the purchase of treated water from a non-affiliated water utility regulated by the NJBPU. A PWAC is a rate mechanism that allows for the recovery of increased purchased water costs between base rate case filings. The PWAC is reset to zero once those increased costs are included in base rates. The new PWAC rate will be effective March 1, 2025. Tidewater – In September 2024, the DEPSC approved Tidewater’s petition to recover up to $2.1 million of costs associated with Tidewater’s obligation to identify and inventory lead service lines throughout Tidewater’s service area, as required by federal law and Delaware regulations. Recovery of these costs began February 1, 2025 and is expected to continue through January 2028. Through December 31, 2024, Tidewater has spent $1.8 million, which is included in Regulatory Assets. Tidewater Acquisition of the Water Utility Assets of the Town of Ocean View, Delaware – Southern Shores - Twin Lakes – Regulatory Matters We have recorded certain costs as regulatory assets because we expect full recovery of, or are currently recovering, these costs in the rates we charge customers. These deferred costs have been excluded from rate base and, therefore, we are not earning a return on the unamortized balances. We record regulatory liabilities for amounts expected to be refunded to customers in the rate making process. These items are detailed as follows: (In Thousands) December 31, Regulatory Assets 2024 2023 Income Taxes (a) $ 89,825 $ 84,419 Other (b) 11,958 6,275 Total $ 101,783 $ 90,694 Regulatory Liabilities Income Taxes (c) $ 27,380 $ 28,188 Cost of Removal (d) 20,595 19,727 Employee Benefit Plans (e) 9,435 1,471 Lawsuit Settlement (f) 5,334 63,635 New Jersey Revenue Taxes (g) 1,813 — Total $ 64,557 $ 113,021 (a) The recovery period for income taxes is dependent upon when the temporary differences between the tax and book treatment of various items reverse. (b) Other primarily includes deferred costs for rate cases and tank painting. (c) The 2017 Tax Act reduced the statutory corporate federal income tax rate from 35% to 21%. The tariff rates charged to customers effective prior to 2018 in the Company’s regulated companies include recovery of income taxes at the statutory rate in effect at the time those rates were approved by the respective state public utility commissions. The Company has recorded regulatory liabilities for excess income taxes collected through rates due to the lower income tax rate under the 2017 Tax Act. These regulatory liabilities are overwhelmingly related to utility plant depreciation deduction timing differences, which are subject to Internal Revenue Service (IRS) normalization rules. The IRS rules limit how quickly the excess taxes attributable to accelerated taxes can be returned to customers. The current base rates for Middlesex and Pinelands customers became effective after 2017 and reflect the impact of the 2017 Tax Act. (d) The Company uses composite depreciation rates for its regulated utility assets, which is currently an acceptable method under GAAP and is widely used in the utility industry. Historically, under the composite depreciation method, the anticipated costs of removing assets upon retirement are provided for over the life of those assets as a component of depreciation expense. The Company recovers certain asset retirement costs through rates charged to customers as an approved component of depreciation expense. (e) Retirement benefits include pension and other retirement benefits that have been recorded on the Consolidated Balance Sheet in accordance with the guidance provided in ASC 715, Compensation – Retirement Benefits (f) The net proceeds available to Middlesex from the 3M Settlement Agreement were recorded as a regulatory liability and are being used for future related operating and maintenance costs. (g) Revenue related taxes paid by the Company's New Jersey Regulated subsidiaries, and reflected in those subsidiaries current base rates, were above enacted rates and will be refunded back to customers in a future rate proceeding.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2024
Income Taxes [Abstract]
Income Taxes	Note 3 – Income Taxes Income tax expense (benefit) differs from the amount computed by applying the statutory rate on book income subject to tax for the following reasons: (In Thousands) Years Ended December 31, 2024 2023 2022 Income Tax at Statutory Rate $ 10,764 $ 6,839 $ 9,590 Tax Effect of: Utility Plant Related (659 ) (1,495 ) (1,106 ) Tangible Property Repairs (4,535 ) (5,475 ) (6,767 ) State Income Taxes – Net 1,270 1,117 1,296 Other 65 55 227 Total Income Tax Expense $ 6,905 $ 1,041 $ 3,240 Income tax expense (benefit) is comprised of the following: (In Thousands) Years Ended December 31, 2024 2023 2022 Current: Federal $ 1,554 $ 2,952 $ 425 State 1,126 1,066 1,381 Deferred: Federal 3,802 (3,261 ) 1,242 State 482 348 260 Investment Tax Credits (59 ) (64 ) (68 ) Total Income Tax Expense $ 6,905 $ 1,041 $ 3,240 As part of Middlesex’s March 2018 general rate case settlement with the NJBPU, Middlesex received approval for regulatory accounting treatment of income tax benefits associated with the adoption of tangible property regulations issued by the IRS (fully amortized as of March 31, 2022) as well as prospective recognition of the income tax benefits for the immediate deduction of repair costs on tangible property. This results in significant reductions in the Company’s effective income tax rate, current income tax expense and deferred income tax expense (benefit). Deferred income taxes reflect the net tax effect of temporary differences between the carrying amounts of assets and liabilities for financial purposes and the amounts used for income tax purposes. The components of the net deferred tax liability are as follows: (In Thousands) December 31, 2024 2023 Utility Plant Related $ 95,877 $ 84,330 Customer Advances (3,525 ) (3,546 ) Employee Benefits 7,888 7,100 Investment Tax Credits 181 240 Other 814 612 Total Accumulated Deferred Income Taxes $ 101,235 $ 88,736 The determination of our provision for income taxes requires the use of estimates and the interpretation and application of tax laws. Judgment is required in assessing the deductibility and recoverability of certain tax benefits. We use the asset and liability method to determine and record deferred tax assets and liabilities, representing future tax benefits and taxes payable, which result from the differences in basis recorded in GAAP financial statements and amounts recorded in the income tax returns. The deferred tax assets and liabilities are recorded utilizing the statutorily enacted tax rates expected to be in effect at the time the assets are realized and/or the liabilities settled. An offsetting valuation allowance is recorded when it is more likely than not that some or all of the deferred income tax assets won’t be realized. Any significant changes to the estimates and judgments with respect to the interpretations, timing or deductibility could result in a material change to earnings and cash flows. Occasionally, federal and state taxing authorities determine that it is necessary to make certain changes to the income tax laws. These changes may include but are not limited to changes in the tax rates and/or the treatment of certain items of income or expense. Accounting guidance requires that the Company reflect the effect of changes in tax laws or tax rates at the date of enactment. Additionally, the Company is required to re-measure its deferred tax assets and liabilities as of the date of enactment. For non-regulated entities, the effects of changes in tax laws or tax rates are required to be included in income from continuing operations for the period that includes the enactment date. For regulated entities, if as the result of an action by a regulator it is probable that the future increase or decrease in taxes payable for items such as changes in tax laws or rates will be recovered from or returned to customers through future rates, an asset or liability shall be recognized for that probable increase or decrease in future revenue. Accounting guidance also requires that regulatory liabilities and/or assets be considered a temporary difference for which a related deferred tax asset and/or liability shall be recognized. Accounting guidance requires that we establish reserves for uncertain tax positions, if any, when it is more likely than not that the positions will not be sustained when challenged by taxing authorities. Any changes to the estimates and judgments with respect to the interpretations, timing or deductibility could result in a change to earnings and cash flows. Interest and penalties related to unrecognized tax benefits, if any, are recognized within interest charges and other expense, respectively.

Commitments and Contingent Liab

Commitments and Contingent Liabilities	12 Months Ended
	Dec. 31, 2024
Commitments and Contingent Liabilities [Abstract]
Commitments and Contingent Liabilities	Note 4 - Commitments and Contingent Liabilities Water Supply Middlesex also has an agreement with a non-affiliated NJBPU-regulated water utility for the purchase of treated water. This agreement, which expires February 27, 2026, provides for the minimum purchase of 3.0 mgd of treated water with provisions for additional purchases if needed. Tidewater contracts with the City of Dover, Delaware to purchase treated water of up to 75.0 million gallons annually. Purchased water costs are shown below: (In Millions) Years Ended December 31, 2024 2023 2022 Untreated $ 3.5 $ 3.2 $ 3.2 Treated 4.0 5.3 3.9 Total Costs $ 7.5 $ 8.5 $ 7.1 Leases - The Company has entered into an operating lease of office space for administrative purposes, expiring in December 2029. The Company has not entered into any finance leases. The exercise of a lease renewal option for the Company’s administrative offices is solely at the discretion of the Company. The right-of-use (ROU) asset recorded represents the Company’s right to use an underlying asset for the lease term and lease liability represents the Company’s obligation to make lease payments arising from the lease. Lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. The Company’s operating lease does not provide an implicit discount rate and as such the Company used an estimated incremental borrowing rate (4.03%) based on the information available at commencement date in determining the present value of lease payments. Given the impacts of accounting for regulated operations, and the resulting recognition of expense at the amounts recovered in customer rates, expenditures for operating leases are consistent with lease expense and was $0.8 million for each of the years ended December 31, 2024, 2023 and 2022. Information related to operating lease ROU assets is as follows: (In Millions) December 31, 2024 2023 ROU Asset at Lease Inception $ 7.3 $ 7.3 Accumulated Amortization (4.7 ) (4.1 ) Current ROU Asset $ 2.6 $ 3.2 The Company’s future minimum operating lease (In Millions) December 31, 2024 2025 $ 0.8 2026 0.8 2027 0.9 2028 0.9 2029 0.9 Total Lease Payments $ 4.3 Imputed Interest (1.3 ) Present Value of Lease Payments 3.0 Less Current Portion* (0.6 ) Non-Current Lease Liability $ 2.4 *Included in Other Current Liabilities Construction Contingencies Change in Control Agreements

Short-Term Borrowings

Short-Term Borrowings	12 Months Ended
	Dec. 31, 2024
Short-Term Borrowings [Abstract]
Short-term Borrowings	Note 5 – Short-term Borrowings Information regarding the Company’s short-term borrowings for the years ended December 31, 2024 and 2023 is summarized below: ($ In Millions) 2024 2023 Average Amount Outstanding $ 38.7 $ 35.7 Weighted Average Interest Rate 6.33% 6.13% Notes Payable at Year-End $ 23.0 $ 42.8 Weighted Average Interest Rate at Year-End 5.63% 6.50% The Company maintains bank lines of credit aggregating $140.0 million. (In Millions) As of December 31, 2024 Line of Credit Outstanding Available Maximum Credit Type Expiration Date Bank of America $ — $ 60.0 $ 60.0 Uncommitted January 23, 2026 PNC Bank 23.0 45.0 68.0 Committed January 31, 2027 CoBank, ACB (CoBank) — 12.0 12.0 Committed May 20, 2026 $ 23.0 $ 117.0 $ 140.0 The maturity dates for the Notes Payable as of December 31, 2024 are extendable at the discretion of the Company. The interest rates are set for borrowings under the Bank of America and PNC Bank lines of credit using the Secured Overnight Financing Rate (SOFR) and then adding a specific financial institution credit spread. The interest rate for borrowings under the CoBank line of credit are set weekly using CoBank’s internal cost of funds index that is similar to the SOFR and adding a credit spread. There is no requirement for a compensating balance under any of the established lines of credit.

Capitalization

Capitalization	12 Months Ended
	Dec. 31, 2024
Capitalization [Abstract]
Capitalization	Note 6 - Capitalization All the transactions discussed below related to the issuance of securities were approved by either the NJBPU or DEPSC, except where otherwise noted. Common Stock The Company issues shares of its common stock in connection with its Middlesex Water Company Investment Plan (the Investment Plan), a direct share purchase and dividend reinvestment plan for the Company’s common stock. The Company raised approximately $1.0 million under the Investment Plan during 2024. Currently, 0.7 million shares remain registered with the United States Securities and Exchange Commission and available for issuance to participants under the Investment Plan. In April 2023, Middlesex received approval from the NJBPU to issue and sell up to 1.0 million shares of its common stock, without par value, through December 31, 2025. Sales of additional shares of common stock are part of the Company’s comprehensive financing plan to fund its multi-year utility plant infrastructure investment program. As described below in “Long-term Debt”, the NJBPU also approved the debt funding component of the financing plan. The Company issues common shares under a restricted stock plan for certain management employees, which is described in Note 7 – Employee Benefit Plans The Company maintains a stock plan for its independent Directors as a component of outside members of the Board of Directors compensation. For the years ended December 31, 2024, 2023 and 2022, 7,570, 4,608 and 2,664 shares, respectively, of Middlesex common stock were granted and issued to the Company’s independent Directors under the plan. The maximum number of shares authorized for grant under the plan is 100,000, of which 34,283 shares remain available for future awards. In the event dividends on the preferred stock are in arrears, no dividends may be declared or paid on the common stock of the Company. Preferred Stock At December 31, 2024 and 2023, there were 120,000 shares of preferred stock authorized and less than 16,000 shares of preferred stock outstanding. There were no The Company may not pay any dividends on its common stock unless full cumulative dividends to the preceding dividend date for all outstanding shares of preferred stock have been paid or set aside for payment. If four or more quarterly dividends are in arrears, the preferred shareholders, as a class, are entitled to elect two members to the Board of Directors in addition to Directors elected by holders of the common stock. In addition, if Middlesex were to liquidate, holders of preferred stock would be paid back the stated value of their preferred shares before any distributions could be made to common stockholders. The conversion feature of the no par $7.00 Series Cumulative and Convertible Preferred Stock allows the security holders to convert one convertible preferred share for twelve shares of the Company's common stock. In 2024, 4,275 shares of the Company’s no par $7.00 Series Cumulative and Convertible Preferred Stock were converted into 51,300 shares (approximately $0.4 million) of the Company’s common stock. In addition, the Company may redeem up to 10% of the outstanding convertible stock in any calendar year at a price equal to the fair value of twelve shares of the Company's common stock for each share of convertible stock redeemed. Long-term Debt Subject to regulatory approval, the Company periodically issues long-term debt to fund its investments in utility plant. To the extent possible and fiscally prudent, the Company finances qualifying capital projects under State Revolving Fund (SRF) loan programs in New Jersey and Delaware. These government programs provide financing at interest rates typically below rates available in the broader financial markets. Middlesex has received approval from the NJBPU to borrow up to $300.0 million from the New Jersey SRF Program, the New Jersey Economic Development Authority, private placement and other financial institutions as needed through December 31, 2025. The Company expects to issue debt securities in a series of one or more transaction offerings over a multi-year period to help fund Middlesex’s multi-year capital construction program. In September 2024, Tidewater closed on a $2.2 million Delaware SRF loan with a 0.0% interest rate with an expected maturity date in 2044. This loan is for costs associated with Tidewater’s obligation, as required by federal law and Delaware regulations, to identify and inventory lead service lines throughout Tidewater’s service area. Tidewater has drawn down $1.7 million as of December 31, 2024. In May 2024, Tidewater closed on four DEPSC-approved Delaware SRF loans totaling $5.6 million, all at interest rates of 2.0% with expected maturity dates in 2044. These loans are for the construction, relocation, improvement, and/or interconnection of transmission mains and construction of a water treatment facility. Tidewater has drawn down less than $0.1 million on these loans as of December 31, 2024. Each project has its own construction timetable with the last spending set to occur in 2026. Separately, Tidewater has two active construction projects funded by prior year Delaware SRF loans totaling $8.3 million with remaining availability of funds for borrowing. These loans are for the construction of a one million gallon elevated storage tank and construction, relocation, improvement, and interconnection of transmission mains. Tidewater has drawn a total of $4.9 million through December 31, 2024 and expects that the requisitions will continue through the second quarter of 2025. In July 2023, Pinelands Water and Pinelands Wastewater closed on $3.9 million and $3.6 million CoBank amortizing mortgage type loans, respectively, with an interest rate of 6.17% and a final maturity date of 2043 for each loan. Proceeds were used to pay off outstanding intercompany loans with Middlesex and for ongoing capital projects. In May 2023, Tidewater closed on a $20.0 million loan from CoBank with an interest rate of 5.71% and a 2033 maturity date and fully drew all funds by June 30, 2023. Proceeds from the loan were used to pay off Tidewater’s outstanding balances under its bank lines of credit and for other general corporate purposes. In April 2023, Tidewater closed on two DEPSC-approved Delaware SRF loans totaling $6.9 million, all at interest rates of 2.0% with maturity dates in 2043 and 2044. These loans are for the construction, relocation, improvement, and/or interconnection of transmission mains. Tidewater has fully drawn on these loans. In March 2023, Middlesex closed on a $40.0 million, 5.24% private placement of First Mortgage Bonds (FMBs) with a 2043 maturity date designated as Series 2023A. Proceeds were used to reduce the Company’s outstanding balances under its bank lines of credit. In May 2022, Middlesex repaid its two outstanding New Jersey Infrastructure Bank (NJIB) construction loans by issuing FMBs to the NJIB under two loan agreements. The total amount of FMBs issued is $52.2 million and designated as Series 2022A ($16.2 million) and Series 2022B ($36.0 million). The interest rate on the Series 2022A bond is zero and the interest rate on the Series 2022B bond ranges between 2.7% and 3.0%. The final maturity date for both FMBs is August 1, 2056, with scheduled debt service payments over the life of these loans. The aggregate annual principal repayment obligations as of December 31, 2024 for all long-term debt over the next five years and thereafter are shown below: Year (In Millions) 2025 $ 7.7 2026 7.5 2027 7.3 2028 7.0 2029 6.5 Thereafter 323.4 The weighted average interest rate on all long-term debt at December 31, 2024 and 2023 was 3.64% and 3.65%, respectively. Substantially all of the utility plant of the Company is subject to the lien of its mortgage, which includes debt service and capital ratio covenants. The Company is in compliance with all of its mortgage covenants and restrictions. Earnings Per Share The following table presents the calculation of basic and diluted earnings per share (EPS) of common stock for the years ended December 31, 2024, 2023 and 2022. Basic EPS is computed on the basis of the weighted average number of shares outstanding. Diluted EPS assumes the conversion of the Convertible Preferred Stock $7.00 Series. (In Thousands, Except Per Share Amounts) 2024 2023 2022 Basic: Income Shares Income Shares Income Shares Net Income $ 44,351 17,842 $ 31,524 17,732 $ 42,429 17,597 Preferred Dividend (112 ) (120 ) (120 ) Earnings Applicable to Common Stock $ 44,239 17,842 $ 31,404 17,732 $ 42,309 17,597 Basic EPS $ 2.48 $ 1.77 $ 2.40 Diluted: Earnings Applicable to Common Stock $ 44,239 17,842 $ 31,404 17,732 $ 42,309 17,597 Convertible Preferred $7.00 Series Dividend 46 104 67 115 67 115 Adjusted Earnings Applicable to Common Stock $ 44,285 17,946 $ 31,471 17,847 $ 42,376 17,712 Diluted EPS $ 2.47 $ 1.76 $ 2.39 Fair Value of Financial Instruments The following methods and assumptions were used by the Company in estimating its fair value disclosure for financial instruments for which it is practicable to estimate that value. The carrying amounts reflected in the consolidated balance sheets for cash and cash equivalents, accounts receivable, accounts payable and notes payable approximate their respective fair values due to the short-term maturities of these instruments. The fair value of FMBs and SRF Bonds (collectively, the Bonds) issued by Middlesex is based on quoted market prices for similar issues. Under the fair value hierarchy, the fair value of cash and cash equivalents is classified as a Level 1 measurement and the fair value of notes payable and the Bonds in the table below are classified as Level 2 measurements. The carrying amount and fair value of the Bonds were as follows: (In Thousands) At December 31, 2024 2023 Carrying Fair Carrying Fair Amount Value Amount Value FMBs $ 129,602 $ 125,067 $ 133,374 $ 131,745 It was not practicable to estimate the fair value on our outstanding long-term debt for which there is no quoted market price and there is not an active trading market. For details, including carrying value, interest rate and due date on these series of long-term debt, please refer to those series of long-term debt titled “Amortizing Secured Notes” and “State Revolving Trust Notes” on the Consolidated Statements of Capital Stock and Long-Term Debt. The carrying amount of these instruments was $229.8 million and $231.3 million at December 31, 2024 and 2023, respectively. Advances for construction have carrying amounts of $22.6 million and $21.3 million at December 31, 2024 and 2023, respectively. Their relative fair values cannot be accurately estimated since future refund payments depend on several variables, including new customer connections, customer consumption levels and future rate increases.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2024
Employee Benefit Plans [Abstract]
Employee Benefit Plans	Note 7 - Employee Benefit Plans Pension Benefits The Company’s Pension Plan covers all active employees hired prior to April 1, 2007. Employees hired after March 31, 2007 are not eligible to participate in this plan, but can participate in a defined contribution profit sharing plan that provides an annual contribution at the discretion of the Company, based upon a percentage of the participants’ annual paid compensation. In order to be eligible for contribution, the eligible employee must be employed by the Company on December 31 st Other Benefits The Company’s Other Benefits Plan covers substantially all of its current retired employees. Employees hired after March 31, 2007 are not eligible to participate in this plan. Coverage includes healthcare and life insurance. Regulatory Treatment of Over/Underfunded Retirement Obligations Because the Company is subject to rate regulation in the states in which it operates, it is required to maintain its accounts in accordance with the regulatory authority’s rules and guidelines, which may differ from other authoritative accounting pronouncements. In those instances, the Company follows the guidance of ASC 980, Regulated Operations Regulated Operations Compensation – Retirement Benefits The Company uses a December 31 measurement date for all of its employee benefit plans. The tables below set forth information relating to the Company’s Pension Plan and Other Benefits Plan for 2024 and 2023. (In Thousands) Pension Plan Other Benefits Plan Years Ended December 31, 2024 2023 2024 2023 Change in Projected Benefit Obligation: Beginning Balance $ 91,853 $ 87,788 $ 28,000 $ 32,909 Service Cost 1,270 1,551 320 391 Interest Cost 4,280 4,270 1,313 1,608 Actuarial (Gain) Loss (5,478 ) 1,966 (486 ) (5,968 ) Benefits Paid (4,424 ) (3,722 ) (946 ) (940 ) Ending Balance $ 87,501 $ 91,853 $ 28,201 $ 28,000 (In Thousands) Pension Plan Other Benefits Plan Years Ended December 31, 2024 2023 2024 2023 Change in Fair Value of Plan Assets: Beginning Balance $ 92,346 $ 84,828 $ 48,352 $ 44,029 Actual Return on Plan Assets 7,976 10,840 4,675 4,323 Employer Contributions 2,750 400 946 940 Benefits Paid (4,424 ) (3,722 ) (946 ) (940 ) Ending Balance $ 98,648 $ 92,346 $ 53,027 $ 48,352 Funded Status $ 11,147 $ 494 $ 24,826 $ 20,352 (In Thousands) Pension Plan Other Benefits Plan As of December 31, 2024 2023 2024 2023 Amounts Recognized in the Consolidated Balance Sheets consist of: Current Liability $ 883 $ 933 $ — $ — Noncurrent Asset (12,030 ) (1,427 ) (24,826 ) (20,352 ) Net Asset Recognized $ (11,147 ) $ (494 ) $ (24,826 ) $ (20,352 ) (InThousands) Pension Plan Other Benefits Plan Years Ended December 31, 2024 2023 2022 2024 2023 2022 Components of Net Periodic Benefit Cost Service Cost $ 1,270 $ 1,551 $ 2,362 $ 320 $ 391 $ 799 Interest Cost 4,280 4,270 3,042 1,313 1,608 1,325 Expected Return on Plan Assets (6,322 ) (5,865 ) (7,041 ) (3,384 ) (3,082 ) (3,547 ) Amortization of Net Actuarial Loss (Gain) 153 658 1,674 (1,098 ) (191 ) — Net Periodic Benefit Cost* $ (619 ) $ 614 $ 37 $ (2,849 ) $ (1,274 ) $ (1,423 ) * Amounts that are expected to be amortized from Regulatory Assets into Net Periodic Benefit Cost in 2025 are as follows: (In Thousands) Pension Other Actuarial Loss (Gain) $ 50 $ (1,127 ) The discount rate and compensation increase rate for determining our postretirement benefit plans’ benefit obligations and costs as of and for the years ended December 31, 2024, 2023 and 2022, respectively, are as follows: Pension Plan Other Benefits Plan 2024 2023 2022 2024 2023 2022 Weighted Average Assumptions: Expected Return on Plan Assets 7.00% 7.00% 7.00% 7.00% 7.00% 7.00% Discount Rate for: Benefit Obligation 5.47% 4.79% 4.98% 5.49% 4.79% 4.98% Benefit Cost 4.79% 4.98% 2.72% 4.79% 4.98% 2.72% Compensation Increase for: Benefit Obligation 3.00% 3.00% 3.00% 3.00% 3.00% 3.00% Benefit Cost 3.00% 3.00% 3.00% 3.00% 3.00% 3.00% The compensation increase assumption for the Other Benefits Plan is attributable to life insurance provided to qualifying employees upon their retirement. The insurance coverage will be determined based on the employee’s base compensation as of their retirement date. The Company utilizes the Society of Actuaries’ mortality table (Pri-2012) (Mortality Improvement Scale MP2021). For the 2024 valuation, costs and obligations for our Other Benefits Plan assumed a 8.0% annual rate of increase in the per capita cost of covered healthcare benefits in 2024 with the annual rate of increase declining 0.15% per year for 2025-2044, resulting in an annual rate of increase in the per capita cost of covered healthcare benefits of 5.0% by year 2045. A one-percentage point change in assumed healthcare cost trend rates would have the following effects on the Other Benefits Plan: (In Thousands) 1 Percentage Point Increase Decrease Effect on Current Year Service and Interest Costs $ 228 $ (184 ) Effect on Projected Benefit Obligation $ 3,434 $ (2,824 ) The following benefit payments, which reflect expected future service, are expected to be paid: (In Thousands) Year Pension Plan Other Benefits Plan 2025 $ 5,412 $ 1,303 2026 5,399 1,368 2027 5,479 1,410 2028 5,595 1,444 2029 5,581 1,541 2030-2034 29,746 8,682 Totals $ 57,212 $ 15,748 Benefit Plans Assets The allocation of plan assets at December 31, 2024 and 2023 by asset category is as follows: Pension Plan Other Benefits Plan Asset Category 2024 2023 Target 2024 2023 Target Equity Securities 31.8% 58.1% 30% 65.2% 60.9% 43% Debt Securities 67.9% 39.6% 68% 33.0% 36.1% 50% Cash 0.3% 0.7% 2% 1.8% 3.0% 2% Real Estate/Commodities 0.0% 1.6% 0% 0.0% 0.0% 5% Total 100.0% 100.0% 100.0% 100.0% Two outside investment firms each manage a portion of the Pension Plan asset portfolio. One of those investment firms also manages the Other Benefits Plan asset portfolio. Quarterly meetings are held between the Company’s Pension Committee of the Board of Directors and the investment managers to review their performance and asset allocation. If the actual asset allocation is outside the targeted range, the Pension Committee reviews current market conditions and advice provided by the investment managers to determine the appropriateness of rebalancing the portfolio. The objective of the Company is to maximize the long-term return on retirement plan assets, relative to a reasonable level of risk, maintain a diversified investment portfolio and maintain compliance with the Employee Retirement Income Security Act of 1974. The expected long-term rate of return is based on the various asset categories in which plan assets are invested and the current expectations and historical performance for these categories. Fair Value Measurements Accounting guidance provides a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described as follows: ● Level 1 – Inputs to the valuation methodology are unadjusted quoted market prices for identical assets or liabilities in accessible active markets. ● Level 2 – Inputs to the valuation methodology that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. If the asset or liability has a specified contractual term, the Level 2 input must be observable for substantially the full term of the asset or liability. ● Level 3 – Inputs to the valuation methodology are unobservable and significant to the fair value measurement. Certain investments in cash and cash equivalents, equity securities, and commodities are valued based on quoted market prices in active markets and are classified as Level 1 investments. Certain investments in cash and cash equivalents, equity securities and fixed income securities are valued using prices received from pricing vendors that utilize observable inputs and are therefore classified as Level 2 investments. The following tables present Middlesex’s Pension Plan assets measured and recorded at fair value within the fair value hierarchy: (In Thousands) As of December 31, 2024 Level 1 Level 2 Level 3 Total Mutual Funds $ 31,187 $ — $ — $ 31,187 Money Market Funds 293 — — 293 Common Equity Securities 195 — — 195 Corporate Bonds 42,974 — — 42,974 Agency/US Debt 19,041 — — 19,041 Sovereign/Non-US Debt 4,958 — — 4,958 Total Investments $ 98,648 $ — $ — $ 98,648 (In Thousands) As of December 31, 2023 Level 1 Level 2 Level 3 Total Mutual Funds $ 71,236 $ — $ — $ 71,236 Money Market Funds 663 — — 663 Common Equity Securities 12,544 — — 12,544 Corporate Bonds 5,091 — — 5,091 Agency/US Debt 1,854 — — 1,854 Sovereign/Non-US Debt 958 — — 958 Total Investments $ 92,346 $ — $ — $ 92,346 The following tables present Middlesex’s Other Benefits Plan assets measured and recorded at fair value within the fair value hierarchy: (In Thousands) As of December 31, 2024 Level 1 Level 2 Level 3 Total Mutual Funds $ 34,545 $ — $ — $ 34,545 Money Market Funds 977 — — 977 Agency/US/State/Municipal Debt — 17,505 — 17,505 Total Investments $ 35,522 $ 17,505 $ — $ 53,027 (In Thousands) As of December 31, 2023 Level 1 Level 2 Level 3 Total Mutual Funds $ 29,437 $ — $ — $ 29,437 Money Market Funds 1,429 — — 1,429 Agency/US/State/Municipal Debt — 17,486 — 17,486 Total Investments $ 30,866 $ 17,486 $ — $ 48,352 Benefit Plans Contributions For the Pension Plan, Middlesex made total cash contributions of $2.8 million in 2024 and expects to make approximately $0.9 million of cash contributions in 2025. For the Other Benefits Plan, Middlesex made total cash contributions of $0.9 million in 2024 and expects to make approximately $1.0 million of cash contributions in 2025. 401(k) Plan The Company maintains a 401(k) defined contribution plan, which covers substantially all employees (temporary employee needs to complete at least 1,000 hours of service to be eligible). Under the terms of the plan, the Company matches 100% of a participant’s contributions, which do not exceed 1% of a participant’s compensation, plus 50% of a participant’s contributions exceeding 1%, but not more than 6%. The Company’s matching contribution was $0.8 million, $0.8 million and $0.7 million for the years ended December 31, 2024, 2023 and 2022, respectively. Employees hired after March 31, 2007 are not eligible to participate in the Pension Plan and are generally eligible to participate in a discretionary profit sharing plan administered through the 401(k) plan. In December each year, the Board of Directors may approve that a stated percentage of eligible compensation be contributed to the account of the employee participant in the first quarter of the following year. For those employees still actively employed on December 31, 2024 or retired during the current year, the Company will fund a discretionary contribution of $1.1 million before April 1, 2025, which represents 5.0% of eligible 2024 compensation. For the years ended December 31, 2023 and 2022, the Company made qualifying discretionary contributions of $0.9 million for each year. Stock-Based Compensation The Company maintains a long-term incentive compensation plan for certain management employees where awards are made in the form of restricted common stock. Shares of restricted stock issued under the plan are subject to forfeiture by the employee in the event of termination of employment for any reason within three or five years of the award, as applicable, other than as a result of retirement at normal retirement age, death, disability or change in control. The maximum number of shares authorized for award under the plan is 300,000 shares, of which approximately 70% remain available for issuance. The Company recognizes compensation expense at fair value for the plan awards in accordance with ASC 718, Compensation – Stock Compensation The following table presents awarded but not yet vested share information for the plan: Shares(thousands) Unearned Weighted Balance, January 1, 2022 83 $ 1,931 Granted 11 1,151 $ 105.17 Vested (17 ) Amortization of Compensation expense — (1,350 ) Balance, December 31, 2022 77 1,732 Granted 15 1,165 $ 77.63 Vested (18 ) — Amortization of Compensation expense — (1,854 ) Balance, December 31, 2023 74 1,043 Granted 19 1,003 $ 52.50 Vested (58 ) — Amortization of Compensation expense — (1,140 ) Balance, December 31, 2024 35 $ 906 Unearned compensation is recognized over a period of 4 years.

Business Segment Data

Business Segment Data	12 Months Ended
	Dec. 31, 2024
Business Segment Data [Abstract]
Business Segment Data	Note 8 – Business Segment Data The Company’s Chief Operating Decision Maker (CODM) consists of the Company’s Chief Executive Officer, Chief Financial Officer, and Chief Operating Officer. The CODM evaluates segment performance and profitability using net income. This metric provides a clear, consistent basis for analyzing the financial results of each segment and supports decision-making regarding the allocation of resources. Resource allocation to the Company’s regulated and non-regulated segments begins with the annual budgeting process, which establishes initial funding and resource levels for each segment. The budget incorporates key financial and operational inputs, including anticipated revenues, expenses, capital and financing requirements, aligning with the Company’s strategic objectives and regulatory obligations. The CODM reviews budget-to-actual variances on a monthly, quarterly and year to-date basis and makes interim decisions to reallocate resources among segments as needed, ensuring a timely and effective response to changing conditions. For the regulated segment, the CODM uses this assessment to determine whether the segment is achieving its regulatory authorized rate of return. The segments follow the same accounting policies as described in Note 1 – Organization, Summary of Significant Accounting Policies and Recent Developments The Company has identified two reportable segments. One is the regulated business of collecting, treating and distributing water on a retail and wholesale basis to residential, commercial, industrial and fire protection customers in parts of New Jersey and Delaware and includes Middlesex, Tidewater, Pinelands Water and Southern Shores. This segment also includes a regulated wastewater system in New Jersey, Pinelands Wastewater. The Company is subject to regulations as to its rates, services and other matters by the states of New Jersey and Delaware with respect to utility service within these states. The other segment is primarily comprised of non-regulated contract services for the operation and maintenance of municipal and private water and wastewater systems in New Jersey and Delaware and includes USA, USA-PA, and White Marsh. (In Thousands) Years Ended December 31, Operation by Segments 2024 2023 2022 Revenues: Regulated $ 179,359 $ 154,617 $ 151,117 Non – Regulated 13,552 12,773 12,446 Inter-segment Elimination (1,034 ) (1,116 ) (1,129 ) Consolidated Revenues $ 191,877 $ 166,274 $ 162,434 Operating Expenses Purchased Water: Regulated $ 8,064 $ 9,144 $ 7,777 Non – Regulated — — — Inter-segment Elimination (567 ) (663 ) (688 ) Consolidated Purchased Water $ 7,497 $ 8,481 $ 7,089 Other Operations and Maintenance Expenses: Regulated $ 76,483 $ 66,670 $ 64,170 Non – Regulated 8,850 8,415 8,278 Inter-segment Elimination (467 ) (453 ) (441 ) Consolidated Other Operations and Maintenance Expenses $ 84,866 $ 74,632 $ 72,007 Other Taxes: Regulated $ 21,644 $ 18,504 $ 17,963 Non – Regulated 230 240 245 Consolidated Other Taxes $ 21,874 $ 18,744 $ 18,208 Depreciation: Regulated $ 24,173 $ 24,931 $ 22,783 Non – Regulated 257 263 246 Consolidated Depreciation $ 24,430 $ 25,194 $ 23,029 Operating Income: Regulated $ 49,462 $ 35,820 $ 44,257 Non – Regulated 3,748 3,403 3,076 Consolidated Operating Income $ 53,210 $ 39,223 $ 47,333 Other Income (Expense), Net: Regulated $ 12,195 $ 6,637 $ 7,898 Non – Regulated 281 214 279 Inter-segment Elimination (407 ) (366 ) (474 ) Consolidated Other Income (Expense), Net $ 12,069 $ 6,485 $ 7,703 (In Thousands) Years Ended December 31, Operation by Segments (continued) 2024 2023 2022 Interest Expense: Regulated $ 14,430 $ 13,508 $ 9,833 Non – Regulated — — 7 Inter-segment Elimination (407 ) (365 ) (473 ) Consolidated Interest Expense $ 14,023 $ 13,143 $ 9,367 Income Taxes: Regulated $ 5,653 $ (146 ) $ 2,084 Non – Regulated 1,252 1,187 1,156 Consolidated Income Taxes $ 6,905 $ 1,041 $ 3,240 Net Income: Regulated $ 41,575 $ 29,094 $ 40,229 Non – Regulated 2,776 2,430 2,200 Consolidated Net Income 44,351 31,524 42,429 Capital Expenditures: Regulated $ 74,584 $ 90,047 $ 91,054 Non – Regulated 38 132 281 Total Capital Expenditures $ 74,622 $ 90,179 $ 91,335 (In Thousands) As of As of December 31, 2024 December 31, 2023 Assets: Regulated $ 1,264,472 $ 1,235,549 Non – Regulated 7,671 8,068 Inter-segment Elimination (16,969 ) (7,565 ) Consolidated Assets $ 1,255,174 $ 1,236,052

Quarterly Data - Unaudited

Quarterly Data - Unaudited	12 Months Ended
	Dec. 31, 2024
Quarterly Data - Unaudited [Abstract]
Quarterly Data - Unaudited	Note 9 - Quarterly Data - Unaudited Financial information for each quarter of 2024 and 2023 is as follows: (In Thousands of Dollars, Except Per Share Data) 2024 1 st 2 nd 3 rd 4 th Total Operating Revenues $ 40,524 $ 49,146 $ 55,100 $ 47,107 $ 191,877 Operating Income 9,865 15,315 17,501 10,529 53,210 Net Income 10,682 10,546 14,319 8,804 44,351 Basic Earnings per Share $ 0.60 $ 0.59 $ 0.80 $ 0.49 $ 2.48 Diluted Earnings per Share $ 0.59 $ 0.59 $ 0.80 $ 0.49 $ 2.47 Common Dividend Per Share $ 0.3250 $ 0.3250 $ 0.3250 $ 0.3400 $ 1.3150 High/Low Common Stock Price $50.33/$64.71 $45.84/$58.02 $52.74/$67.59 $52.62/$69.70 2023 1 st 2 nd 3 rd 4 th Total Operating Revenues $ 38,156 $ 42,801 $ 46,715 $ 38,602 $ 166,274 Operating Income 7,490 10,669 12,822 8,242 39,223 Net Income 5,868 9,901 9,990 5,765 31,524 Basic Earnings per Share $ 0.33 $ 0.56 $ 0.56 $ 0.32 $ 1.77 Diluted Earnings per Share $ 0.33 $ 0.55 $ 0.56 $ 0.32 $ 1.76 Common Dividend Per Share $ 0.3125 $ 0.3125 $ 0.3125 $ 0.3250 $ 1.2625 High/Low Common Stock Price $72.64/$90.56 $66.51/$84.38 $65.37/$84.35 $61.34/$73.47 The information above, in the opinion of the Company, includes all adjustments consisting only of normal recurring accruals necessary for a fair presentation of such amounts. The business of the Company is subject to seasonal fluctuation with the peak period usually occurring during the summer months. The quarterly earnings per share amounts above may differ slightly from previous filings due to the effects of rounding.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ 8,804	$ 14,319	$ 10,546	$ 10,682	$ 5,765	$ 9,990	$ 9,901	$ 5,868	$ 44,351	$ 31,524	$ 42,429

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Cybersecurity Risk Management a

Cybersecurity Risk Management and Strategy Disclosure	12 Months Ended
	Dec. 31, 2024
Cybersecurity Risk Management, Strategy, and Governance [Line Items]
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]	Cybersecurity Program The Company’s cybersecurity program is an integral element of the Company's overarching strategic plan and risk management system. The robustness of the cybersecurity initiatives directly impact the realization of the Company's mission, vision, and goals. Aligned with the National Institute of Standards and Technology Cyber Security Framework, the Company employs a comprehensive "defense-in-depth" strategy, deploying multiple security measures to safeguard its operational environment and data integrity systems. The Company continually evaluates and refines its cybersecurity program in response to key factors such as evolving threat landscapes, program maturation, gap analysis, and guidance from external security consultants. The Company’s cybersecurity program relies on three key pillars: People, Process and Technology (PPT) to deliver a robust cybersecurity program. The cybersecurity program includes various aspects of PPT, including, but not limited to: ● Technology: ● Identity and Access Control Management Tools: ● Cybersecurity Processes: ● Incident Response Training: ● Cyber Risk Awareness and Training: Our Chief Technology Officer (CTO), with over 25 years of experience in various disciplines of information technology, oversees the cybersecurity program. Reporting to the Chief Executive Officer, the CTO provides regular briefs to the Board of Directors (the Board) and executive management, informing them about prevention, detection, mitigation, and remediation of cybersecurity incidents, as well as ongoing risks and threats. In our industry, the continuous functioning of information systems is of the utmost importance. Leveraging information technology systems, we collect, process and safeguard sensitive data and utilize automated tools to operate our plants. Cybersecurity threats encompass potential hazards such as malicious code, employee misconduct, advanced persistent threats, fraud, and phishing attacks. These risks have the potential to lead to information technology system failures, threat to water supply, or compromise of sensitive information. Our cybersecurity program aims to protect the uninterrupted availability of critical information technology resources. Regular assessments, conducted both internally and by third parties, evaluate our program against industry standards, including the National Institute of Standards and Technology Cybersecurity Standard and the Risk Management Framework. Although we have not experienced cybersecurity breaches or incidents that have significantly impacted our financial condition, results of operations, or business strategy, the effectiveness of our measures to prevent, detect, mitigate, or recover is based on currently known threats and recovery methods. There is no guarantee that cybersecurity breaches or incidents will not impact our business operations, strategy, financial condition, or operations. The ever-evolving landscape of cybersecurity threats introduces ongoing challenges. The Company recognizes the increasing frequency and sophistication of these threats. Despite implementing measures to secure operational and technology systems and fostering a culture of continuous improvement, the dynamic nature of cyber-attacks and vulnerabilities implies that these defenses may not be foolproof. Cybersecurity Risk Management Program and Strategy Cybersecurity risk management strategy is an integral component of our operations and our overall risk management process. Recognizing the dynamic nature of cybersecurity threats, we have implemented a comprehensive risk management program that aims to identify, assess, and mitigate potential risks. Our strategy involves a proactive approach, incorporating preventative measures, continuous monitoring, and adaptive response mechanisms. We prioritize the safeguarding of our operational network environment, sensitive data, including confidential business information and personal details of our customers and employees. Regular assessments conducted both internally and by third parties ensure our cybersecurity program aligns with industry standards. In addition to a dedicated cybersecurity team, we employ a defense-in-depth strategy, utilizing multiple security measures to protect our information technology system. Collaboration with third-party experts, industry peers and ongoing training initiatives ensures our cybersecurity strategy remains robust and responsive to evolving threats. We understand the importance of maintaining a vigilant and adaptive stance in the ever-evolving landscape of cybersecurity to safeguard our business operations, financial stability, and as a direct result, our overall success. Key elements of our cybersecurity risk mitigation approach are comprised of: ● A dedicated cybersecurity team; ● Collaboration with a third-party managed detection and response company for 24/7 monitoring and response; ● Cybersecurity insurance to cover a portion of losses and damages resulting from cyber-attacks or security breaches; ● An incident response team that is comprised of various departments required for an effective response; ● Conducting periodic drills and exercises, including industry collaborations and participation from the executive team; ● Continuous information security awareness training and phishing simulation exercises; ● Regular security assessments to address evolving risks and threats; ● Deployment of automation solutions to strengthen detection and response capabilities; and ● Utilizing services offered by the United States Department of Homeland Security to assist with resiliency planning. Third-Party Relationships The Company utilizes partners and third-party service providers to help deliver safe and reliable water and wastewater services across its regulated operations. In connection with these relationships, we perform due diligence, cyber risk scoring, cybersecurity related contractual obligations, and periodic reviews of third-party control environments to ensure alignment with the Company's risk exposure, business requirements, and risk tolerances. We extend our cybersecurity focus to third-party service providers by evaluating and monitoring their cybersecurity risks. High-risk vendors undergo continuous monitoring, and we maintain contractual agreements that mandate our third-party providers’ commitment to managing cybersecurity risks, providing incident notifications, and being subject to cybersecurity audits.
Cybersecurity Risk Role of Management [Text Block]	The Company’s cybersecurity program is an integral element of the Company's overarching strategic plan and risk management system. The robustness of the cybersecurity initiatives directly impact the realization of the Company's mission, vision, and goals. Aligned with the National Institute of Standards and Technology Cyber Security Framework, the Company employs a comprehensive "defense-in-depth" strategy, deploying multiple security measures to safeguard its operational environment and data integrity systems. The Company continually evaluates and refines its cybersecurity program in response to key factors such as evolving threat landscapes, program maturation, gap analysis, and guidance from external security consultants. The Company’s cybersecurity program relies on three key pillars: People, Process and Technology (PPT) to deliver a robust cybersecurity program. The cybersecurity program includes various aspects of PPT, including, but not limited to: ● Technology: ● Identity and Access Control Management Tools: ● Cybersecurity Processes: ● Incident Response Training: ● Cyber Risk Awareness and Training:
Cybersecurity Risk Management Expertise of Management Responsible [Text Block]	Our Chief Technology Officer (CTO), with over 25 years of experience in various disciplines of information technology, oversees the cybersecurity program.
Cybersecurity Risk Management Positions or Committees Responsible [Text Block]	Reporting to the Chief Executive Officer, the CTO provides regular briefs to the Board of Directors (the Board) and executive management, informing them about prevention, detection, mitigation, and remediation of cybersecurity incidents, as well as ongoing risks and threats.
Cybersecurity Risk Management Positions or Committees Responsible [Flag]	true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Text Block]	Although we have not experienced cybersecurity breaches or incidents that have significantly impacted our financial condition, results of operations, or business strategy, the effectiveness of our measures to prevent, detect, mitigate, or recover is based on currently known threats and recovery methods. There is no guarantee that cybersecurity breaches or incidents will not impact our business operations, strategy, financial condition, or operations.
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]	false
Cybersecurity Risk Management Third Party Engaged [Flag]	true
Cybersecurity Risk Board of Directors Oversight [Text Block]	Cybersecurity Governance The Corporate Governance and Nominating Committee of the Board is tasked with serving as the Board of Director’s primary body to oversee management’s risk identification, management and mitigation strategies related to, among other risks, information technology, cybersecurity and data security risks. Management, including the CTO, provides regular reports to the Board covering aspects such as risks, threats, the evolving threat landscape, enhancements to the cybersecurity program, and the preparedness of internal responses.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]	Management, including the CTO, provides regular reports to the Board covering aspects such as risks, threats, the evolving threat landscape, enhancements to the cybersecurity program, and the preparedness of internal responses.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]	The Company utilizes partners and third-party service providers to help deliver safe and reliable water and wastewater services across its regulated operations. In connection with these relationships, we perform due diligence, cyber risk scoring, cybersecurity related contractual obligations, and periodic reviews of third-party control environments to ensure alignment with the Company's risk exposure, business requirements, and risk tolerances.

Accounting Policies, by Policy

Accounting Policies, by Policy (Policies)	12 Months Ended
	Dec. 31, 2024
Organization, Summary of Significant Accounting Policies and Recent Developments [Abstract]
Organization	(a) Organization Middlesex has operated as a water utility in New Jersey since 1897 and in Delaware, through our wholly-owned subsidiary, Tidewater, since 1992. We are in the business of providing an essential water utility service for domestic, commercial, municipal, industrial and fire protection purposes. We also operate New Jersey municipal water, wastewater and storm water systems under contract and provide unregulated water and wastewater services in New Jersey and Delaware through our subsidiaries. Our rates charged to customers for water and wastewater services, the quality of services we provide and certain other matters are regulated in New Jersey and Delaware by the New Jersey Board of Public Utilities (NJBPU) and the Delaware Public Service Commission (DEPSC), respectively. Our USA, USA-PA and White Marsh subsidiaries are not regulated utilities.
Principles of Consolidation	(b) Principles of Consolidation –
System of Accounts	(c) System of Accounts –
Regulatory Accounting	(d) Regulatory Accounting Regulated Operations In accordance with ASC 980, Regulated Operations Rate and Regulatory Matters
Retirement Benefit Plans	(e) Retirement Benefit Plans The Company’s costs for providing retirement benefits are dependent upon numerous factors, including actual plan experience and assumptions of future experience. Retirement benefit plan obligations and expense are determined based on investment performance, discount rates and various other demographic factors related to the population participating in the Company’s retirement benefit plans, all of which can change significantly in future years. For more information on the Company’s Retirement Benefit Plans, see Note 7 – Employee Benefit Plans
Utility Plant	(f) Utility Plant –
Depreciation	(g) Depreciation – Source of Supply 1.15% - 3.44% Transmission and Distribution (T&D): Pumping 2.00% - 5.39% T&D – Mains 1.10% - 3.13% Water Treatment 1.65% - 7.09% T&D – Services 2.12% - 3.16% General Plant 2.08% - 17.84% T&D – Other 1.61% - 4.63% Wastewater Collection 1.42% - 1.81% Non-regulated fixed assets consist primarily of office buildings, furniture and fixtures, and transportation equipment. These assets are recorded at original cost and depreciation is calculated based on the estimated useful lives, ranging from 3 to 42 years.
Advances for Construction	(i) Advances for Construction – CIAC In accordance with regulatory requirements, Advances for Construction and CIAC are not depreciated. In addition, these amounts reduce the investment base for purposes of setting rates.
Allowance for Funds Used During Construction (AFUDC)	(j) Allowance for Funds Used During Construction (AFUDC) 2024 2023 2022 Middlesex 6.64% 6.35% 6.35% Tidewater 7.92% 7.92% 7.92%
Accounts Receivable	(k) Accounts Receivable
Revenues	(l) Revenues The Company’s regulated revenue results from tariff-based water and wastewater utility services to residential, industrial, commercial, fire-protection and wholesale customers. Residential customers are billed quarterly while most industrial, commercial, fire-protection and wholesale customers are billed monthly. Payments by customers are due between 15 to 30 days after the invoice date. Revenue is recognized as the water and wastewater services are delivered to customers which includes an accrual of unbilled revenues estimated from the last meter reading date to the end of the accounting period utilizing factors such as historical customer data and regional weather indicators. Unearned Revenues and Advance Service Fees include fixed service charge billings in advance to Tidewater customers recognized as service is provided to the customer. Non-regulated service contract revenues consist of base service fees as well as fees for additional billable services provided to customers. Fees are billed monthly and are due within 30 days after the invoice date. The Company considers the amounts billed to represent the value of these services provided to customers. These contracts expire at various times through 2032 and contain remaining performance obligations for which the Company expects to recognize revenue in the future. These contracts also contain customary termination provisions. Substantially all of the amounts included in operating revenues and accounts receivable are from contracts with customers. The Company’s contracts do not contain any significant financing components. The Company’s operating revenues are comprised of the following: (In Thousands) Years Ended December 31, 2024 2023 2022 Regulated Tariff Sales Residential $ 97,802 $ 86,581 $ 84,950 Commercial 31,833 23,945 22,689 Industrial 13,842 11,586 11,152 Fire Protection 14,188 12,582 12,726 Wholesale 21,003 19,117 18,769 Non-Regulated Contract Operations 13,085 12,320 12,006 Total Revenue from Contracts with Customers $ 191,753 $ 166,131 $ 162,292 Other Regulated Revenues 691 806 831 Other Non-Regulated Revenues 467 453 440 Inter-segment Elimination (1,034 ) (1,116 ) (1,129 ) Total Revenue $ 191,877 $ 166,274 $ 162,434
Unamortized Debt Expense and Premiums on Long-Term Debt	(m) Unamortized Debt Expense and Premiums on Long-Term Debt
Income Taxes	(n) Income Taxes Income Taxes
Cash and Cash Equivalents	(o) Cash and Cash Equivalents
Use of Estimates	(p) Use of Estimates
Recent Accounting Pronouncements	(q) Recent Accounting Pronouncements Standard Description Date of Adoption Application Effect on the Accounting Standards Update (“ASU”) 2023-07 “Improvements to Reportable Segment Disclosures” The ASU requires disclosure of significant segment expenses, extends certain annual disclosures to interim periods, and additional qualitative disclosures regarding the chief operating decision maker. The ASU is effective for the Company beginning with its annual financial statements for the year ended December 31, 2024. Retrospective The Company adopted ASU 2023-07, including a recast of 2023 and 2022 information, by including additional required disclosures within the Notes to the Consolidated Financial Statements -see Note 8- Reportable Segments ASU 2023-09 “Improvements to Income Tax Disclosures” The ASU amends certain income tax disclosure requirements, including adding requirements to present the reconciliation of income tax expense computed at the statutory rate to actual income tax expense using both percentages and amounts and providing a disaggregation of income taxes paid. Further, certain disclosures are eliminated, including the current requirement to disclose information on changes in unrecognized tax benefits in the next 12 months. The ASU is effective for the Company beginning with its annual financial statements for the year ending December 31, 2025. Early adoption is permitted. Prospective, with retrospective application also permitted. The Company is currently evaluating the requirements of ASU 2023-09. ASU 2024-03 “Disaggregation of Income Statement Expenses” The ASU enhances disclosures related to income statement expenses to further disaggregate expenses in the footnotes to the financial statements. The standard requires disaggregation of any relevant expense caption presented on the face of the income statement that contains the following expense categories: purchases of inventory, employee compensation, depreciation, intangible asset amortization, and depletion. Further, the standard requires disclosure of the total amount and the entity’s definition of selling expenses. The ASU is effective for the Company beginning with its annual financial statements for the year ended December 31, 2027. Prospective, with retrospective application also permitted. The Company is currently evaluating the requirements of ASU 2024-03.
Reclassifications	(r) Reclassifications –

Organization, Summary of Sign_2

Organization, Summary of Significant Accounting Policies and Recent Developments (Tables)	12 Months Ended
	Dec. 31, 2024
Organization, Summary of Significant Accounting Policies and Recent Developments [Abstract]
Schedule of Range of Depreciation Rates for the Major Utility Plant Categories	The following table sets forth the range of depreciation rates for the major utility plant categories used to calculate depreciation for the years ended December 31, 2024, 2023, and 2022. These rates have been approved by the NJBPU or DEPSC: Source of Supply 1.15% - 3.44% Transmission and Distribution (T&D): Pumping 2.00% - 5.39% T&D – Mains 1.10% - 3.13% Water Treatment 1.65% - 7.09% T&D – Services 2.12% - 3.16% General Plant 2.08% - 17.84% T&D – Other 1.61% - 4.63% Wastewater Collection 1.42% - 1.81%
Schedule of AFUDC Rates for Middlesex and Tidewater	The AFUDC rates for the years ended December 31, 2024, 2023 and 2022 for Middlesex and Tidewater are as follows: 2024 2023 2022 Middlesex 6.64% 6.35% 6.35% Tidewater 7.92% 7.92% 7.92%
Schedule of Operating Revenues	The Company’s operating revenues are comprised of the following: (In Thousands) Years Ended December 31, 2024 2023 2022 Regulated Tariff Sales Residential $ 97,802 $ 86,581 $ 84,950 Commercial 31,833 23,945 22,689 Industrial 13,842 11,586 11,152 Fire Protection 14,188 12,582 12,726 Wholesale 21,003 19,117 18,769 Non-Regulated Contract Operations 13,085 12,320 12,006 Total Revenue from Contracts with Customers $ 191,753 $ 166,131 $ 162,292 Other Regulated Revenues 691 806 831 Other Non-Regulated Revenues 467 453 440 Inter-segment Elimination (1,034 ) (1,116 ) (1,129 ) Total Revenue $ 191,877 $ 166,274 $ 162,434
Schedule of Issued Accounting Standards	The recently issued accounting standards and their impact on the Company as of December 31, 2024 are as follows: Standard Description Date of Adoption Application Effect on the Accounting Standards Update (“ASU”) 2023-07 “Improvements to Reportable Segment Disclosures” The ASU requires disclosure of significant segment expenses, extends certain annual disclosures to interim periods, and additional qualitative disclosures regarding the chief operating decision maker. The ASU is effective for the Company beginning with its annual financial statements for the year ended December 31, 2024. Retrospective The Company adopted ASU 2023-07, including a recast of 2023 and 2022 information, by including additional required disclosures within the Notes to the Consolidated Financial Statements -see Note 8- Reportable Segments ASU 2023-09 “Improvements to Income Tax Disclosures” The ASU amends certain income tax disclosure requirements, including adding requirements to present the reconciliation of income tax expense computed at the statutory rate to actual income tax expense using both percentages and amounts and providing a disaggregation of income taxes paid. Further, certain disclosures are eliminated, including the current requirement to disclose information on changes in unrecognized tax benefits in the next 12 months. The ASU is effective for the Company beginning with its annual financial statements for the year ending December 31, 2025. Early adoption is permitted. Prospective, with retrospective application also permitted. The Company is currently evaluating the requirements of ASU 2023-09. ASU 2024-03 “Disaggregation of Income Statement Expenses” The ASU enhances disclosures related to income statement expenses to further disaggregate expenses in the footnotes to the financial statements. The standard requires disaggregation of any relevant expense caption presented on the face of the income statement that contains the following expense categories: purchases of inventory, employee compensation, depreciation, intangible asset amortization, and depletion. Further, the standard requires disclosure of the total amount and the entity’s definition of selling expenses. The ASU is effective for the Company beginning with its annual financial statements for the year ended December 31, 2027. Prospective, with retrospective application also permitted. The Company is currently evaluating the requirements of ASU 2024-03.

Rate and Regulatory Matters (Ta

Rate and Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2024
Rate and Regulatory Matters [Abstract]
Schedule of Unamortized Balances	These items are detailed as follows: (In Thousands) December 31, Regulatory Assets 2024 2023 Income Taxes (a) $ 89,825 $ 84,419 Other (b) 11,958 6,275 Total $ 101,783 $ 90,694 Regulatory Liabilities Income Taxes (c) $ 27,380 $ 28,188 Cost of Removal (d) 20,595 19,727 Employee Benefit Plans (e) 9,435 1,471 Lawsuit Settlement (f) 5,334 63,635 New Jersey Revenue Taxes (g) 1,813 — Total $ 64,557 $ 113,021 (a) The recovery period for income taxes is dependent upon when the temporary differences between the tax and book treatment of various items reverse. (b) Other primarily includes deferred costs for rate cases and tank painting. (c) The 2017 Tax Act reduced the statutory corporate federal income tax rate from 35% to 21%. The tariff rates charged to customers effective prior to 2018 in the Company’s regulated companies include recovery of income taxes at the statutory rate in effect at the time those rates were approved by the respective state public utility commissions. The Company has recorded regulatory liabilities for excess income taxes collected through rates due to the lower income tax rate under the 2017 Tax Act. These regulatory liabilities are overwhelmingly related to utility plant depreciation deduction timing differences, which are subject to Internal Revenue Service (IRS) normalization rules. The IRS rules limit how quickly the excess taxes attributable to accelerated taxes can be returned to customers. The current base rates for Middlesex and Pinelands customers became effective after 2017 and reflect the impact of the 2017 Tax Act. (d) The Company uses composite depreciation rates for its regulated utility assets, which is currently an acceptable method under GAAP and is widely used in the utility industry. Historically, under the composite depreciation method, the anticipated costs of removing assets upon retirement are provided for over the life of those assets as a component of depreciation expense. The Company recovers certain asset retirement costs through rates charged to customers as an approved component of depreciation expense. (e) Retirement benefits include pension and other retirement benefits that have been recorded on the Consolidated Balance Sheet in accordance with the guidance provided in ASC 715, Compensation – Retirement Benefits (f) The net proceeds available to Middlesex from the 3M Settlement Agreement were recorded as a regulatory liability and are being used for future related operating and maintenance costs. (g) Revenue related taxes paid by the Company's New Jersey Regulated subsidiaries, and reflected in those subsidiaries current base rates, were above enacted rates and will be refunded back to customers in a future rate proceeding.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2024
Income Taxes [Abstract]
Schedule of Income Tax Expense (Benefit)	Income tax expense (benefit) differs from the amount computed by applying the statutory rate on book income subject to tax for the following reasons: (In Thousands) Years Ended December 31, 2024 2023 2022 Income Tax at Statutory Rate $ 10,764 $ 6,839 $ 9,590 Tax Effect of: Utility Plant Related (659 ) (1,495 ) (1,106 ) Tangible Property Repairs (4,535 ) (5,475 ) (6,767 ) State Income Taxes – Net 1,270 1,117 1,296 Other 65 55 227 Total Income Tax Expense $ 6,905 $ 1,041 $ 3,240
Schedule of Income Tax Expense (Benefit) is Comprised	Income tax expense (benefit) is comprised of the following: (In Thousands) Years Ended December 31, 2024 2023 2022 Current: Federal $ 1,554 $ 2,952 $ 425 State 1,126 1,066 1,381 Deferred: Federal 3,802 (3,261 ) 1,242 State 482 348 260 Investment Tax Credits (59 ) (64 ) (68 ) Total Income Tax Expense $ 6,905 $ 1,041 $ 3,240
Schedule of Deferred Income Taxes Reflect the Net Tax Effect	Deferred income taxes reflect the net tax effect of temporary differences between the carrying amounts of assets and liabilities for financial purposes and the amounts used for income tax purposes. The components of the net deferred tax liability are as follows: (In Thousands) December 31, 2024 2023 Utility Plant Related $ 95,877 $ 84,330 Customer Advances (3,525 ) (3,546 ) Employee Benefits 7,888 7,100 Investment Tax Credits 181 240 Other 814 612 Total Accumulated Deferred Income Taxes $ 101,235 $ 88,736

Commitments and Contingent Li_2

Commitments and Contingent Liabilities (Tables)	12 Months Ended
	Dec. 31, 2024
Commitments and Contingent Liabilities [Abstract]
Schedule of Purchased Water Costs	Purchased water costs are shown below: (In Millions) Years Ended December 31, 2024 2023 2022 Untreated $ 3.5 $ 3.2 $ 3.2 Treated 4.0 5.3 3.9 Total Costs $ 7.5 $ 8.5 $ 7.1
Schedule of Operating Lease ROU Assets	Information related to operating lease ROU assets is as follows: (In Millions) December 31, 2024 2023 ROU Asset at Lease Inception $ 7.3 $ 7.3 Accumulated Amortization (4.7 ) (4.1 ) Current ROU Asset $ 2.6 $ 3.2
Schedule of Future Minimum Operating Lease Commitments	The Company’s future minimum operating lease (In Millions) December 31, 2024 2025 $ 0.8 2026 0.8 2027 0.9 2028 0.9 2029 0.9 Total Lease Payments $ 4.3 Imputed Interest (1.3 ) Present Value of Lease Payments 3.0 Less Current Portion* (0.6 ) Non-Current Lease Liability $ 2.4 *Included in Other Current Liabilities

Short-Term Borrowings (Tables)

Short-Term Borrowings (Tables)	12 Months Ended
	Dec. 31, 2024
Short-Term Borrowings [Abstract]
Schedule of Short-Term Borrowings	Information regarding the Company’s short-term borrowings for the years ended December 31, 2024 and 2023 is summarized below: ($ In Millions) 2024 2023 Average Amount Outstanding $ 38.7 $ 35.7 Weighted Average Interest Rate 6.33% 6.13% Notes Payable at Year-End $ 23.0 $ 42.8 Weighted Average Interest Rate at Year-End 5.63% 6.50%
Schedule of Lines of Credit	The Company maintains bank lines of credit aggregating $140.0 million. (In Millions) As of December 31, 2024 Line of Credit Outstanding Available Maximum Credit Type Expiration Date Bank of America $ — $ 60.0 $ 60.0 Uncommitted January 23, 2026 PNC Bank 23.0 45.0 68.0 Committed January 31, 2027 CoBank, ACB (CoBank) — 12.0 12.0 Committed May 20, 2026 $ 23.0 $ 117.0 $ 140.0

Capitalization (Tables)

Capitalization (Tables)	12 Months Ended
	Dec. 31, 2024
Capitalization [Abstract]
Schedule of Long-Term Debt	The aggregate annual principal repayment obligations as of December 31, 2024 for all long-term debt over the next five years and thereafter are shown below: Year (In Millions) 2025 $ 7.7 2026 7.5 2027 7.3 2028 7.0 2029 6.5 Thereafter 323.4
Schedule of Basic and Diluted Earnings Per Share	The following table presents the calculation of basic and diluted earnings per share (EPS) of common stock for the years ended December 31, 2024, 2023 and 2022. Basic EPS is computed on the basis of the weighted average number of shares outstanding. Diluted EPS assumes the conversion of the Convertible Preferred Stock $7.00 Series. (In Thousands, Except Per Share Amounts) 2024 2023 2022 Basic: Income Shares Income Shares Income Shares Net Income $ 44,351 17,842 $ 31,524 17,732 $ 42,429 17,597 Preferred Dividend (112 ) (120 ) (120 ) Earnings Applicable to Common Stock $ 44,239 17,842 $ 31,404 17,732 $ 42,309 17,597 Basic EPS $ 2.48 $ 1.77 $ 2.40 Diluted: Earnings Applicable to Common Stock $ 44,239 17,842 $ 31,404 17,732 $ 42,309 17,597 Convertible Preferred $7.00 Series Dividend 46 104 67 115 67 115 Adjusted Earnings Applicable to Common Stock $ 44,285 17,946 $ 31,471 17,847 $ 42,376 17,712 Diluted EPS $ 2.47 $ 1.76 $ 2.39
Schedule of Carrying Amount and Fair Value of the Bonds	The carrying amount and fair value of the Bonds were as follows: (In Thousands) At December 31, 2024 2023 Carrying Fair Carrying Fair Amount Value Amount Value FMBs $ 129,602 $ 125,067 $ 133,374 $ 131,745

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2024
Employee Benefit Plans [Abstract]
Schedule of Employee Benefit Plans Recognized in Balance Sheet	The Company uses a December 31 measurement date for all of its employee benefit plans. The tables below set forth information relating to the Company’s Pension Plan and Other Benefits Plan for 2024 and 2023. (In Thousands) Pension Plan Other Benefits Plan Years Ended December 31, 2024 2023 2024 2023 Change in Projected Benefit Obligation: Beginning Balance $ 91,853 $ 87,788 $ 28,000 $ 32,909 Service Cost 1,270 1,551 320 391 Interest Cost 4,280 4,270 1,313 1,608 Actuarial (Gain) Loss (5,478 ) 1,966 (486 ) (5,968 ) Benefits Paid (4,424 ) (3,722 ) (946 ) (940 ) Ending Balance $ 87,501 $ 91,853 $ 28,201 $ 28,000
Schedule of Change in Fair Value of Plan Assets	(In Thousands) Pension Plan Other Benefits Plan Years Ended December 31, 2024 2023 2024 2023 Change in Fair Value of Plan Assets: Beginning Balance $ 92,346 $ 84,828 $ 48,352 $ 44,029 Actual Return on Plan Assets 7,976 10,840 4,675 4,323 Employer Contributions 2,750 400 946 940 Benefits Paid (4,424 ) (3,722 ) (946 ) (940 ) Ending Balance $ 98,648 $ 92,346 $ 53,027 $ 48,352 Funded Status $ 11,147 $ 494 $ 24,826 $ 20,352
Schedule of Employee Benefit Plans Recognized in Balance Sheet	(In Thousands) Pension Plan Other Benefits Plan As of December 31, 2024 2023 2024 2023 Amounts Recognized in the Consolidated Balance Sheets consist of: Current Liability $ 883 $ 933 $ — $ — Noncurrent Asset (12,030 ) (1,427 ) (24,826 ) (20,352 ) Net Asset Recognized $ (11,147 ) $ (494 ) $ (24,826 ) $ (20,352 )
Schedule of Components of Net Benefit Cost	(InThousands) Pension Plan Other Benefits Plan Years Ended December 31, 2024 2023 2022 2024 2023 2022 Components of Net Periodic Benefit Cost Service Cost $ 1,270 $ 1,551 $ 2,362 $ 320 $ 391 $ 799 Interest Cost 4,280 4,270 3,042 1,313 1,608 1,325 Expected Return on Plan Assets (6,322 ) (5,865 ) (7,041 ) (3,384 ) (3,082 ) (3,547 ) Amortization of Net Actuarial Loss (Gain) 153 658 1,674 (1,098 ) (191 ) — Net Periodic Benefit Cost* $ (619 ) $ 614 $ 37 $ (2,849 ) $ (1,274 ) $ (1,423 ) *
Schedule of Regulatory Assets into Net Periodic Benefit Cost	Amounts that are expected to be amortized from Regulatory Assets into Net Periodic Benefit Cost in 2025 are as follows: (In Thousands) Pension Other Actuarial Loss (Gain) $ 50 $ (1,127 )
Schedule of Discount and Compensation Rates	The discount rate and compensation increase rate for determining our postretirement benefit plans’ benefit obligations and costs as of and for the years ended December 31, 2024, 2023 and 2022, respectively, are as follows: Pension Plan Other Benefits Plan 2024 2023 2022 2024 2023 2022 Weighted Average Assumptions: Expected Return on Plan Assets 7.00% 7.00% 7.00% 7.00% 7.00% 7.00% Discount Rate for: Benefit Obligation 5.47% 4.79% 4.98% 5.49% 4.79% 4.98% Benefit Cost 4.79% 4.98% 2.72% 4.79% 4.98% 2.72% Compensation Increase for: Benefit Obligation 3.00% 3.00% 3.00% 3.00% 3.00% 3.00% Benefit Cost 3.00% 3.00% 3.00% 3.00% 3.00% 3.00%
Schedule of Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates	A one-percentage point change in assumed healthcare cost trend rates would have the following effects on the Other Benefits Plan: (In Thousands) 1 Percentage Point Increase Decrease Effect on Current Year Service and Interest Costs $ 228 $ (184 ) Effect on Projected Benefit Obligation $ 3,434 $ (2,824 )
Schedule of Expected Benefit Payments	The following benefit payments, which reflect expected future service, are expected to be paid: (In Thousands) Year Pension Plan Other Benefits Plan 2025 $ 5,412 $ 1,303 2026 5,399 1,368 2027 5,479 1,410 2028 5,595 1,444 2029 5,581 1,541 2030-2034 29,746 8,682 Totals $ 57,212 $ 15,748
Schedule of Allocation of Plan Assets	The allocation of plan assets at December 31, 2024 and 2023 by asset category is as follows: Pension Plan Other Benefits Plan Asset Category 2024 2023 Target 2024 2023 Target Equity Securities 31.8% 58.1% 30% 65.2% 60.9% 43% Debt Securities 67.9% 39.6% 68% 33.0% 36.1% 50% Cash 0.3% 0.7% 2% 1.8% 3.0% 2% Real Estate/Commodities 0.0% 1.6% 0% 0.0% 0.0% 5% Total 100.0% 100.0% 100.0% 100.0%
Schedule of Fair Value of Plan Assets	The following tables present Middlesex’s Pension Plan assets measured and recorded at fair value within the fair value hierarchy: (In Thousands) As of December 31, 2024 Level 1 Level 2 Level 3 Total Mutual Funds $ 31,187 $ — $ — $ 31,187 Money Market Funds 293 — — 293 Common Equity Securities 195 — — 195 Corporate Bonds 42,974 — — 42,974 Agency/US Debt 19,041 — — 19,041 Sovereign/Non-US Debt 4,958 — — 4,958 Total Investments $ 98,648 $ — $ — $ 98,648 (In Thousands) As of December 31, 2023 Level 1 Level 2 Level 3 Total Mutual Funds $ 71,236 $ — $ — $ 71,236 Money Market Funds 663 — — 663 Common Equity Securities 12,544 — — 12,544 Corporate Bonds 5,091 — — 5,091 Agency/US Debt 1,854 — — 1,854 Sovereign/Non-US Debt 958 — — 958 Total Investments $ 92,346 $ — $ — $ 92,346 (In Thousands) As of December 31, 2024 Level 1 Level 2 Level 3 Total Mutual Funds $ 34,545 $ — $ — $ 34,545 Money Market Funds 977 — — 977 Agency/US/State/Municipal Debt — 17,505 — 17,505 Total Investments $ 35,522 $ 17,505 $ — $ 53,027 (In Thousands) As of December 31, 2023 Level 1 Level 2 Level 3 Total Mutual Funds $ 29,437 $ — $ — $ 29,437 Money Market Funds 1,429 — — 1,429 Agency/US/State/Municipal Debt — 17,486 — 17,486 Total Investments $ 30,866 $ 17,486 $ — $ 48,352
Schedule of Table Presents Awarded but not Yet Vested Share	The following table presents awarded but not yet vested share information for the plan: Shares(thousands) Unearned Weighted Balance, January 1, 2022 83 $ 1,931 Granted 11 1,151 $ 105.17 Vested (17 ) Amortization of Compensation expense — (1,350 ) Balance, December 31, 2022 77 1,732 Granted 15 1,165 $ 77.63 Vested (18 ) — Amortization of Compensation expense — (1,854 ) Balance, December 31, 2023 74 1,043 Granted 19 1,003 $ 52.50 Vested (58 ) — Amortization of Compensation expense — (1,140 ) Balance, December 31, 2024 35 $ 906

Business Segment Data (Tables)

Business Segment Data (Tables)	12 Months Ended
	Dec. 31, 2024
Business Segment Data [Abstract]
Schedule of Inter-Segment Transactions	(In Thousands) Years Ended December 31, Operation by Segments 2024 2023 2022 Revenues: Regulated $ 179,359 $ 154,617 $ 151,117 Non – Regulated 13,552 12,773 12,446 Inter-segment Elimination (1,034 ) (1,116 ) (1,129 ) Consolidated Revenues $ 191,877 $ 166,274 $ 162,434 Operating Expenses Purchased Water: Regulated $ 8,064 $ 9,144 $ 7,777 Non – Regulated — — — Inter-segment Elimination (567 ) (663 ) (688 ) Consolidated Purchased Water $ 7,497 $ 8,481 $ 7,089 Other Operations and Maintenance Expenses: Regulated $ 76,483 $ 66,670 $ 64,170 Non – Regulated 8,850 8,415 8,278 Inter-segment Elimination (467 ) (453 ) (441 ) Consolidated Other Operations and Maintenance Expenses $ 84,866 $ 74,632 $ 72,007 Other Taxes: Regulated $ 21,644 $ 18,504 $ 17,963 Non – Regulated 230 240 245 Consolidated Other Taxes $ 21,874 $ 18,744 $ 18,208 Depreciation: Regulated $ 24,173 $ 24,931 $ 22,783 Non – Regulated 257 263 246 Consolidated Depreciation $ 24,430 $ 25,194 $ 23,029 Operating Income: Regulated $ 49,462 $ 35,820 $ 44,257 Non – Regulated 3,748 3,403 3,076 Consolidated Operating Income $ 53,210 $ 39,223 $ 47,333 Other Income (Expense), Net: Regulated $ 12,195 $ 6,637 $ 7,898 Non – Regulated 281 214 279 Inter-segment Elimination (407 ) (366 ) (474 ) Consolidated Other Income (Expense), Net $ 12,069 $ 6,485 $ 7,703 (In Thousands) Years Ended December 31, Operation by Segments (continued) 2024 2023 2022 Interest Expense: Regulated $ 14,430 $ 13,508 $ 9,833 Non – Regulated — — 7 Inter-segment Elimination (407 ) (365 ) (473 ) Consolidated Interest Expense $ 14,023 $ 13,143 $ 9,367 Income Taxes: Regulated $ 5,653 $ (146 ) $ 2,084 Non – Regulated 1,252 1,187 1,156 Consolidated Income Taxes $ 6,905 $ 1,041 $ 3,240 Net Income: Regulated $ 41,575 $ 29,094 $ 40,229 Non – Regulated 2,776 2,430 2,200 Consolidated Net Income 44,351 31,524 42,429 Capital Expenditures: Regulated $ 74,584 $ 90,047 $ 91,054 Non – Regulated 38 132 281 Total Capital Expenditures $ 74,622 $ 90,179 $ 91,335 (In Thousands) As of As of December 31, 2024 December 31, 2023 Assets: Regulated $ 1,264,472 $ 1,235,549 Non – Regulated 7,671 8,068 Inter-segment Elimination (16,969 ) (7,565 ) Consolidated Assets $ 1,255,174 $ 1,236,052

Quarterly Data - Unaudited (Tab

Quarterly Data - Unaudited (Tables)	12 Months Ended
	Dec. 31, 2024
Quarterly Data - Unaudited [Abstract]
Schedule of Financial Information	Financial information for each quarter of 2024 and 2023 is as follows: (In Thousands of Dollars, Except Per Share Data) 2024 1 st 2 nd 3 rd 4 th Total Operating Revenues $ 40,524 $ 49,146 $ 55,100 $ 47,107 $ 191,877 Operating Income 9,865 15,315 17,501 10,529 53,210 Net Income 10,682 10,546 14,319 8,804 44,351 Basic Earnings per Share $ 0.60 $ 0.59 $ 0.80 $ 0.49 $ 2.48 Diluted Earnings per Share $ 0.59 $ 0.59 $ 0.80 $ 0.49 $ 2.47 Common Dividend Per Share $ 0.3250 $ 0.3250 $ 0.3250 $ 0.3400 $ 1.3150 High/Low Common Stock Price $50.33/$64.71 $45.84/$58.02 $52.74/$67.59 $52.62/$69.70 2023 1 st 2 nd 3 rd 4 th Total Operating Revenues $ 38,156 $ 42,801 $ 46,715 $ 38,602 $ 166,274 Operating Income 7,490 10,669 12,822 8,242 39,223 Net Income 5,868 9,901 9,990 5,765 31,524 Basic Earnings per Share $ 0.33 $ 0.56 $ 0.56 $ 0.32 $ 1.77 Diluted Earnings per Share $ 0.33 $ 0.55 $ 0.56 $ 0.32 $ 1.76 Common Dividend Per Share $ 0.3125 $ 0.3125 $ 0.3125 $ 0.3250 $ 1.2625 High/Low Common Stock Price $72.64/$90.56 $66.51/$84.38 $65.37/$84.35 $61.34/$73.47

Organization, Summary of Sign_3

Organization, Summary of Significant Accounting Policies and Recent Developments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Organization, Summary of Significant Accounting Policies and Recent Developments [Line Items]
Percentage of operating revenues	93%
Percentage of total assets	99%
Allowance for credit losses	$ 2.7	$ 2.1
Bad debt expense	1.6	1	$ 0.5
Accounts receivable write-offs	$ 1	$ 1.2	$ 0.7
Middlesex [Member]
Organization, Summary of Significant Accounting Policies and Recent Developments [Line Items]
Ownership percentage	50%
Minimum [Member]
Organization, Summary of Significant Accounting Policies and Recent Developments [Line Items]
Estimated useful lives	3 years
Maximum [Member]
Organization, Summary of Significant Accounting Policies and Recent Developments [Line Items]
Estimated useful lives	42 years

Organization, Summary of Sign_4

Organization, Summary of Significant Accounting Policies and Recent Developments - Schedule of Range of Depreciation Rates for the Major Utility Plant Categories (Details)	12 Months Ended
	Dec. 31, 2024
Minimum [Member] | Source of Supply [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.15%
Minimum [Member] | Pumping [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	2%
Transmission and Distribution	1.10%
Minimum [Member] | Water Treatment [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.65%
Transmission and Distribution	2.12%
Minimum [Member] | General Plant [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	2.08%
Transmission and Distribution	1.61%
Minimum [Member] | Wastewater Collection [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.42%
Maximum [Member] | Source of Supply [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	3.44%
Maximum [Member] | Pumping [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	5.39%
Transmission and Distribution	3.13%
Maximum [Member] | Water Treatment [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	7.09%
Transmission and Distribution	3.16%
Maximum [Member] | General Plant [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	17.84%
Transmission and Distribution	4.63%
Maximum [Member] | Wastewater Collection [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.81%

Organization, Summary of Sign_5

Organization, Summary of Significant Accounting Policies and Recent Developments - Schedule of AFUDC Rates for Middlesex and Tidewater (Details)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Middlesex [Member]
Public Utilities, General Disclosures [Line Items]
Allowance for funds used during construction rates	6.64%	6.35%	6.35%
Tidewater [Member]
Public Utilities, General Disclosures [Line Items]
Allowance for funds used during construction rates	7.92%	7.92%	7.92%

Organization, Summary of Sign_6

Organization, Summary of Significant Accounting Policies and Recent Developments - Schedule of Operating Revenues (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Regulated Tariff Sales
Residential	$ 97,802	$ 86,581	$ 84,950
Commercial	31,833	23,945	22,689
Industrial	13,842	11,586	11,152
Fire Protection	14,188	12,582	12,726
Wholesale	21,003	19,117	18,769
Non-Regulated Contract Operations	13,085	12,320	12,006
Total Revenue from Contracts with Customers	191,753	166,131	162,292
Other Regulated Revenues	691	806	831
Other Non-Regulated Revenues	467	453	440
Inter-segment Elimination	(1,034)	(1,116)	(1,129)
Total Revenue	$ 191,877	$ 166,274	$ 162,434

Organization, Summary of Sign_7

Organization, Summary of Significant Accounting Policies and Recent Developments - Schedule of Issued Accounting Standards (Details)	12 Months Ended
	Dec. 31, 2024
Accounting Standards Update (“ASU”) 2023-07 “Improvements to Reportable Segment Disclosures” [Member]
Schedule of Issued Accounting Standards [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Description	The ASU requires disclosure of significant segment expenses, extends certain annual disclosures to interim periods, and additional qualitative disclosures regarding the chief operating decision maker.
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Dec. 31, 2024
Change in Accounting Principle, Accounting Standards Update, Retrospective Application Impracticable, Reason and Alternative Method, Description	Retrospective
New Accounting Pronouncement or Change in Accounting Principle, Description of Prior-period Information Retrospectively Adjusted	The Company adopted ASU 2023-07, including a recast of 2023 and 2022 information, by including additional required disclosures within the Notes to the Consolidated Financial Statements -see Note 8- Reportable Segments.
ASU 2023-09 “Improvements to Income Tax Disclosures” [Member]
Schedule of Issued Accounting Standards [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Description	The ASU amends certain income tax disclosure requirements, including adding requirements to present the reconciliation of income tax expense computed at the statutory rate to actual income tax expense using both percentages and amounts and providing a disaggregation of income taxes paid. Further, certain disclosures are eliminated, including the current requirement to disclose information on changes in unrecognized tax benefits in the next 12 months.
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Dec. 31, 2025
Change in Accounting Principle, Accounting Standards Update, Retrospective Application Impracticable, Reason and Alternative Method, Description	Prospective, with retrospective application also permitted.
New Accounting Pronouncement or Change in Accounting Principle, Description of Prior-period Information Retrospectively Adjusted	The Company is currently evaluating the requirements of ASU 2023-09.
ASU 2024-03 “Disaggregation of Income Statement Expenses” [Member]
Schedule of Issued Accounting Standards [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Description	The ASU enhances disclosures related to income statement expenses to further disaggregate expenses in the footnotes to the financial statements. The standard requires disaggregation of any relevant expense caption presented on the face of the income statement that contains the following expense categories: purchases of inventory, employee compensation, depreciation, intangible asset amortization, and depletion. Further, the standard requires disclosure of the total amount and the entity’s definition of selling expenses.
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Dec. 31, 2027
Change in Accounting Principle, Accounting Standards Update, Retrospective Application Impracticable, Reason and Alternative Method, Description	Prospective, with retrospective application also permitted.
New Accounting Pronouncement or Change in Accounting Principle, Description of Prior-period Information Retrospectively Adjusted	The Company is currently evaluating the requirements of ASU 2024-03.

Rate and Regulatory Matters (De

Rate and Regulatory Matters (Details) - USD ($) $ in Thousands					1 Months Ended				3 Months Ended								6 Months Ended	12 Months Ended
	Jan. 01, 2025	Nov. 26, 2024	May 26, 2024	Mar. 01, 2024	Feb. 28, 2025	Oct. 30, 2024	Aug. 31, 2024	Oct. 31, 2023	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Nov. 30, 2021
Rate and Regulatory Matters [Line Items]
Approved increase in annual operating revenues		$ 600	$ 500
Base rate amount								$ 5,500										$ 563,100
Return on equity																		9.60%
Reclassification regulatory liabilities																			$ 48,300
Depreciation																		$ 24,430	25,194	$ 23,029
Carrying costs																		4,100
Previously incurred operating treatment costs									$ 2,600								$ 2,600	2,600
Regulatory costs																	600
Distribution system improvement charge rate								5%
Annual operating revenue							$ 10,300
Percentage of current revenue							25.66%
Annual revenues									47,107	$ 55,100	$ 49,146	$ 40,524	$ 38,602	$ 46,715	$ 42,801	$ 38,156		191,877	166,274
Additional cost of purchased water																		7,500	8,500	7,100
Operations and maintenance expense																		92,363	83,113	$ 79,096
Utility assets									$ 156,829				$ 129,174				$ 156,829	$ 156,829	$ 129,174
Price index rate																		3%
New Jersey Board of Public Utilities [Member]
Rate and Regulatory Matters [Line Items]
Depreciation																		$ 900
Lead Service Line Replacement [Member]
Rate and Regulatory Matters [Line Items]
Previously incurred operating treatment costs											$ 1,200
Maximum [Member]
Rate and Regulatory Matters [Line Items]
Corporate tax rate																		35%
Minimum [Member]
Rate and Regulatory Matters [Line Items]
Corporate tax rate																		21%
Middlesex Water [Member] | New Jersey Board of Public Utilities [Member]
Rate and Regulatory Matters [Line Items]
Approved increase in annual operating revenues				$ 15,400
Maturity Less than 30 Days [Member] | Middlesex Water Company [Member]
Rate and Regulatory Matters [Line Items]
Escrow account																					$ 1,700
Tidewater [Member]
Rate and Regulatory Matters [Line Items]
Annual revenues						$ 2,500
Additional cost of purchased water																		$ 2,100
Operations and maintenance expense																		$ 1,800
Subsequent Event [Member]
Rate and Regulatory Matters [Line Items]
Approved increase in annual operating revenues	$ 100				$ 500
Utility assets					$ 4,600
Increase in annual operating revenues	6.51%

Rate and Regulatory Matters - S

Rate and Regulatory Matters - Schedule of Regulatory Assets and Liabilities (Details) - USD ($) $ in Thousands		Dec. 31, 2024	Dec. 31, 2023
Schedule of Regulatory Assets and Liabilities [Line Items]
Regulatory Assets		$ 101,783	$ 90,694
Regulatory Liabilities
Regulatory Liabilities		64,557	113,021
Income Taxes [Member]
Regulatory Liabilities
Regulatory Liabilities	[1]	27,380	28,188
Cost of Removal [Member]
Regulatory Liabilities
Regulatory Liabilities	[2]	20,595	19,727
Employee Benefit Plans [Member]
Regulatory Liabilities
Regulatory Liabilities	[3]	9,435	1,471
Lawsuit Settlement [Member]
Regulatory Liabilities
Regulatory Liabilities	[4]	5,334	63,635
New Jersey Revenue Taxes [Member]
Regulatory Liabilities
Regulatory Liabilities	[5]	1,813
Income Taxes [Member]
Schedule of Regulatory Assets and Liabilities [Line Items]
Regulatory Assets	[6]	89,825	84,419
Other Regulatory Assets [Member]
Schedule of Regulatory Assets and Liabilities [Line Items]
Regulatory Assets	[7]	$ 11,958	$ 6,275
[1]The 2017 Tax Act reduced the statutory corporate federal income tax rate from 35% to 21%. The tariff rates charged to customers effective prior to 2018 in the Company’s regulated companies include recovery of income taxes at the statutory rate in effect at the time those rates were approved by the respective state public utility commissions. The Company has recorded regulatory liabilities for excess income taxes collected through rates due to the lower income tax rate under the 2017 Tax Act. These regulatory liabilities are overwhelmingly related to utility plant depreciation deduction timing differences, which are subject to Internal Revenue Service (IRS) normalization rules. The IRS rules limit how quickly the excess taxes attributable to accelerated taxes can be returned to customers. The current base rates for Middlesex and Pinelands customers became effective after 2017 and reflect the impact of the 2017 Tax Act.[2]The Company uses composite depreciation rates for its regulated utility assets, which is currently an acceptable method under GAAP and is widely used in the utility industry. Historically, under the composite depreciation method, the anticipated costs of removing assets upon retirement are provided for over the life of those assets as a component of depreciation expense. The Company recovers certain asset retirement costs through rates charged to customers as an approved component of depreciation expense.[3]Retirement benefits include pension and other retirement benefits that have been recorded on the Consolidated Balance Sheet in accordance with the guidance provided in ASC 715, Compensation – Retirement Benefits

Income Taxes - Schedule of Inco

Income Taxes - Schedule of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule of Income Tax Expense Benefit [Abstract]
Income Tax at Statutory Rate	$ 10,764	$ 6,839	$ 9,590
Tax Effect of:
Utility Plant Related	(659)	(1,495)	(1,106)
Tangible Property Repairs	(4,535)	(5,475)	(6,767)
State Income Taxes – Net	1,270	1,117	1,296
Other	65	55	227
Total Income Tax Expense	$ 6,905	$ 1,041	$ 3,240

Income Taxes - Schedule of In_2

Income Taxes - Schedule of Income Tax Expense (Benefit) is Comprised (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Current:
Federal	$ 1,554	$ 2,952	$ 425
State	1,126	1,066	1,381
Deferred:
Federal	3,802	(3,261)	1,242
State	482	348	260
Investment Tax Credits	(59)	(64)	(68)
Total Income Tax Expense	$ 6,905	$ 1,041	$ 3,240

Income Taxes - Schedule of Defe

Income Taxes - Schedule of Deferred Income Taxes Reflect the Net Tax Effect (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Schedule of Deferred Income Taxes Reflect the Net Tax Effect [Abstract]
Utility Plant Related	$ 95,877	$ 84,330
Customer Advances	(3,525)	(3,546)
Employee Benefits	7,888	7,100
Investment Tax Credits	181	240
Other	814	612
Total Accumulated Deferred Income Taxes	$ 101,235	$ 88,736

Commitments and Contingent Li_3

Commitments and Contingent Liabilities (Details) $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($) gal l	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Commitments and Contingent Liabilities [Line Items]
Average purchase of gallons | l	47
Estimated incremental borrowing rate	4.03%
Operating leases, lease expense | $	$ 0.8	$ 0.8	$ 0.8
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Present Value of Lease Payments
Estimated obligation expenditure | $	$ 9.6
Purchase Commitment [Member]
Commitments and Contingent Liabilities [Line Items]
Purchase commitment expiration date of contract	Nov. 30, 2048
Water Supply [Member]
Commitments and Contingent Liabilities [Line Items]
Average purchase of gallons | gal	27,000,000
NJBPU-Regulated Water [Member]
Commitments and Contingent Liabilities [Line Items]
Purchase commitment expiration date of contract	Feb. 27, 2026
Average purchase of gallons | l	3
Treated Water [Member]
Commitments and Contingent Liabilities [Line Items]
Average purchase of gallons | gal	75,000,000

Commitments and Contingent Li_4

Commitments and Contingent Liabilities - Schedule of Purchased Water Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule of Purchased Water Costs [Abstract]
Untreated	$ 3.5	$ 3.2	$ 3.2
Treated	4	5.3	3.9
Total Costs	$ 7.5	$ 8.5	$ 7.1

Commitments and Contingent Li_5

Commitments and Contingent Liabilities - Schedule of Operating Lease ROU Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Schedule of Operating Lease ROU Assets [Abstract]
ROU Asset at Lease Inception	$ 7,300	$ 7,300
Accumulated Amortization	(4,700)	(4,100)
Current ROU Asset	$ 2,567	$ 3,185

Commitments and Contingent Li_6

Commitments and Contingent Liabilities - Schedule of Future Minimum Operating Lease Commitments (Details) $ in Millions	Dec. 31, 2024 USD ($)
Schedule of Future Minimum Operating Lease Commitments [Abstract]
2025	$ 0.8
2026	0.8
2027	0.9
2028	0.9
2029	0.9
Total Lease Payments	4.3
Imputed Interest	(1.3)
Present Value of Lease Payments	3
Less Current Portion	(0.6)	[1]
Non-Current Lease Liability	$ 2.4
[1]Included in Other Current Liabilities

Short-Term Borrowings (Details)

Short-Term Borrowings (Details) $ in Millions	Dec. 31, 2024 USD ($)
Short-Term Borrowings [Abstract]
Lines of credit	$ 140

Short-Term Borrowings - Schedul

Short-Term Borrowings - Schedule of Short-Term Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Short-Term Borrowings [Abstract]
Average Amount Outstanding	$ 38,700	$ 35,700
Weighted Average Interest Rate	6.33%	6.13%
Notes Payable at Year-End	$ 23,000	$ 42,750
Weighted Average Interest Rate at Year-End	5.63%	6.50%

Short-Term Borrowings - Sched_2

Short-Term Borrowings - Schedule of Lines of Credit (Details) $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($)
Schedule of Lines of Credit [Line Items]
Outstanding	$ 23
Available	117
Maximum	140
Bank of America [Member]
Schedule of Lines of Credit [Line Items]
Outstanding
Available	60
Maximum	$ 60
Credit Type	Uncommitted
Expiration Date	Jan. 23, 2026
PNC Bank [Member]
Schedule of Lines of Credit [Line Items]
Outstanding	$ 23
Available	45
Maximum	$ 68
Credit Type	Committed
Expiration Date	Jan. 31, 2027
CoBank, ACB (CoBank) [Member]
Schedule of Lines of Credit [Line Items]
Outstanding
Available	12
Maximum	$ 12
Credit Type	Committed
Expiration Date	May 20, 2026

Capitalization (Details)

Capitalization (Details) - USD ($)					1 Months Ended			12 Months Ended
	May 31, 2024	May 31, 2023	Apr. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Apr. 30, 2023	May 31, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Jul. 31, 2023
Capitalization [Line Items]
Investment plan								$ 700,000
Sale of stock units (in Shares)						1,000,000
Preferred stock outstanding (in Shares)								16,000	20,000
Convertible preferred stock no par value (in Dollars per share)								$ 7
Preferred stock converted into common shares (in Shares)								51,300
SRF loan amount								$ 140,000,000
Expected maturity date					2044 years
Remaining availability of funds for borrowing								$ 117,000,000
Maturity date							Aug. 01, 2056
Long term debt term								5 years
Convertible preferred stock (in Dollars per share)								$ 7
Carrying amount								$ 129,602,000	$ 133,374,000
Advances for construction carrying amount								22,600,000	$ 21,300,000
Long-Term Debt [Member]
Capitalization [Line Items]
Drawn amount								4,900,000
SRF Loans [Member]
Capitalization [Line Items]
Drawn amount								$ 100,000
CoBank [Member]
Capitalization [Line Items]
Percentage of interest rate											6.17%
All Long Term Debt [Member]
Capitalization [Line Items]
Weighted average interest rate								3.64%	3.65%
Long-Term Debt [Member]
Capitalization [Line Items]
Carrying amount								$ 229,800,000	$ 231,300,000
Delaware SRF Loans [Member]
Capitalization [Line Items]
Remaining availability of funds for borrowing								8,300,000
Minimum [Member]
Capitalization [Line Items]
Percentage of interest rate							2.70%
Maximum [Member]
Capitalization [Line Items]
Percentage of interest rate							3%
New Jersey Infrastructure Bank [Member]
Capitalization [Line Items]
Drawn amount								$ 300,000,000
Tidewater [Member]
Capitalization [Line Items]
SRF loan amount	$ 5,600,000
Interest rates, percentage	2%
Percentage of interest rate			2%			2%
Interest, percentage		5.71%
Borrowed loan			$ 6,900,000
Pinelands Water [Member]
Capitalization [Line Items]
Loan amount		$ 20,000,000									$ 3,900,000
Pinelands Wastewater [Member]
Capitalization [Line Items]
Loan amount											$ 3,600,000
FMB [Member]
Capitalization [Line Items]
Mortgage amount issued							$ 52,200,000
Series 2022A [Member]
Capitalization [Line Items]
Mortgage amount designated							16,200,000
Series 2022B [Member]
Capitalization [Line Items]
Mortgage amount designated							$ 36,000,000
Common Stock [Member]
Capitalization [Line Items]
Granted shares (in Shares)								7,570	4,608	2,664
Preferred Stock [Member]
Capitalization [Line Items]
Issuance of common stock								$ 400,000
Preferred stock authorized (in Shares)								120,000
Preferred stock outstanding (in Shares)									16,000
Preferred stock dividends
Investment Plan 2024 [Member] | Common Stock [Member]
Capitalization [Line Items]
Issuance of common stock								$ 1,000,000
Outside Director Stock Compensation Plan [Member]
Capitalization [Line Items]
Maximum number of shares authorized for grant (in Shares)								100,000
Shares remain available for future awards (in Shares)								34,283
State Revolving Fund [Member]
Capitalization [Line Items]
Drawn amount								$ 1,700,000
SRF loan amount					$ 2,200,000
Interest rates, percentage					0%
Private Placement FMB [Member]
Capitalization [Line Items]
Interest, percentage				5.24%
Proceeds from private placement				$ 40,000,000
Convertible Preferred Stock [Member]
Capitalization [Line Items]
Preferred stock outstanding (in Shares)								5,000	10,000
Convertible preferred stock per shares (in Dollars per share)								$ 7
Issuance of common stock (in Shares)								4,275
Outstanding convertible stock, percentage								10%

Capitalization - Schedule of Lo

Capitalization - Schedule of Long-Term Debt (Details) - Long-Term Debt [Member] $ in Millions	Dec. 31, 2024 USD ($)
Capitalization - Schedule of Long-Term Debt (Details) [Line Items]
2025	$ 7.7
2026	7.5
2027	7.3
2028	7
2029	6.5
Thereafter	$ 323.4

Capitalization - Schedule of Ba

Capitalization - Schedule of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule of Basic and Diluted Earnings Per Share [Line Items]
Net Income	$ 8,804	$ 14,319	$ 10,546	$ 10,682	$ 5,765	$ 9,990	$ 9,901	$ 5,868	$ 44,351	$ 31,524	$ 42,429
Net Income (in Shares)									17,842	17,732	17,597
Preferred Dividend									$ (112)	$ (120)	$ (120)
Earnings Applicable to Common Stock									$ 44,239	$ 31,404	$ 42,309
Earnings Applicable to Common Stock (in Shares)									17,842	17,732	17,597
Basic EPS (in Dollars per share)	$ 0.49	$ 0.8	$ 0.59	$ 0.6	$ 0.32	$ 0.56	$ 0.56	$ 0.33	$ 2.48	$ 1.77	$ 2.4
Diluted:
Earnings Applicable to Common Stock									$ 44,239	$ 31,404	$ 42,309
Earnings Applicable to Common Stock (in Shares)									17,842	17,732	17,597
Convertible Preferred $7.00 Series Dividend									$ 46	$ 67	$ 67
Convertible Preferred $7.00 Series Dividend (in Shares)	104				115				104	115	115
Adjusted Earnings Applicable to Common Stock									$ 44,285	$ 31,471	$ 42,376
Adjusted Earnings Applicable to Common Stock (in Shares)									17,946	17,847	17,712
Diluted EPS (in Dollars per share)	$ 0.49	$ 0.8	$ 0.59	$ 0.59	$ 0.32	$ 0.56	$ 0.55	$ 0.33	$ 2.47	$ 1.76	$ 2.39

Capitalization - Schedule of _2

Capitalization - Schedule of Basic and Diluted Earnings Per Share (Parentheticals) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule of Basic and Diluted Earnings Per Share [Line Items]
Preferred Series Dividend	$ 7	$ 7	$ 7

Capitalization - Schedule of Ca

Capitalization - Schedule of Carrying Amount and Fair Value of the Bonds (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Schedule of Carrying Amount and Fair Value of the FMBs [Abstract]
Carrying Amount	$ 129,602	$ 133,374
Fair Value	$ 125,067	$ 131,745

Employee Benefit Plans (Details

Employee Benefit Plans (Details) $ in Millions	12 Months Ended
	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($) shares	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Employee Benefit Plans [Line Items]
Pension plan		$ 80.8	$ 83.7
Benefits plan assumed annual rate		8%
Increase declining annual rate		0.15%
Capital cost of covered healthcare benefits		5%
Employees plan		1,000
Contributions plan rate		100%
Stock based compensation remain award rate		1%
Compensation plus rate		50%
Contributions exceeding rate		1%
Matching contributions, percent		6%
Matching contributions		$ 0.8	0.8	$ 0.7
Discretionary contribution		$ 1.1	$ 0.9	$ 0.9
Compensation eligible rate		5%
Number of shares authorized (in Shares) | shares		300,000
Percentage of shares available for issuance		70%
Pension Plan [Member]
Employee Benefit Plans [Line Items]
Other benefits plan cash contributions		$ 2.8
Other Postretirement Benefits Plan [Member]
Employee Benefit Plans [Line Items]
Other benefits plan cash contributions		$ 0.9
Forecast [Member] | Pension Plan [Member]
Employee Benefit Plans [Line Items]
Other benefits plan cash contributions	$ 0.9
Forecast [Member] | Other Postretirement Benefits Plan [Member]
Employee Benefit Plans [Line Items]
Other benefits plan cash contributions	$ 1

Employee Benefit Plans - Schedu

Employee Benefit Plans - Schedule of Employee Retirement Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pension Plan [Member]
Schedule of Employee Retirement Benefit Plans [Line Items]
Beginning Balance	$ 91,853	$ 87,788
Service Cost	1,270	1,551	$ 2,362
Interest Cost	4,280	4,270	3,042
Actuarial (Gain) Loss	(5,478)	1,966
Benefits Paid	(4,424)	(3,722)
Ending Balance	87,501	91,853	87,788
Other Benefits Plan [Member]
Schedule of Employee Retirement Benefit Plans [Line Items]
Beginning Balance	28,000	32,909
Service Cost	320	391	799
Interest Cost	1,313	1,608	1,325
Actuarial (Gain) Loss	(486)	(5,968)
Benefits Paid	(946)	(940)
Ending Balance	$ 28,201	$ 28,000	$ 32,909

Employee Benefit Plans - Sche_2

Employee Benefit Plans - Schedule of Change in Fair Value of Plan Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Pension Plan [Member]
Schedule of Change in Fair Value of Plan Assets [Line Items]
Beginning Balance	$ 92,346	$ 84,828
Actual Return on Plan Assets	7,976	10,840
Employer Contributions	2,750	400
Benefits Paid	(4,424)	(3,722)
Ending Balance	98,648	92,346
Funded Status	11,147	494
Other Benefits Plan [Member]
Schedule of Change in Fair Value of Plan Assets [Line Items]
Beginning Balance	48,352	44,029
Actual Return on Plan Assets	4,675	4,323
Employer Contributions	946	940
Benefits Paid	(946)	(940)
Ending Balance	53,027	48,352
Funded Status	$ 24,826	$ 20,352

Employee Benefit Plans - Sche_3

Employee Benefit Plans - Schedule of Employee Benefit Plans Recognized in Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Pension Plan [Member]
Schedule of Employee Benefit Plans Recognized in Balance Sheet [Line Items]
Current Liability	$ 883	$ 933
Noncurrent Asset	(12,030)	(1,427)
Net Asset Recognized	(11,147)	(494)
Other Benefits Plan [Member]
Schedule of Employee Benefit Plans Recognized in Balance Sheet [Line Items]
Current Liability
Noncurrent Asset	(24,826)	(20,352)
Net Asset Recognized	$ (24,826)	$ (20,352)

Employee Benefit Plans - Sche_4

Employee Benefit Plans - Schedule of Components of Net Benefit Cost (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pension Plan [Member]
Schedule of Components of Net Benefit Cost [Line Items]
Service Cost		$ 1,270	$ 1,551	$ 2,362
Interest Cost		4,280	4,270	3,042
Expected Return on Plan Assets		(6,322)	(5,865)	(7,041)
Amortization of Net Actuarial Loss (Gain)		153	658	1,674
Net Periodic Benefit Cost	[1]	(619)	614	37
Other Benefits Plan [Member]
Schedule of Components of Net Benefit Cost [Line Items]
Service Cost		320	391	799
Interest Cost		1,313	1,608	1,325
Expected Return on Plan Assets		(3,384)	(3,082)	(3,547)
Amortization of Net Actuarial Loss (Gain)		(1,098)	(191)
Net Periodic Benefit Cost	[1]	$ (2,849)	$ (1,274)	$ (1,423)
[1]Service cost is included in Operations and Maintenance expense on the consolidated statements of income; all other amounts are included in Other Income, net.

Employee Benefit Plans - Sche_5

Employee Benefit Plans - Schedule of Regulatory Assets into Net Periodic Benefit Cost (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)
Pension Plan [Member]
Schedule of Regulatory Assets into Net Periodic Benefit Cost [Line Items]
Actuarial Loss (Gain)	$ 50
Other Benefits Plan [Member]
Schedule of Regulatory Assets into Net Periodic Benefit Cost [Line Items]
Actuarial Loss (Gain)	$ (1,127)

Employee Benefit Plans - Sche_6

Employee Benefit Plans - Schedule of Discount and Compensation Rates (Details)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pension Plan [Member]
Weighted Average Assumptions:
Expected Return on Plan Assets	7%	7%	7%
Discount Rate for:
Benefit Obligation	5.47%	4.79%	4.98%
Benefit Cost	4.79%	4.98%	2.72%
Compensation Increase for:
Benefit Obligation	3%	3%	3%
Benefit Cost	3%	3%	3%
Other Benefits Plan [Member]
Weighted Average Assumptions:
Expected Return on Plan Assets	7%	7%	7%
Discount Rate for:
Benefit Obligation	5.49%	4.79%	4.98%
Benefit Cost	4.79%	4.98%	2.72%
Compensation Increase for:
Benefit Obligation	3%	3%	3%
Benefit Cost	3%	3%	3%

Employee Benefit Plans - Sche_7

Employee Benefit Plans - Schedule of Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)
Schedule of Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract]
Effect on Current Year Service and Interest Costs	$ 228
Effect on Current Year Service and Interest Costs	(184)
Effect on Projected Benefit Obligation	3,434
Effect on Projected Benefit Obligation	$ (2,824)

Employee Benefit Plans - Sche_8

Employee Benefit Plans - Schedule of Expected Benefit Payments (Details) $ in Thousands	Dec. 31, 2024 USD ($)
Pension Plan [Member]
Schedule of Expected Benefit Payments [Line Items]
2025	$ 5,412
2026	5,399
2027	5,479
2028	5,595
2029	5,581
2030-2034	29,746
Totals	57,212
Other Benefits Plan [Abstract]
Schedule of Expected Benefit Payments [Line Items]
2025	1,303
2026	1,368
2027	1,410
2028	1,444
2029	1,541
2030-2034	8,682
Totals	$ 15,748

Employee Benefit Plans - Sche_9

Employee Benefit Plans - Schedule of Allocation of Plan Assets (Details)	Dec. 31, 2024	Dec. 31, 2023
Pension Plan [Member]
Schedule of Allocation of Plan Assets [Line Items]
Pension Plan	100%	100%
Other Benefits Plan
Other Benefits Plan [Member]
Schedule of Allocation of Plan Assets [Line Items]
Pension Plan	100%	100%
Other Benefits Plan
Equity Securities [Member] | Pension Plan [Member]
Schedule of Allocation of Plan Assets [Line Items]
Pension Plan	31.80%	58.10%
Other Benefits Plan	30%
Equity Securities [Member] | Other Benefits Plan [Member]
Schedule of Allocation of Plan Assets [Line Items]
Pension Plan	65.20%	60.90%
Other Benefits Plan	43%
Debt Securities [Member] | Pension Plan [Member]
Schedule of Allocation of Plan Assets [Line Items]
Pension Plan	67.90%	39.60%
Other Benefits Plan	68%
Debt Securities [Member] | Other Benefits Plan [Member]
Schedule of Allocation of Plan Assets [Line Items]
Pension Plan	33%	36.10%
Other Benefits Plan	50%
Cash [Member] | Pension Plan [Member]
Schedule of Allocation of Plan Assets [Line Items]
Pension Plan	0.30%	0.70%
Other Benefits Plan	2%
Cash [Member] | Other Benefits Plan [Member]
Schedule of Allocation of Plan Assets [Line Items]
Pension Plan	1.80%	3%
Other Benefits Plan	2%
Real Estate/Commodities [Member] | Pension Plan [Member]
Schedule of Allocation of Plan Assets [Line Items]
Pension Plan	0%	1.60%
Other Benefits Plan	0%
Real Estate/Commodities [Member] | Other Benefits Plan [Member]
Schedule of Allocation of Plan Assets [Line Items]
Pension Plan	0%	0%
Other Benefits Plan	5%

Employee Benefit Plans - Sch_10

Employee Benefit Plans - Schedule of Fair Value of Plan Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pension Plan [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	$ 98,648	$ 92,346	$ 84,828
Pension Plan [Member] | Level 1 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	98,648	92,346
Pension Plan [Member] | Level 2 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Pension Plan [Member] | Level 3 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Other Benefits Plan [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	53,027	48,352
Other Benefits Plan [Member] | Level 1 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	35,522	30,866
Other Benefits Plan [Member] | Level 2 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	17,505	17,486
Other Benefits Plan [Member] | Level 3 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Mutual Funds [Member] | Pension Plan [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	31,187	71,236
Mutual Funds [Member] | Pension Plan [Member] | Level 1 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	31,187	71,236
Mutual Funds [Member] | Pension Plan [Member] | Level 2 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Mutual Funds [Member] | Pension Plan [Member] | Level 3 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Mutual Funds [Member] | Other Benefits Plan [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	34,545	29,437
Mutual Funds [Member] | Other Benefits Plan [Member] | Level 1 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	34,545	29,437
Mutual Funds [Member] | Other Benefits Plan [Member] | Level 2 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Mutual Funds [Member] | Other Benefits Plan [Member] | Level 3 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Money Market Funds [Member] | Pension Plan [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	293	663
Money Market Funds [Member] | Pension Plan [Member] | Level 1 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	293	663
Money Market Funds [Member] | Pension Plan [Member] | Level 2 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Money Market Funds [Member] | Pension Plan [Member] | Level 3 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Money Market Funds [Member] | Other Benefits Plan [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	977	1,429
Money Market Funds [Member] | Other Benefits Plan [Member] | Level 1 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	977	1,429
Money Market Funds [Member] | Other Benefits Plan [Member] | Level 2 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Money Market Funds [Member] | Other Benefits Plan [Member] | Level 3 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Common Equity Securities [Member] | Pension Plan [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	195	12,544
Common Equity Securities [Member] | Pension Plan [Member] | Level 1 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	195	12,544
Common Equity Securities [Member] | Pension Plan [Member] | Level 2 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Common Equity Securities [Member] | Pension Plan [Member] | Level 3 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Corporate Bonds [Member] | Pension Plan [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	42,974	5,091
Corporate Bonds [Member] | Pension Plan [Member] | Level 1 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	42,974	5,091
Corporate Bonds [Member] | Pension Plan [Member] | Level 2 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Corporate Bonds [Member] | Pension Plan [Member] | Level 3 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Agency/US/State/Municipal Debt [Member] | Pension Plan [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	19,041	1,854
Agency/US/State/Municipal Debt [Member] | Pension Plan [Member] | Level 1 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	19,041	1,854
Agency/US/State/Municipal Debt [Member] | Pension Plan [Member] | Level 2 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Agency/US/State/Municipal Debt [Member] | Pension Plan [Member] | Level 3 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Agency/US/State/Municipal Debt [Member] | Other Benefits Plan [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	17,505	17,486
Agency/US/State/Municipal Debt [Member] | Other Benefits Plan [Member] | Level 1 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Agency/US/State/Municipal Debt [Member] | Other Benefits Plan [Member] | Level 2 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	17,505	17,486
Agency/US/State/Municipal Debt [Member] | Other Benefits Plan [Member] | Level 3 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Sovereign/Non-US Debt [Member] | Pension Plan [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	4,958	958
Sovereign/Non-US Debt [Member] | Pension Plan [Member] | Level 1 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets	4,958	958
Sovereign/Non-US Debt [Member] | Pension Plan [Member] | Level 2 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets
Sovereign/Non-US Debt [Member] | Pension Plan [Member] | Level 3 [Member]
Schedule of Fair Value of Plan Assets [Line Items]
Fair value of plan assets

Employee Benefit Plans - Sch_11

Employee Benefit Plans - Schedule of Table Presents Awarded but not Yet Vested Share (Details) - Restricted Stock [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule of Table Presents Awarded but not Yet Vested Share [Line Items]
Shares, Balance	74	77	83
Unearned Compensation, Balance (in Dollars)	$ 1,043	$ 1,732	$ 1,931
Shares, Granted	19	15	11
Unearned Compensation, Granted (in Dollars)	$ 1,003	$ 1,165	$ 1,151
Weighted Average Granted Price, Granted (in Dollars per share)	$ 52.5	$ 77.63	$ 105.17
Shares, Vested	(58)	(18)	(17)
Unearned Compensation, Vested (in Dollars)
Shares, Amortization of Compensation expense
Unearned Compensation, Amortization of Compensation expense (in Dollars)	$ (1,140)	$ (1,854)	$ (1,350)
Shares, Balance	35	74	77
Unearned Compensation, Balance (in Dollars)	$ 906	$ 1,043	$ 1,732

Business Segment Data (Details)

Business Segment Data (Details)	12 Months Ended
	Dec. 31, 2024 Segments
Business Segment Data [Abstract]
Reportable segment	2

Business Segment Data - Schedul

Business Segment Data - Schedule of Inter-Segment Transactions (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Revenues:
Consolidated Revenues									$ 191,877	$ 166,274	$ 162,434
Purchased Water:
Consolidated Purchased Water									7,497	8,481	7,089
Other Operations and Maintenance Expenses:
Consolidated Other Operations and Maintenance Expenses									84,866	74,632	72,007
Other Taxes:
Consolidated Other Taxes									21,874	18,744	18,208
Depreciation:
Consolidated Depreciation									24,430	25,194	23,029
Operating Income:
Consolidated Operating Income	$ 10,529	$ 17,501	$ 15,315	$ 9,865	$ 8,242	$ 12,822	$ 10,669	$ 7,490	53,210	39,223	47,333
Other Income (Expense), Net:
Consolidated Other Income (Expense), Net									12,069	6,485	7,703
Interest Expense:
Consolidated Interest Expense									14,023	13,143	9,367
Income Taxes:
Consolidated Income Taxes									6,905	1,041	3,240
Net Income:
Net Income	8,804	$ 14,319	$ 10,546	$ 10,682	5,765	$ 9,990	$ 9,901	$ 5,868	44,351	31,524	42,429
Capital Expenditures:
Total Capital Expenditures									74,622	90,179	91,335
Assets:
Consolidated Assets	1,255,174				1,236,052				1,255,174	1,236,052
Regulated [Member]
Revenues:
Consolidated Revenues									179,359	154,617	151,117
Purchased Water:
Consolidated Purchased Water									8,064	9,144	7,777
Other Operations and Maintenance Expenses:
Consolidated Other Operations and Maintenance Expenses									76,483	66,670	64,170
Other Taxes:
Consolidated Other Taxes									21,644	18,504	17,963
Depreciation:
Consolidated Depreciation									24,173	24,931	22,783
Operating Income:
Consolidated Operating Income									49,462	35,820	44,257
Other Income (Expense), Net:
Consolidated Other Income (Expense), Net									12,195	6,637	7,898
Interest Expense:
Consolidated Interest Expense									14,430	13,508	9,833
Income Taxes:
Consolidated Income Taxes									5,653	(146)	2,084
Net Income:
Net Income									41,575	29,094	40,229
Capital Expenditures:
Total Capital Expenditures									74,584	90,047	91,054
Assets:
Consolidated Assets	1,264,472				1,235,549				1,264,472	1,235,549
Non – Regulated [Member]
Revenues:
Consolidated Revenues									13,552	12,773	12,446
Purchased Water:
Consolidated Purchased Water
Other Operations and Maintenance Expenses:
Consolidated Other Operations and Maintenance Expenses									8,850	8,415	8,278
Other Taxes:
Consolidated Other Taxes									230	240	245
Depreciation:
Consolidated Depreciation									257	263	246
Operating Income:
Consolidated Operating Income									3,748	3,403	3,076
Other Income (Expense), Net:
Consolidated Other Income (Expense), Net									281	214	279
Interest Expense:
Consolidated Interest Expense											7
Income Taxes:
Consolidated Income Taxes									1,252	1,187	1,156
Net Income:
Net Income									2,776	2,430	2,200
Capital Expenditures:
Total Capital Expenditures									38	132	281
Assets:
Consolidated Assets	7,671				8,068				7,671	8,068
Inter-segment Elimination [Member]
Revenues:
Consolidated Revenues									(1,034)	(1,116)	(1,129)
Purchased Water:
Consolidated Purchased Water									(567)	(663)	(688)
Other Operations and Maintenance Expenses:
Consolidated Other Operations and Maintenance Expenses									(467)	(453)	(441)
Other Income (Expense), Net:
Consolidated Other Income (Expense), Net									(407)	(366)	(474)
Interest Expense:
Consolidated Interest Expense									(407)	(365)	$ (473)
Assets:
Consolidated Assets	$ (16,969)				$ (7,565)				$ (16,969)	$ (7,565)

Quarterly Data - Unaudited - Sc

Quarterly Data - Unaudited - Schedule of Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule of Financial Information [Line Items]
Operating Revenues (in Dollars)	$ 47,107	$ 55,100	$ 49,146	$ 40,524	$ 38,602	$ 46,715	$ 42,801	$ 38,156	$ 191,877	$ 166,274
Operating Income (in Dollars)	10,529	17,501	15,315	9,865	8,242	12,822	10,669	7,490	53,210	39,223	$ 47,333
Net Income (in Dollars)	$ 8,804	$ 14,319	$ 10,546	$ 10,682	$ 5,765	$ 9,990	$ 9,901	$ 5,868	$ 44,351	$ 31,524	$ 42,429
Basic Earnings per Share	$ 0.49	$ 0.8	$ 0.59	$ 0.6	$ 0.32	$ 0.56	$ 0.56	$ 0.33	$ 2.48	$ 1.77	$ 2.4
Diluted Earnings per Share	0.49	0.8	0.59	0.59	0.32	0.56	0.55	0.33	2.47	1.76	$ 2.39
Common Dividend Per Share	0.34	0.325	0.325	0.325	0.325	0.3125	0.3125	0.3125	$ 1.315	$ 1.2625
Minimum [Member]
Schedule of Financial Information [Line Items]
High/Low Common Stock Price	52.62	52.74	45.84	50.33	61.34	65.37	66.51	72.64
Maximum [Member]
Schedule of Financial Information [Line Items]
High/Low Common Stock Price	$ 69.7	$ 67.59	$ 58.02	$ 64.71	$ 73.47	$ 84.35	$ 84.38	$ 90.56