Area of a real estate property.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 970
-SubTopic 360
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-28(Column A)(Footnote 2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478979/970-360-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 970
-SubTopic 360
-Name Accounting Standards Codification
-Section 30
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478150/970-360-30-2

Commitments and Contingencies - Additional Information (Details) gal in Millions, $ in Millions			6 Months Ended
	Sep. 12, 2025 USD ($)	Apr. 24, 2024 Claim Improvement	Jun. 30, 2026 USD ($)	Feb. 18, 2026 lawsuit	Dec. 31, 2025 USD ($) Customer	Oct. 09, 2025 a	Aug. 14, 2025 a	May 21, 2025 USD ($)	May 09, 2025 a	Jun. 14, 2024 lawsuit	Dec. 20, 2023 lawsuit	Dec. 11, 2023 Standard	Dec. 06, 2023 USD ($)	Nov. 11, 2023 Customer	Nov. 10, 2023 Customer	Apr. 28, 2023 USD ($)	Dec. 05, 2022 USD ($)	Oct. 31, 2022 gal	Feb. 28, 2021 Parcel	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 Agreement
Commitments And Contingencies [Line Items]
Loss contingency, probable loss			$ 12.0
Daily production, number of gallons related to desalinated water \| gal																		6.4
Initial daily production, number of gallons related to desalinated water \| gal																		4.8
Number of dismissed claims \| Claim		1
Settlement payments received			234.0
Total escrow account funds held in law firm			131.0
Maximum amount of settlement 0f general liabilities insurance carriers			9.0
Maximum amount of obligation			7.0
Maximum amount of loss in contingencies			1.0
Regulatory liability			158.0
Litigation Settlement, Amount Awarded From Other Party, Escrow, Transfers			101.0
Cal Am
Commitments And Contingencies [Line Items]
Number of agreements, void \| Agreement																							4
Number of agreements \| Agreement																							5
Number of agreements, valid \| Agreement																							1
Dunbar \| WVPSC
Commitments And Contingencies [Line Items]
Litigation settlement, amount awarded to other party	$ 5.0
Dunbar \| WVAWC
Commitments And Contingencies [Line Items]
Loss contingency, probable loss			5.0
Litigation settlement, proposed maximum pre-tax amount	18.0
Litigation settlement, amount awarded to other party	$ 5.0
Loss contingency, probable loss, net of tax			4.0
West Virginia \| WVAWC
Commitments And Contingencies [Line Items]
Number of customers for whom a precautionary boil water advisory was issued to \| Customer														300
Number of customers who completed claim process \| Customer					594
Natural gas outage inconvenience per household, average amount paid					$ 1,500.0
West Virginia \| Mountaineer Gas Company
Commitments And Contingencies [Line Items]
Number of customer serving (over) \| Customer															220,000
Number of customer affected by loss of natural gas service \| Customer															1,500
West Virginia \| Mountaineer Gas Company and WVAWC
Commitments And Contingencies [Line Items]
Number of pending lawsuits \| lawsuit				4						4
Number of pending lawsuits with answers provided for \| lawsuit											3
Number of recommended operational improvements \| Improvement		3
Monterey \| Cal Am
Commitments And Contingencies [Line Items]
Water supply projected area \| a						2,500	2,600		2,500
Potential condemnation, asset value																				$ 513.0
Potential condemnation, parcels of land \| Parcel																			58
Potential condemnation, number of statutory standards incorrectly applied by agency \| Standard												2
Potential condemnation, offer rejection amount																$ 448.8
Monterey \| Cal Am \| SWRCB
Commitments And Contingencies [Line Items]
Approved cost estimates																					$ 279.0
Aggregate costs			353.0
Allowance for funds used during construction			117.0
Cost cap for proposed facilities, final																	$ 62.0
Cost cap for extraction wells								$ 11.0
Maximum
Commitments And Contingencies [Line Items]
Loss contingency, possible loss			$ 8.0
Maximum \| West Virginia \| WVAWC
Commitments And Contingencies [Line Items]
Natural gas outage inconvenience per household, amount													$ 2,000.0
Maximum \| Monterey \| Cal Am \| SWRCB
Commitments And Contingencies [Line Items]
Approved recovery amount																	$ 123.0					$ 50.0