Regulatory Matters (Details) - USD ($) $ in Millions					80 Months Ended
	Oct. 31, 2023	Aug. 01, 2023	Jul. 31, 2023	Oct. 28, 2022	Dec. 31, 2023
Supply Corporation
Regulatory Matters [Line Items]
Public Utilities Proposed Annual Cost of Service			$ 385.4
Public Utilities Proposed Rate Base			$ 1,320.0
Proposed Return on Equity (as a percent)			15.12%
NEW YORK
Regulatory Matters [Line Items]
Approved Return on Equity (as a percent)					8.70%
Proposed Base Rate Increase	$ 88.0
PENNSYLVANIA
Regulatory Matters [Line Items]
Proposed Base Rate Increase				$ 28.1
Public Utilities Authorized Rate Increase, Amount		$ 23.0