Amount of escrow deposit disbursements related to property acquisition in noncash investing or financing transactions.

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The amount of cash received during the period as refunds for the overpayment of taxes.

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Amount of public utility's approved rate increase (decrease) by regulatory agency.

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Rate and Regulatory Matters (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Tidewater [Member]
Regulatory Liabilities [Line Items]
Proceeds from net of tax refunds	$ 0.8
New Jersey Board Of Public Utilities [Member] \| Middlesex [Member]
Regulatory Liabilities [Line Items]
Approved increase in annual operating revenues	1.1
Pennsylvania Public Utilities Commissio [Member] \| Twin Lakes [Member]
Regulatory Liabilities [Line Items]
Escrow account	$ 1.7
Delaware Public Service Commission Member \| Tidewater [Member]
Regulatory Liabilities [Line Items]
Approved increase in annual operating revenues		$ 0.6