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

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
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- Definition

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

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Rate and Regulatory Matters (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
	May 31, 2021	Mar. 31, 2021	Sep. 30, 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	$ 31.0	$ 1.1
Delaware Public Service Commission Member \| Tidewater [Member]
Regulatory Liabilities [Line Items]
Approved increase in annual operating revenues				$ 0.6
Pennsylvania Public Utilities Commissio [Member] \| Twin Lakes [Member]
Regulatory Liabilities [Line Items]
Escrow account			$ 1.7