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Percent of operating revenues.

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Percent of total assets.

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Percent of voting interest held.

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Amount of allowance for credit loss on accounts receivable.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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Organization, Summary of Significant Accounting Policies and Recent Developments (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Aug. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Organization, Summary Of Significant Accounting Policies And Recent Developments [Line Items]
Percent voting interest		50.00%
Percent of operating revenues		91.00%
Percent of total assets		99.00%
Allowance for doubtful accounts		$ 2.6	$ 2.1
Bad debt expense		0.9	1.1	$ 1.0
Write-offs		$ 0.4	$ 0.5	$ 0.6
Artesian Wastewater Management, Inc [Member]
Organization, Summary Of Significant Accounting Policies And Recent Developments [Line Items]
Percentage of interest acquired	100.00%
Common stock acquired	$ 6.4
Minimum [Member]
Organization, Summary Of Significant Accounting Policies And Recent Developments [Line Items]
Estimated useful lives of non-regulated fixed assets		3 years
Maximum [Member]
Organization, Summary Of Significant Accounting Policies And Recent Developments [Line Items]
Estimated useful lives of non-regulated fixed assets		42 years