PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION -Narrative (Details) - USD ($) $ in Millions		12 Months Ended
Jul. 31, 2020	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
After-tax gain (loss) on the sale of property, plant and equipment		$ 3.5
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Hingham Water System
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 63.9
Goodwill	23.6
Proceeds from the sale of Hingham Water System	$ 110.5
Pre-tax gain (loss) on sale of property, plant and equipment		$ 16.0

Gain Loss on Disposition of Property Plant and Equipment Net of Tax

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- Definition

Amount classified as goodwill attributable to disposal group held for sale or disposed of.

+ References

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Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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