PROPERTY, PLANT, AND EQUIPMENT (Details) - Public Service Building - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Sep. 30, 2021
Property, plant, and equipment
Costs incurred for repairs and restorations		$ 93.5
Insurance proceeds received	$ 20.0
Receivable for future insurance recoveries		$ 61.0
Costs included in other operation and maintenance	$ 12.5

Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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-Name Accounting Standards Codification
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-Section S99
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Amount of cash inflow for proceeds from settlement of insurance claim, classified as investing activities. Excludes insurance settlement classified as operating activities.

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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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Amount of other operating expense of regulated operation.

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-SubTopic 10
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Total costs incurred for repairs and restorations to WE's Public Service Building. Includes costs that were capitalized and expensed.

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