Abandonment Costs

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- Definition

Abandonment Costs, Amortization Period

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Alternative Revenue, Period Increase (Decrease)

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- Definition

Percent Of Transmission Costs Allocated Between Wholesale And Retail Customers

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Percent Of Transmission Costs Allocated To Retail Customers

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- Definition

Percentage of public utility's approved return on equity.

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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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Percentage of public utility's requested return on equity.

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- Definition

The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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REGULATORY MATTERS (2019 FERC Rate Case) (Details) - USD ($) $ in Thousands		12 Months Ended
	Aug. 01, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Public Utilities, General Disclosures [Line Items]
Wholesale revenue		$ 1,480,000	$ 1,324,000	$ 1,343,000
Regulatory liability		$ 111,356	151,189
Federal Energy Regulatory Commission
Public Utilities, General Disclosures [Line Items]
Percent of transmission costs allocated to retail customers		25.00%
Percent of transmission costs allocated between wholesale and retail customers		75.00%
Abandonment costs		$ 4,000
Abandonment costs, amortization period		10 years
Decrease in alternative revenue		$ 3,000
Federal Energy Regulatory Commission \| Transmission Service
Public Utilities, General Disclosures [Line Items]
Wholesale revenue		$ 12,000	4,000	$ 3,000
Federal Energy Regulatory Commission \| Transmission Services Rate
Public Utilities, General Disclosures [Line Items]
Approved return on equity (percentage)	10.40%
Requested return on equity (percentage)		9.79%
Federal Energy Regulatory Commission \| Transmission Services Rate \| Revenue Subject to Refund
Public Utilities, General Disclosures [Line Items]
Regulatory liability		$ 15,000	$ 15,000