Deferred Compensation, Maximum Incentive Payments

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- Definition

Deferred Compensation, Maximum Salary

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- Definition

Percentage of service related net periodic benefit costs capitalized to utility property.

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- Definition

Percentage of service related net periodic benefit costs recorded to operating expenses.

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- Definition

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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No definition available.

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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 55
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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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-Publisher FASB
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- Definition

Amount of cash outflow for pension benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes other postretirement benefit.

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-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
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Pension Plans and Other Postretirement Benefit Plans - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Mar. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Payment for pension benefits	$ 22,000	$ 22,000	$ 22,000
Percentage of service related net periodic benefit costs capitalized to utility property	40.00%
Percentage of service related net periodic benefit costs recorded to operating expenses	60.00%
Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member] \| Executive Officer [Member]
Defined Benefit Plan Disclosure [Line Items]
Deferred compensation, earlier of retirement, termination, disability or death, percent	75.00%
Deferred compensation incentive payments, percent	100.00%
Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation	35.00%	35.00%
Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation	49.00%	49.00%
Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation	7.00%	7.00%
Absolute Return [Member]
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation	9.00%	9.00%
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to pension plan	$ 42,000
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to pension plan	$ 6,800
Other Postretirement Benefits [Member] \| Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation	60.00%	60.00%
Other Postretirement Benefits [Member] \| Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation	40.00%	40.00%
Other Postretirement Benefits [Member] \| Forecast [Member] \| Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation				55.00%
Other Postretirement Benefits [Member] \| Forecast [Member] \| Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation				40.00%
Other Postretirement Benefits [Member] \| Forecast [Member] \| Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation				5.00%
Other Postretirement Benefits [Member] \| Forecast [Member] \| Absolute Return [Member]
Defined Benefit Plan Disclosure [Line Items]
Target investment allocation				0.00%