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Employee Postretirement Benefits (Tables)

12 Months Ended

Dec. 31, 2022

Retirement Benefits [Abstract]

Schedule of Target and Tactical Allocation of Plan Assets

The following table presents our target asset allocation permitted range along with the actual asset allocation as of December 31, 2022 and 2021:

			Permitted												Actual Allocation
Asset Class			Range												2022						2021
Return Enhancement			35			–			60%						48		%				47		%
Risk Management			40			–			80%						51						50
Alternatives			0			–			20%						1						3
Total															100		%				100		%

Schedule of Allocation of Plan Assets

The following presents the fair value inputs classified within the fair value hierarchy used to measure Pension Plan assets at December 31, 2022 and 2021 and assets measured using the net asset value (NAV) practical expedient:

(in thousands)			Level 1						Level 2						Level 3						NAV						Total
December 31, 2022
Equity Funds			$	124,327					$	—					$	—					$	—					$	124,327
Fixed Income Funds			156,424						—						—						—						156,424
Hybrid Funds			9,756						—						—						—						9,756
U.S. Treasury Securities			19,588						—						—						—						19,588
SEI Energy Debt Collective Fund			—						—						—						3,703						3,703
Total			310,095						—						—						3,703						313,798
December 31, 2021
Equity Funds			149,479						—						—						—						149,479
Fixed Income Funds			184,987						—						—						—						184,987
Hybrid Funds			11,776						—						—						—						11,776
U.S. Treasury Securities			28,173						—						—						—						28,173
SEI Energy Debt Collective Fund			—						—						—						12,797						12,797
Total			$	374,415					$	—					$	—					$	12,797					$	387,212

Schedule of Changes in Projected Benefit Obligations and Changes in Plan Assets

The following table provides a reconciliation of the changes in the fair value of plan assets and the actuarially computed benefit obligation for the years ended December 31, 2022 and 2021 and the funded status of the plans as of December 31, 2022 and 2021:

			Pension Benefits (Pension Plan)												Pension Benefits (ESSRP)												Postretirement Benefits
(in thousands)			2022						2021						2022						2021						2022						2021
Change in Fair Value of Plan Assets:
Fair Value of Plan Assets at January 1			$	387,212					$	360,678					$	—					$	—					$	—					$	—
Actual Return on Plan Assets			(76,485)						32,816						—						—						—						—
Company Contributions			20,000						10,000						2,205						1,562						2,294						2,695
Benefit Payments			(16,930)						(16,282)						(2,205)						(1,562)						(8,173)						(8,385)
Participant Premium Payments			—						—						—						—						5,879						5,690
Fair Value of Plan Assets at December 31			313,797						387,212						—						—						—						—
Change in Benefit Obligation:
Benefit Obligation at January 1			416,697						428,396						46,840						47,894						69,311						70,185
Service Cost			6,576						7,462						195						187						1,338						1,722
Interest Cost			12,344						11,660						1,341						1,228						2,041						1,891
Benefit Payments			(16,930)						(16,282)						(2,205)						(1,562)						(8,172)						(8,385)
Participant Premium Payments			—						—						—						—						5,879						5,690
Plan Amendments			—						—						—						—						—						—
Actuarial Loss			(110,632)						(14,539)						(10,547)						(907)						(20,450)						(1,792)
Benefit Obligation at December 31			308,055						416,697						35,624						46,840						49,947						69,311
Funded Status			$	5,742					$	(29,485)					$	(35,624)					$	(46,840)					$	(49,947)					$	(69,311)
Amounts Recognized in Consolidated Balance Sheet at December 31:
Noncurrent Assets			$	5,742					$	—					$	—					$	—					$	—					$	—
Current Liabilities			—						—						(2,414)						(2,352)						(2,970)						(2,830)
Noncurrent Liabilities and Deferred Credits			—						(29,485)						(33,210)						(44,488)						(46,977)						(66,481)
Net Asset (Liability)			$	5,742					$	(29,485)					$	(35,624)					$	(46,840)					$	(49,947)					$	(69,311)

Schedule of Assumptions Used in Calculating Net Periodic Benefit Cost

The following assumptions were used to determine benefit obligations as of December 31, 2022 and 2021:

			Pension Benefits (Pension Plan)												Pension Benefits (ESSRP)												Postretirement Benefits
			2022						2021						2022						2021						2022						2021
Discount Rate			5.51		%				3.03		%				5.51		%				2.93		%				5.52		%				3.01		%
Long-Term Rate of Compensation Increase(1)			n/a						n/a						3.00		%				3.00		%				n/a						n/a
Participants to Age 39(1)			4.50		%				4.50		%				n/a						n/a						n/a						n/a
Participants Ages 40 to 49(1)			3.50		%				3.50		%				n/a						n/a						n/a						n/a
Participants Age 50 and Older(1)			2.75		%				2.75		%				n/a						n/a						n/a						n/a
Healthcare Cost Immediate Trend Rate			n/a						n/a						n/a						n/a						7.50		%				6.16		%
Healthcare Cost Ultimate Trend Rate			n/a						n/a						n/a						n/a						4.00		%				4.50		%
Year the Rate Reaches the Ultimate Trend Rate			n/a						n/a						n/a						n/a						2048						2038
(1) The estimated rate of compensation increase for 2023 and 2024, as estimated as of December 31, 2022, is equal to 4.00% for all participants, reflecting higher anticipated compensation changes during these years.

The following assumptions were used to determine net periodic benefit cost for the years ended December 31, 2022, 2021 and 2020:

			Pension Benefits (Pension Plan)																		Pension Benefits (ESSRP)																		Postretirement Benefits
			2022						2021						2020						2022						2021						2020						2022						2021						2020
Discount Rate			3.03		%				2.78		%				3.47		%				2.93		%				2.61		%				3.36		%				3.01		%				2.75		%				3.43		%
Long-Term Rate of Return on Plan Assets			6.30		%				6.51		%				6.88		%				n/a						n/a						n/a						n/a						n/a						n/a
Long-Term Rate of Compensation Increase			n/a						n/a						n/a						3.00		%				3.00		%				3.50		%				n/a						n/a						n/a
Participants to Age 39			4.50		%				4.50		%				4.50		%				n/a						n/a						n/a						n/a						n/a						n/a
Participants Ages 40 to 49			3.50		%				3.50		%				3.50		%				n/a						n/a						n/a						n/a						n/a						n/a
Participants Age 50 and Older			2.75		%				2.75		%				2.75		%				n/a						n/a						n/a						n/a						n/a						n/a

Schedule of Net Benefit Costs

The following table lists the components of net periodic benefit cost of our defined benefit pension plans and other postretirement benefits for the years ended December 31, 2022, 2021 and 2020:

			Pension Benefits (Pension Plan)																		Pension Benefits (ESSRP)																		Postretirement Benefits
(in thousands)			2022						2021						2020						2022						2021						2020						2022						2021						2020
Service Cost			$	6,576					$	7,462					$	6,621					$	195					$	187					$	179					$	1,338					$	1,722					$	1,847
Interest Cost			12,344						11,660						13,053						1,341						1,228						1,449						2,041						1,891						2,393
Expected Return on Assets			(23,684)						(22,359)						(22,021)						—						—						—						—						—						—
Amortization of Prior Service Cost			—						—						—						—						—						—						(5,733)						(5,733)						(4,792)
Amortization of Net Actuarial Loss			7,865						10,914						9,144						567						620						434						3,063						3,774						4,310
Net Periodic Benefit Cost			$	3,101					$	7,677					$	6,797					$	2,103					$	2,035					$	2,062					$	709					$	1,654					$	3,758

The following table includes the impact of regulation on the recognition of periodic benefit cost arising from pension and other postretirement benefits for the years ended December 31, 2022, 2021 and 2020:

(in thousands)			2022						2021						2020
Net Periodic Benefit Cost			$	5,913					$	11,366					$	12,617
Net Amount Amortized (Deferred) Due to the Effect of Regulation			1,121						21						(533)
Net Periodic Benefit Cost Recognized			$	7,034					$	11,387					$	12,084

Schedule of Amounts Recognized in Balance Sheet

The following table presents the amounts not yet recognized as components of net periodic benefit cost as of December 31, 2022 and 2021:

			Pension Benefits (Pension Plan)												Pension Benefits (ESSRP)												Postretirement Benefits
(in thousands)			2022						2021						2022						2021						2022						2021
Regulatory Assets (Liabilities):
Unrecognized Prior Service Cost			$	—					$	—					$	—					$	—					$	(8,400)					$	(13,989)
Unrecognized Actuarial Loss			85,367						102,737						979						2,525						3,993						26,852
Net Regulatory Assets (Liabilities)			85,367						102,737						979						2,525						(4,407)						12,863
Accumulated Other Comprehensive Income (Loss):
Unrecognized Prior Service Cost			—						—						—						—						(99)						(242)
Unrecognized Actuarial (Gain) Loss			(1,978)						(1,020)						1,093						10,660						(818)						(160)
Total Accumulated Other Comprehensive Income (Loss)			$	(1,978)					$	(1,020)					$	1,093					$	10,660					$	(917)					$	(402)

Schedule of Expected Benefit Payments

The following reflects anticipated benefit payments to be paid in each of the next five years and in the aggregate for the five year period thereafter under our pension plans and postretirement healthcare plan:

(in thousands)			2023						2024						2025						2026						2027						2028-2032
Projected Pension Plan Benefit Payments			$	18,023					$	18,556					$	19,073					$	19,565					$	20,015					$	106,067
Projected ESSRP Benefit Payments			2,475						2,764						2,702						2,821						2,987						14,507
Projected Postretirement Benefit Payments			2,970						3,090						3,297						3,451						3,495						17,804
Total			$	23,468					$	24,410					$	25,072					$	25,837					$	26,497					$	138,378

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