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Employee Postretirement Benefits (Tables)

12 Months Ended

Dec. 31, 2021

Retirement Benefits [Abstract]

Schedule of Target and Tactical Allocation of Plan Assets

The permitted range is a guide and will at times not reflect the actual asset allocation due to market conditions, actions of our investment managers and required cash flows to and from the Pension Plan.

The following table presents our target asset allocation permitted range along with the actual asset allocation as of December 31, 2021 and 2020:

			Permitted												Actual Allocation
Asset Class			Range												2021						2020
Return Enhancement			20			–			60%						47		%				58		%
Risk Management			40			–			80%						50						39
Alternatives			0			–			20%						3						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, 2021 and 2020 and assets measured using the net asset value (NAV) practical expedient:

(in thousands)			Level 1						Level 2						Level 3						NAV						Total
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
December 31, 2020
Cash Equivalents			$	4					$	—					$	—					$	—					$	4
Equity Funds			180,169						—						—						—						180,169
Fixed Income Funds			159,556						—						—						—						159,556
Hybrid Funds			11,729						—						—						—						11,729
SEI Energy Debt Collective Fund			—						—						—						9,220						9,220
Total			$	351,458					$	—					$	—					$	9,220					$	360,678

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, 2021 and 2020 and the funded status of the plans as of December 31, 2021 and 2020:

			Pension Benefits (Pension Plan)												Pension Benefits (ESSRP)												Postretirement Benefits
(in thousands)			2021						2020						2021						2020						2021						2020
Change in Fair Value of Plan Assets:
Fair Value of Plan Assets at January 1			$	360,678					$	329,781					$	—					$	—					$	—					$	—
Actual Return on Plan Assets			32,816						35,474						—						—						—						—
Company Contributions			10,000						11,200						1,562						1,505						2,695						2,662
Benefit Payments			(16,282)						(15,777)						(1,562)						(1,505)						(8,385)						(6,694)
Participant Premium Payments			—						—						—						—						5,690						4,032
Fair Value of Plan Assets at December 31			387,212						360,678						—						—						—						—
Change in Benefit Obligation:
Benefit Obligation at January 1			$	428,396					$	384,785					$	47,894					$	43,966					$	70,185					$	71,437
Service Cost			7,462						6,621						187						179						1,722						1,847
Interest Cost			11,660						13,053						1,228						1,449						1,891						2,393
Benefit Payments			(16,282)						(15,777)						(1,562)						(1,505)						(8,385)						(6,694)
Participant Premium Payments			—						—						—						—						5,690						4,032
Plan Amendments			—						—						—						—						—						(3,891)
Actuarial Loss (Gain)			(14,539)						39,714						(907)						3,805						(1,792)						1,061
Benefit Obligation at December 31			$	416,697					$	428,396					$	46,840					$	47,894					$	69,311					$	70,185
Funded Status			$	(29,485)					$	(67,718)					$	(46,840)					$	(47,894)					$	(69,311)					$	(70,185)
Amounts Recognized in Consolidated Balance Sheet at December 31:
Current Liabilities			$	—					$	—					$	(2,352)					$	(1,557)					$	(2,830)					$	(2,826)
Noncurrent Liabilities and Deferred Credits			(29,485)						(67,718)						(44,488)						(46,337)						(66,481)						(67,359)
Total Liabilities			$	(29,485)					$	(67,718)					$	(46,840)					$	(47,894)					$	(69,311)					$	(70,185)

Schedule of Assumptions Used in Calculating Net Periodic Benefit Cost

The following assumptions were used to determine benefit obligations as of December 31, 2021 and 2020:

			Pension Benefits (Pension Plan)												Pension Benefits (ESSRP)												Postretirement Benefits
			2021						2020						2021						2020						2021						2020
Discount Rate			3.03		%				2.78		%				2.93		%				2.61		%				3.01		%				2.75		%
Rate of Increase in Future Compensation			n/a						n/a						3.00		%				3.00		%				n/a						n/a
Participants to Age 39			4.50		%				4.50		%				n/a						n/a						n/a						n/a
Participants Ages 40 to 49			3.50		%				3.50		%				n/a						n/a						n/a						n/a
Participants Age 50 and Older			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						6.16		%				6.44		%
Healthcare Cost Ultimate Trend Rate			n/a						n/a						n/a						n/a						4.50		%				4.50		%
Year the Rate Reaches the Ultimate Trend Rate			n/a						n/a						n/a						n/a						2038						2038

The following assumptions were used to determine net periodic benefit cost for the years ended December 31, 2021, 2020 and 2019:

			Pension Benefits (Pension Plan)																		Pension Benefits (ESSRP)																		Postretirement Benefits
			2021						2020						2019						2021						2020						2019						2021						2020						2019
Discount Rate			2.78		%				3.47		%				4.50		%				2.61		%				3.36		%				4.46		%				2.75		%				3.43		%				4.44		%
Long-Term Rate of Return on Plan Assets			6.51		%				6.88		%				7.25		%				n/a						n/a						n/a						n/a						n/a						n/a
Rate of Increase in Future Compensation			n/a						n/a						n/a						3.00		%				3.50		%				3.40		%				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, 2021, 2020 and 2019:

			Pension Benefits (Pension Plan)																		Pension Benefits (ESSRP)																		Postretirement Benefits
(in thousands)			2021						2020						2019						2021						2020						2019						2021						2020						2019
Service Cost			$	7,462					$	6,621					$	5,491					$	187					$	179					$	418					$	1,722					$	1,847					$	1,286
Interest Cost			11,660						13,053						14,412						1,228						1,449						1,735						1,891						2,393						3,083
Expected Return on Assets			(22,359)						(22,021)						(21,297)						—						—						—						—						—						—
Amortization of Prior Service Cost			—						—						14						—						—						22						(5,733)						(4,792)						—
Amortization of Net Actuarial Loss			10,914						9,144						4,756						620						434						472						3,774						4,310						1,609
Net Periodic Benefit Cost			$	7,677					$	6,797					$	3,376					$	2,035					$	2,062					$	2,647					$	1,654					$	3,758					$	5,978

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, 2021, 2020, 2019:

(in thousands)			2021						2020						2019
Net Periodic Benefit Cost			$	11,366					$	12,617					$	12,001
Net Amount Amortized (Deferred) Due to the Effect of Regulation			21						(533)						(513)
Net Periodic Benefit Cost Recognized			$	11,387					$	12,084					$	11,488

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, 2021 and 2020:

			Pension Benefits (Pension Plan)												Pension Benefits (ESSRP)												Postretirement Benefits
(in thousands)			2021						2020						2021						2020						2021						2020
Regulatory Assets:
Unrecognized Prior Service Cost			$	—					$	—					$	—					$	—					$	(13,989)					$	(19,579)
Unrecognized Actuarial Loss			102,737						137,500						2,525						2,681						26,852						32,238
Total Regulatory Assets			$	102,737					$	137,500					$	2,525					$	2,681					$	12,863					$	12,659
Accumulated Other Comprehensive Loss:
Unrecognized Prior Service Cost			$	—					$	—					$	—					$	1					$	(242)					$	(386)
Unrecognized Actuarial (Gain) Loss			(1,020)						128						10,660						12,030						(160)						21
Total Accumulated Other Comprehensive Loss			$	(1,020)					$	128					$	10,660					$	12,031					$	(402)					$	(365)

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)			2022						2023						2024						2025						2026						2027-2032
Projected Pension Plan Benefit Payments			$	17,200					$	17,860					$	18,428					$	18,947					$	19,427					$	102,905
Projected ESSRP Benefit Payments			1,981						2,570						2,781						2,715						2,828						14,941
Projected Postretirement Benefit Payments			3,001						3,126						3,209						3,324						3,432						17,225
Total			$	22,182					$	23,556					$	24,418					$	24,986					$	25,687					$	135,071

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