Retirement Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2023

Key Weighted Average Assumptions Used in Determining Benefit Plan Costs and Obligations

The following table includes the key assumptions used in determining the Company’s benefit plan costs and obligations:

	2023			2022			2021
Used to Determine Plan costs for years ended December 31:
Discount Rate		5.25	%		2.85	%		2.50	%
Rate of Compensation Increase		3.00	%		3.00	%		3.00	%
Expected Long-term rate of return on plan assets		7.50	%		7.50	%		7.50	%

Used to Determine Benefit Obligations at December 31:
Discount Rate	5.00	%	5.25	%	2.85	%
Rate of Compensation Increase	3.00	%	3.00	%	3.00	%

Components of Retirement Plan Costs

The following table provides the components of the Company’s Retirement plan costs (000’s):

	Pension Plan									PBOP Plan									SERP
	2023			2022			2021			2023			2022			2021			2023			2022			2021
Service Cost	$	2,091		$	3,165		$	3,472		$	1,493		$	2,890		$	3,034		$	250		$	273		$	354
Interest Cost		7,480			5,486			5,003			2,899			3,194			2,740			754			472			458
Expected Return on Plan Assets		(10,689	)		(10,883	)		(9,693	)		(3,408	)		(3,415	)		(2,508	)		—			—			—
Prior Service Cost Amortization		356			356			301			794			1,092			1,208			55			55			56
Actuarial Loss Amortization		—			5,507			8,089			(1,464	)		1,020			1,045			—			794			1,489
Sub-total		(762	)		3,631			7,172			314			4,781			5,519			1,059			1,594			2,357
Amounts Capitalized or Deferred		1,598			(1,085	)		(3,384	)		555			(2,388	)		(3,136	)		(327	)		(472	)		(712	)
NPBC Recognized	$	836		$	2,546		$	3,788		$	869		$	2,393		$	2,383		$	732		$	1,122		$	1,645

Plans' Assets, Projected Benefit Obligations (PBO), and Funded Status

The following table represents information on the plans’ assets, projected benefit obligations (PBO), and funded status (000’s):

	Pension Plan						PBOP Plan						SERP
Change in Plan Assets:	2023			2022			2023			2022			2023			2022
Plan Assets at Beginning of Year	$	126,098		$	152,006		$	44,770		$	42,651		$	—		$	—
Actual Return on Plan Assets		16,822			(19,984	)		6,865			(6,810	)		—			—
Employer Contributions		3,850			3,800			2,790			12,153			665			637
Participant Contributions		—			—			234			279			—			—
Benefits Paid		(8,877	)		(9,724	)		(2,767	)		(3,503	)		(665	)		(637	)
Plan Assets at End of Year	$	137,893		$	126,098		$	51,892		$	44,770		$	—		$	—
Change in PBO:
PBO at Beginning of Year	$	146,953		$	199,418		$	56,510		$	112,087		$	14,810		$	17,714
Service Cost		2,091			3,165			1,493			2,890			250			273
Interest Cost		7,480			5,486			2,899			3,194			754			472
Participant Contributions		—			—			234			279			—			—
Plan Amendments		—			—			—			—			—			—
Benefits Paid		(8,877	)		(9,724	)		(2,767	)		(3,503	)		(665	)		(637	)
Actuarial (Gain) or Loss		6,920			(51,392	)		8,322			(58,437	)		(295	)		(3,012	)
PBO at End of Year	$	154,567		$	146,953		$	66,691		$	56,510		$	14,854		$	14,810
Funded Status: Assets vs PBO	$	(16,674	)	$	(20,855	)	$	(14,799	)	$	(11,740	)	$	(14,854	)	$	(14,810	)

Employer Contributions, Participant Contributions and Benefit Payments

The following table represents employer contributions, participant contributions and benefit payments (000’s).

	Pension Plan						PBOP Plan							SERP
	2023		2022		2021		2023			2022		2021		2023		2022		2021
Employer Contributions	$	3,850	$	3,800	$	4,100	$	2,790		$	12,153	$	8,903	$	665	$	637	$	637
Participant Contributions	$	—	$	—	$	—	$	234		$	279	$	220	$	—	$	—	$	—
Benefit Payments	$	8,877	$	9,724	$	6,489	$	(2,767	)	$	3,503	$	2,905	$	665	$	637	$	637

Estimated Future Benefit Payments

The following table represents estimated future benefit payments (000’s).

Estimated Future Benefit Payments
	Pension		PBOP		SERP
2024	$	8,006	$	3,197	$	679
2025		8,678		3,466		1,173
2026		9,162		3,698		1,167
2027		10,210		3,789		1,160
2028		10,309		3,803		1,153
2029-2033		57,049		20,913		5,607

Pension Plans

Schedule of Allocation of Plan Assets

The actual investment allocations are shown in the following tables.

Pension Plan	Target Allocation			Actual Allocation at December 31,
	2024			2023			2022			2021
Equity Funds		58	%		57	%		53	%		57	%
Debt Funds		37	%		36	%		38	%		38	%
Real Estate Fund		5	%		6	%		7	%		4	%
Other(1)		—			1	%		2	%		1	%
Total					100	%		100	%		100	%

Represents investments being held in cash equivalents as of December 31, 2023, December 31, 2022 and December 31, 2021 pending payment of benefits.

Assets measured at fair value on a recurring basis for the Pension Plan as of December 31, 2023 and 2022 are as follows (000’s):

	Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31,		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
2023
Pension Plan Assets:
Mutual Funds:
Equity Funds	$	78,522	$	78,522	$	—	$	—
Fixed Income Funds		49,359		49,359		—		—
Total Mutual Funds		127,881		127,881		—		—
Cash Equivalents		2,266		2,266
Total Assets in the Fair Value Hierarchy	$	130,147	$	130,147	$	—	$	—
Real Estate Fund–Measured at Net Asset Value		7,746
Total Assets	$	137,893
2022
Pension Plan Assets:
Mutual Funds:
Equity Funds	$	67,332	$	67,332	$	—	$	—
Fixed Income Funds		47,646		47,646		—		—
Total Mutual Funds		114,978		114,978		—		—
Cash Equivalents		2,598		2,598
Total Assets in the Fair Value Hierarchy	$	117,576	$	117,576	$	—	$	—
Real Estate Fund–Measured at Net Asset Value		8,522
Total Assets	$	126,098

Other Postretirement Benefit Plans, Defined Benefit

Schedule of Allocation of Plan Assets

The actual investment allocations are shown in the following tables.

PBOP Plan	Target Allocation			Actual Allocation at December 31,
	2024			2023			2022			2021
Equity Funds		55	%		56	%		55	%		56	%
Debt Funds		45	%		44	%		45	%		44	%
Total					100	%		100	%		100	%

Assets measured at fair value on a recurring basis for the PBOP Plan as of December 31, 2023 and 2022 are as follows (000’s):

	Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31,		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
2023
PBOP Plan Assets:
Mutual Funds:
Fixed Income Funds	$	23,025	$	23,025	$	—	$	—
Equity Funds		28,867		28,867		—		—
Total Assets	$	51,892	$	51,892	$	—	$	—
2022
PBOP Plan Assets:
Mutual Funds:
Fixed Income Funds	$	20,156	$	20,156	$	—	$	—
Equity Funds		24,614		24,614		—		—
Total Assets	$	44,770	$	44,770	$	—	$	—