Pension and Other Postretirement Plans (Tables)

9 Months Ended

Sep. 30, 2024

Retirement Benefits [Abstract]

Schedule of Net Periodic Benefit Costs

The following table presents the components of net periodic benefit costs recognized.

	Three Months Ended						Nine Months Ended
	September 30,						September 30,
(In thousands)	2024			2023			2024			2023
Pension Benefits
Components of net periodic benefit cost:
Service cost	$	769		$	723		$	2,308		$	2,169
Interest cost		4,280			4,330			12,839			12,989
Expected return on assets		(7,149	)		(6,312	)		(21,448	)		(18,936	)
Amortization of:
Actuarial loss		215			440			644			1,320
Net periodic benefit (credit) cost	$	(1,885	)	$	(819	)	$	(5,657	)	$	(2,458	)
Postretirement Benefits(a)
Components of net periodic benefit cost:
Service cost	$	214		$	195		$	642		$	585
Interest cost		778			827			2,354			2,481
Expected return on assets		(675	)		(649	)		(2,059	)		(1,946	)
Settlement cost		288			—			288			—
Amortization of:
Transition obligation		1			1			2			2
Prior service credit		(234	)		—			(242	)		—
Actuarial loss (gain)		774			(48	)		568			(143	)
Net periodic benefit cost	$	1,146		$	326		$	1,553		$	979

(a)In August 2024, MGE entered into an agreement to transfer the mortality and investment risk, as well as the administration of, its employer-paid life insurance plan to a third party. MGE accounted for the settlement under the scope of ASC 715.