Pension and Other Postretirement Benefit Costs

6 Months Ended

Jun. 30, 2021

Pension and Other Postretirement Benefits Cost (Reversal of Cost) [Abstract]

Schedule of Net Benefit Costs

The following table provides the components of net periodic benefit cost for the pension and other postretirement benefit plans:

	Three Months Ended June 30,								Six Months Ended June 30,
	Pension Benefits				Other Postretirement Benefits				Pension Benefits				Other Postretirement Benefits
In thousands	2021		2020		2021		2020		2021		2020		2021		2020
Service cost	$	1,714	$	1,658	$	56	$	64	$	3,428	$	3,315	$	111	$	128
Interest cost	3,342		4,011		165		223		6,685		8,022		330		446
Expected return on plan assets	(6,099)		(5,496)		—		—		(12,198)		(10,992)		—		—
Amortization of prior service credit	—		—		(117)		(117)		—		—		(234)		(234)
Amortization of net actuarial loss	5,500		4,778		131		142		11,001		9,556		262		285
Net periodic benefit cost	4,457		4,951		235		312		8,916		9,901		469		625
Amount allocated to construction	(743)		(680)		(22)		(23)		(1,469)		(1,348)		(43)		(46)
Net periodic benefit cost charged to expense	3,714		4,271		213		289		7,447		8,553		426		579
Amortization of regulatory balancing account	1,281		1,281		—		—		4,082		4,082		—		—
Net amount charged to expense	$	4,995	$	5,552	$	213	$	289	$	11,529	$	12,635	$	426	$	579

Schedule of Amounts Recognized in Other Comprehensive Income (Loss)

The following table presents amounts recognized in accumulated other comprehensive loss (AOCL) and the changes in AOCL related to non-qualified employee benefit plans:

	Three Months Ended June 30,				Six Months Ended June 30,
In thousands	2021		2020		2021		2020
Beginning balance	$	(12,681)	$	(10,573)	$	(12,902)	$	(10,733)
Amounts reclassified from AOCL:
Amortization of actuarial losses	301		218		602		436
Total reclassifications before tax	301		218		602		436
Tax benefit	(80)		(58)		(160)		(116)
Total reclassifications for the period	221		160		442		320
Ending balance	$	(12,460)	$	(10,413)	$	(12,460)	$	(10,413)