Pension and Other Postretirement Benefit Costs (Tables)

6 Months Ended

Jun. 30, 2020

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	2020			2019			2020			2019			2020			2019			2020			2019
Service cost	$	1,658		$	1,516		$	64		$	67		$	3,315		$	3,033		$	128		$	135
Interest cost	4,011			4,661			223			283			8,022			9,323			446			564
Expected return on plan assets	(5,496		)	(5,207		)	—			—			(10,992		)	(10,414		)	—			—
Amortization of prior service costs	—			2			(117		)	(117		)	—			4			(234		)	(234		)
Amortization of net actuarial loss	4,778			3,603			142			96			9,556			7,206			285			193
Net periodic benefit cost	4,951			4,575			312			329			9,901			9,152			625			658
Amount allocated to construction	(680		)	(596		)	(23		)	(23		)	(1,348		)	(1,182		)	(46		)	(47		)
Net periodic benefit cost charged to expense	4,271			3,979			289			306			8,553			7,970			579			611
Regulatory pension disallowance	—			—			—			—			—			10,500			—			—
Amortization of regulatory balancing account	1,281			1,281			—			—			4,082			13,792			—			—
Net amount charged to expense	$	5,552		$	5,260		$	289		$	306		$	12,635		$	32,262		$	579		$	611

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	2020			2019			2020			2019
Beginning balance	$	(10,573	)	$	(8,439	)	$	(10,733	)	$	(7,188	)
Amounts reclassified from AOCL:
Amortization of actuarial losses	218			156			436			312
Reclassification of stranded tax effects(1)	—			—			—			(1,366		)
Total reclassifications before tax	218			156			436			(1,054		)
Tax (benefit) expense	(58		)	(41		)	(116		)	(82		)
Total reclassifications for the period	160			115			320			(1,136		)
Ending balance	$	(10,413	)	$	(8,324	)	$	(10,413	)	$	(8,324	)

⁽¹⁾

Reclassification of $1.4 million of income tax effects resulting from the TCJA from accumulated other comprehensive loss to retained earnings was made pursuant to the adoption of ASU 2018-02. See Note 2.