Pension and Other Postretirement Benefits (tables)

6 Months Ended

Jun. 30, 2014

General Discussion of Pension and Other Postretirement Benefits [Abstract]

Net Periodic Benefit Cost Components

	Three Months Ended June 30,
							Other Postretirement
	Pension Benefits						Benefits
In thousands	2014			2013			2014			2013
Service cost	$	1,918		$	2,341		$	136		$	179
Interest cost	4,512			4,104			309			286
Expected return on plan assets	(4,886		)	(4,678		)	—			—
Amortization of net actuarial loss	2,580			4,421			46			169
Amortization of prior service costs	56			55			49			49
Net periodic benefit cost	4,180			6,243			540			683
Amount allocated to construction	(1,201		)	(1,801		)	(171		)	(211		)
Amount deferred to regulatory balancing account(1)	(1,123		)	(2,271		)	—			—
Net amount charged to expense	$	1,856		$	2,171		$	369		$	472

	Six Months Ended June 30,
							Other Postretirement
	Pension Benefits						Benefits
In thousands	2014			2013			2014			2013
Service cost	$	3,836		$	4,682		$	271		$	358
Interest cost	9,024			8,207			619			572
Expected return on plan assets	(9,772		)	(9,356		)	—			—
Amortization of net actuarial loss	5,160			8,842			92			338
Amortization of prior service costs	112			111			98			98
Net periodic benefit cost	8,360			12,486			1,080			1,366
Amount allocated to construction	(2,402		)	(3,656		)	(341		)	(430		)
Amount deferred to regulatory balancing account(1)	(2,224		)	(4,620		)	—			—
Net amount charged to expense	$	3,734		$	4,210		$	739		$	936

Schedule Of Accumulated Other Comprehensive Income Loss Rollforward [Table Text Block]

	Three Months Ended June 30,						Six Months Ended June 30,
In thousands	2014			2013			2014			2013
Beginning balance	$	(6,193	)	$	(9,058	)	$	(6,358	)	$	(9,291	)
Amounts reclassified from AOCL:
Amortization of prior service costs	(2		)	(2		)	(4		)	(4		)
Amortization of actuarial losses	276			385			551			771
Total reclassifications before tax	274			383			547			767
Tax expense	(108		)	(151		)	(216		)	(302		)
Total reclassifications for the period	166			232			331			465
Ending balance	$	(6,027	)	$	(8,826	)	$	(6,027	)	$	(8,826	)