Pension and Other Postretirement Benefits (tables)

6 Months Ended

Jun. 30, 2013

General Discussion of Pension and Other Postretirement Benefits [Abstract]

Net Periodic Benefit Cost Components

	Three Months Ended Three Months Ended June 30,
							Other Postretirement
	Pension Benefits						Benefits
In thousands	2013			2012			2013			2012
Service cost	$	2,341		$	2,130		$	179		$	177
Interest cost	4,104			4,304			286			315
Expected return on plan assets	(4,678		)	(4,639		)	—			—
Amortization of net actuarial loss	4,421			3,844			169			103
Amortization of prior service costs	55			49			49			49
Amortization of transition obligations	—			—			—			103
Net periodic benefit cost	6,243			5,688			683			747
Amount allocated to construction	(1,801		)	(1,428		)	(211		)	(215		)
Amount deferred to regulatory balancing account(1)	(2,271		)	(2,094		)	—			—
Net amount charged to expense	$	2,171		$	2,166		$	472		$	532

	Three Months Ended Six Months Ended June 30,
							Other Postretirement
	Pension Benefits						Benefits
In thousands	2013			2012			2013			2012
Service cost	$	4,682		$	4,260		$	358		$	354
Interest cost	8,207			8,608			572			629
Expected return on plan assets	(9,356		)	(9,277		)	—			—
Amortization of net actuarial loss	8,842			7,687			338			206
Amortization of prior service costs	111			98			98			98
Amortization of transition obligations	—			—			—			206
Net periodic benefit cost	12,486			11,376			1,366			1,493
Amount allocated to construction	(3,656		)	(2,846		)	(430		)	(429		)
Amount deferred to regulatory balancing account(1)	(4,620		)	(4,162		)	—			—
Net amount charged to expense	$	4,210		$	4,368		$	936		$	1,064

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

	Three Months Ended			Six Months Ended
In thousands	June 30, 2013			June 30, 2013
Beginning balance	$	(9,058	)	$	(9,291	)
Amounts reclassified into AOCL	—			—
Amounts reclassified from AOCL:
Amortization of prior service costs	(2		)	(4		)
Amortization of actuarial losses	385			771
Total reclassifications before tax	383			767
Tax expense	(151		)	(302		)
Total reclassifications for the period	232			465
Ending balance	$	(8,826	)	$	(8,826	)