Pension and Other Postretirement Benefits (tables)

12 Months Ended

Dec. 31, 2012

General Discussion of Pension and Other Postretirement Benefits [Abstract]

Schedule of Defined Benefit Plans Disclosures [Table Text Block]

	Postretirement Benefit Plans
	Pension Benefits						Other Benefits
In thousands	2012			2011			2012			2011
Reconciliation of change in benefit obligation:
Obligation at January 1	$	391,127		$	339,338		$	30,049		$	27,676
Service cost	8,047			7,122			592			614
Interest cost	17,295			18,134			1,267			1,404
Net actuarial (gain) or loss	37,615			44,802			3,182			2,225
Benefits paid	(18,195		)	(18,269		)	(1,971		)	(1,870		)
Obligation at December 31	$	435,889		$	391,127		$	33,119		$	30,049
Reconciliation of change in plan assets:
Fair value of plan assets at January 1	$	215,970		$	219,014		$	—		$	—
Actual return on plan assets	26,683			(6,684		)	—			—
Employer contributions	25,145			21,909			1,971			1,870
Benefits paid	(18,195		)	(18,269		)	(1,971		)	(1,870		)
Fair value of plan assets at December 31	$	249,603		$	215,970		$	—		$	—
Funded status at December 31	$	(186,286	)	$	(175,157	)	$	(33,119	)	$	(30,049	)

Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block]

	Regulatory Assets																		Other Comprehensive Income
	Pension Benefits									Other Postretirement Benefits									Pension Benefits
In thousands	2012			2011			2010			2012			2011			2010			2012			2011			2010
Net actuarial loss	$	26,504		$	66,404		$	17,115		$	3,182		$	2,225		$	2,387		$	3,511		$	2,948		$	1,716
Amortization of:
Transition obligation	—			—			—			(411		)	(411		)	(411		)	—			—			—
Prior service cost	(230		)	(230		)	(230		)	(197		)	(197		)	(197		)	35			(122		)	43
Actuarial loss	(14,482		)	(10,731		)	(6,740		)	(435		)	(289		)	(131		)	(1,150		)	(854		)	(707		)
Total	$	11,792		$	55,443		$	10,145		$	2,139		$	1,328		$	1,648		$	2,396		$	1,972		$	1,052

Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]

	Regulatory Assets								AOCI
	Pension Benefits				Other Postretirement Benefits				Pension Benefits
In thousands	2012		2011		2012		2011		2012			2011
Net transition obligation	$	—	$	—	$	—	$	411	$	—		$	—
Prior service cost	1,097		1,328		882		1,079		(12		)	(48		)
Net actuarial loss	188,278		176,255		9,681		6,934		15,327			12,966
Total	$	189,375	$	177,583	$	10,563	$	8,424	$	15,315		$	12,918

Schedule of Allocation of Plan Assets [Table Text Block]

Asset Category	Target Allocation
U.S. large cap equity	13.0	%
U.S. small/mid cap equity	8.5	%
Non-U.S. equity	13.0	%
Emerging markets equity	3.5	%
Long government/credit	30.0	%
High yield	5.0	%
Emerging market debt	5.0	%
Real estate funds	6.0	%
Absolute return strategy	11.0	%
Real return strategy	5.0	%

Net Periodic Benefit Cost Components

	Pension Benefits									Other Postretirement Benefits
In thousands	2012			2011			2010			2012			2011			2010
Service cost	$	8,047		$	7,122		$	6,688		$	592		$	614		$	588
Interest cost	17,295			18,134			18,029			1,267			1,404			1,436
Expected return on plan assets	(19,082		)	(17,867		)	(18,207		)	—			—			—
Amortization of transition obligations	—			—			—			411			411			411
Amortization of prior service costs	195			352			187			197			197			197
Amortization of net actuarial loss	15,631			11,584			7,447			435			289			131
Net periodic benefit cost	22,086			19,325			14,144			2,902			2,915			2,763
Amount allocated to construction	(5,820		)	(4,905		)	(3,729		)	(882		)	(878		)	(904		)
Amount deferred to regulatory balancing account(1)	(7,876		)	(6,008		)	—			—			—			—
Net amount charged to expense	$	8,390		$	8,412		$	10,415		$	2,020		$	2,037		$	1,859

Sensitivity Analysis Of Retirement Benefit Costs and Benefit Obligations [Table Text Block]

	Pension Benefits						Other Postretirement Benefits
	2012		2011		2010		2012		2011		2010
Assumptions for net periodic benefit cost:
Weighted-average discount rate	4.51	%	5.49	%	6.01	%	4.33	%	5.16	%	5.78	%
Rate of increase in compensation	3.25-5.0%		3.25-5.0%		3.25-5.0%		n/a		n/a		n/a
Expected long-term rate of return	8.00	%	8.25	%	8.25	%	n/a		n/a		n/a
Assumptions for year-end funded status:
Weighted-average discount rate	3.85	%	4.51	%	5.49	%	3.56	%	4.33	%	5.16	%
Rate of increase in compensation	3.25-5.0%		3.25-5.0%		3.25-5.0%		n/a		n/a		n/a
Expected long-term rate of return	7.50	%	8.00	%	8.25	%	n/a		n/a		n/a

Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates [Table Text Block]

In thousands	1% Increase		1% Decrease
Effect on net periodic postretirement health care benefit cost	$	65	$	(58	)
Effect on the accumulated postretirement benefit obligation	943		(841		)

Defined Benefit Plan Estimated Future Employer Contributions Benefit Payments and Estimated Future Payments [Table Text Block]

In thousands	Pension Benefits		Other Benefits
Employer Contributions:
2011	$	22,325	$	1,870
2012	25,559		1,971
2013 (estimated)	13,803		2,004
Benefit Payments:
2010	18,645		1,476
2011	18,269		1,870
2012	18,195		1,971
Estimated Future Benefit Payments:
2013	19,732		2,004
2014	20,244		2,080
2015	20,788		2,108
2016	21,490		2,169
2017	22,245		2,213
2018-2022	128,609		11,514

Schedule of Changes in Fair Value of Plan Assets [Table Text Block]

In thousands	December 31, 2012
Investments	Level 1		Level 2		Level 3		Total
U.S. large cap equity	$	29,047	$	1,891	$	—	$	30,938
U.S. small/mid cap equity	21,624		1,312		—		22,936
Non-U.S. equity	13,931		15,812		—		29,743
Emerging markets equity	8,004		—		—		8,004
Fixed income	—		8,824		—		8,824
Long government/credit	30,098		29,249		—		59,347
High yield bonds	—		12,017				12,017
Emerging market debt	11,421		—				11,421
Real estate funds	15,992		—		—		15,992
Absolute return strategy	—		32,078		—		32,078
Real return strategy	12,932		—		—		12,932
Cash and cash equivalents	—		1,459		—		1,459
Total investments	$	143,049	$	102,642	$	—	$	245,691
	December 31, 2011
Investments	Level 1		Level 2		Level 3		Total
U.S. large cap equity	$	36,236	$	—	$	—	$	36,236
U.S. small/mid cap equity	—		27,310		—		27,310
Non-U.S. equity	22,158		11,587		—		33,745
Emerging markets equity	10,208		—		—		10,208
Fixed income	19,121		—		—		19,121
Long government/credit	—		18,897		—		18,897
Real estate funds	—		—		15,317		15,317
Absolute return strategy	—		30,475		—		30,475
Real return strategy	15,475		—		—		15,475
Cash and cash equivalents	—		9,290		—		9,290
Total investments	$	103,198	$	97,559	$	15,317	$	216,074
					December 31,
Receivables					2012		2011
Accrued interest and dividend income					$	388	$	414
Due from broker for securities sold					4,459		321
Total receivables					$	4,847	$	735
Liabilities
Due to broker for securities purchased					$	935	$	839
Total investment in retirement trust					$	249,603	$	215,970

Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets [Table Text Block]

	Level 3 Assets
In thousands	Real Estate Funds
January 1, 2012 balance	$	15,317
Sales	(15,317		)
December 31, 2012 balance	$	—