Segment Reporting (tables)

12 Months Ended

Dec. 31, 2013

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment [Table Text Block]

In thousands	Utility		Gas Storage		Other			Total
2013
Operating revenues	$	727,182	$	31,112	$	224		$	758,518
Depreciation and amortization	69,420		6,485		—			75,905
Income from operations	128,066		14,669		11			142,746
Net income	54,920		5,569		49			60,538
Capital expenditures	137,466		1,458		—			138,924
Total assets at December 31, 2013	2,644,367		310,097		16,447			2,970,911
2012
Operating revenues	$	699,862	$	30,520	$	225		$	730,607
Depreciation and amortization	66,545		6,472		—			73,017
Income from operations	128,854		13,226		100			142,180
Net income	54,049		4,521		209			58,779
Capital expenditures	130,151		1,541		337			132,029
Total assets at December 31, 2012	2,505,655		291,568		15,897			2,813,120
2011
Operating revenues	$	801,478	$	26,354	$	223		$	828,055
Depreciation and amortization	63,843		6,161		—			70,004
Income from operations	135,722		9,090		33			144,845
Net income (loss)	59,673		4,101		(730		)	63,044
Capital expenditures	94,049		6,485		—			100,534

Utility Margin [Table Text Block]

In thousands	2013		2012		2011
Utility margin calculation:
Utility operating revenues	$	727,182	$	699,862	$	801,478
Less: Utility cost of gas	373,298		355,335		458,508
Utility margin	$	353,884	$	344,527	$	342,970