Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2016

Public Utilities, Property, Plant and Equipment [Abstract]

Major Classifications Of Property, Plant And Equipment And Accumulated Depreciation [Text Block]

In thousands	2016		2015
Utility plant in service	$	2,843,243	$	2,745,485
Utility construction work in progress	62,264		39,288
Less: Accumulated depreciation	903,096		867,377
Utility plant, net	2,002,411		1,917,396
Non-utility plant in service	299,378		296,839
Non-utility construction work in progress	3,931		7,768
Less: Accumulated depreciation	44,820		39,340
Non-utility plant, net	258,489		265,267
Total property, plant, and equipment	$	2,260,900	$	2,182,663
Capital expenditures in accrued liabilities	$	9,547	$	8,985