Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2015

Public Utilities, Property, Plant and Equipment [Abstract]

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

In thousands	2015		2014
Utility plant in service	$	2,745,485	$	2,661,097
Utility construction work in progress	39,288		24,886
Less: Accumulated depreciation	867,377		836,510
Utility plant, net	1,917,396		1,849,473
Non-utility plant in service	296,839		297,295
Non-utility construction work in progress	7,768		9,282
Less: Accumulated depreciation	39,340		34,457
Non-utility plant, net	265,267		272,120
Total property, plant, and equipment	$	2,182,663	$	2,121,593
Capital expenditures in accrued liabilities	$	8,985	$	8,757