Property, Plant and Equipment (Tables)

9 Months Ended

Sep. 30, 2018

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

Property, plant and equipment consisted of the following:

(in thousands)	Estimated Useful Lives	September 30, 2018		December 31, 2017
Land		$	6,568	$	6,418
Buildings and structures	10 - 40 years	207,647		195,540
Cable and wire	4 - 40 years	302,592		286,999
Equipment and software	2 - 17 years	763,089		730,228
Plant in service		1,279,896		1,219,185
Plant under construction		74,422		62,202
Total property, plant and equipment		1,354,318		1,281,387
Less accumulated amortization and depreciation		684,609		595,060
Property, plant and equipment, net		$	669,709	$	686,327