Electric Plant and Depreciation (Tables)

3 Months Ended

Mar. 31, 2015

Public Utilities Property Plant And Equipment [Abstract]

Schedule of Major Classes of Electric Plant

The major classes of electric plant are as follows:

(In thousands)	March 31, 2015			December 31, 2014
Electric plant:
Transmission plant	$	970,993		$	966,560
Distribution plant		399,361			387,329
General plant		15,604			15,018
Total plant in service		1,385,958			1,368,907
CWIP		79,641			41,222
Total electric plant		1,465,599			1,410,129
Accumulated depreciation		(226,457	)		(220,101	)
Electric plant held for future use		37,118			37,118
Electric plant, net	$	1,276,260		$	1,227,146