JOINTLY OWNED UTILITY PLANT/COORDINATED SERVICES Schedule of Jointly Owned Utility Plant (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Jointly Owned Utility Plant Interests
Net investment	$ 134,343	[1]
Construction work in progress	7,173
Substations
Jointly Owned Utility Plant Interests
Net investment	31,640	[1]
Construction work in progress	4,455
Lines
Jointly Owned Utility Plant Interests
Net investment	102,703	[1]
Construction work in progress	$ 2,718

[1] Amount represents our investment in jointly held plant, which has been reduced by the ownership interest amounts of other parties.