Goodwill (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($)
Goodwill [Line Items]
Balance	$ 42,208
Goodwill acquired	72
Reclassification to utility plant acquisition adjustment	(14)
Balance	42,266
Regulated [Member]
Goodwill [Line Items]
Balance	37,367
Goodwill acquired	72
Reclassification to utility plant acquisition adjustment	(14)
Balance	37,425
Other [Member]
Goodwill [Line Items]
Balance	4,841
Goodwill acquired
Reclassification to utility plant acquisition adjustment
Balance	$ 4,841