Rate Matters (Details) - DSIC [Member] - PPUC [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Rate Matters [Abstract]
Distribution system improvement charge revenue	$ 405	$ 0	$ 467	$ 0
Maximum [Member]
Rate Matters [Abstract]
Distribution system improvement charge percentage over base rate			5.00%
Minimum [Member]
Rate Matters [Abstract]
Distribution system improvement charge percentage over base rate			0.00%