Long-Term Water Assets - Revenues and Cost of Sales (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2019 USD ($) acre ft	Jun. 30, 2018 USD ($) acre ft
Goodwill and Intangible Assets Disclosure [Abstract]
Acre-Feet Sold (in acre-feet) | acre ft	4,445	7,442
Revenues	$ 3,980	$ 7,992
Cost of sales	3,194	3,679
Profit	$ 786	$ 4,313