Long-Term Water Assets - Value of Water Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Components of water assets
Total long-term assets	$ 45,495	$ 46,700
less: Current portion	(1,351)	(1,351)
Long-term water assets	44,144	45,349
Banked water and water for future delivery
Components of water assets
Total long-term assets	4,779	4,779
Transferable water
Components of water assets
Total long-term assets	9,117	9,309
SWP contracts
Components of water assets
Total long-term assets	31,599	32,612
Accumulated amortization	$ 5,201	$ 4,188