Long Term Water Assets - Additional Information (Details) $ in Thousands		12 Months Ended
	Aug. 06, 2015 $ / acre ft acre ft	Dec. 31, 2018 $ / acre ft	Dec. 31, 2017 USD ($) $ / acre ft acre ft	Dec. 31, 2016 USD ($) acre ft	Dec. 31, 2015 USD ($) acre ft	Dec. 31, 2013 acre ft	Dec. 31, 2009 acre ft	Dec. 31, 2008 acre ft
Long Lived Assets Held For Sale [Line Items]
Contract renewal optional term			35 years
Cost of purchased water | $			$ 765	$ 5,925	$ 5,483
Water sold (volume) (in acre-feet)			939	7,285	7,922
Water assets sales price | $			$ 1,254	$ 9,601	$ 10,165
Transferable water
Long Lived Assets Held For Sale [Line Items]
AVEK water bank (in acre-feet)			6,169
SWP contracts
Long Lived Assets Held For Sale [Line Items]
Water contract future amortization | $			$ 1,351
AVEK
Long Lived Assets Held For Sale [Line Items]
AVEK water bank (in acre-feet)			13,033	13,033			6,393	8,393
AVEK water for future delivery (in acre-feet)			0	2,362
AVEK | Transferable water
Long Lived Assets Held For Sale [Line Items]
AVEK water bank (in acre-feet)			1,452
SWP contracts
Long Lived Assets Held For Sale [Line Items]
AVEK water for future delivery (in acre-feet)							3,444
DMB Pacific LLC
Long Lived Assets Held For Sale [Line Items]
Contract renewal optional term			35 years
Consumer price per acre (per acre-foot) | $ / acre ft			717
DMB Pacific LLC | Maximum
Long Lived Assets Held For Sale [Line Items]
Annual fee increase, percent			3.00%
DMB Pacific LLC | Scenario, Forecast
Long Lived Assets Held For Sale [Line Items]
Consumer price per acre (per acre-foot) | $ / acre ft		738
DMB Pacific LLC | Transferable water
Long Lived Assets Held For Sale [Line Items]
Long-term water assets (Volume) (in acre-feet)			6,693			6,693
PEF | Transferable water | Ranchcorp
Long Lived Assets Held For Sale [Line Items]
Consumer price per acre (per acre-foot) | $ / acre ft	1,025
Annual fee increase, percent	3.00%
Annual option payment, percent	30.00%
PEF | Transferable water | Maximum | Ranchcorp
Long Lived Assets Held For Sale [Line Items]
Water assets, volume available for purchase in 2016 (up to) (in acre-feet)	2,000
Water assets, volume available for purchase from 2017-2030 (up to) (in acre-feet)	3,500