Discontinued Operations and Assets and Liabilities Held-for-Sale - Results from Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cost of sales and expenses from discontinued real estate operations:
Net income (loss) from discontinued operations, net of tax		$ 3,887
Gain (loss) on sale of discontinued operation		(7,146)
Net loss from discontinued operations, net of tax	$ 0	(3,259)
Net (income) loss from discontinued operations attributable to noncontrolling interests		(1,391)
Net income (loss) from discontinued operations attributable to PICO Holdings, Inc.		(4,650)
Real Estate Operations
Revenue and other income from discontinued real estate operations:
Sales of real estate		94,498
Other		448
Total revenue and other income		94,946
Cost of sales and expenses from discontinued real estate operations:
Cost of real estate sold		77,128
General, administrative, and other		8,215
Sales and marketing		5,149
Impairment loss on long-lived assets		102
Total cost of sales and expenses		90,594
Income (loss) before income taxes		4,352
Benefit (provision) for federal and state income taxes		(521)
Net income (loss) from discontinued operations, net of tax		3,831
Gain (loss) on sale of discontinued operation		(7,148)
Agribusiness Operations
Cost of sales and expenses from discontinued real estate operations:
Net income (loss) from discontinued operations, net of tax		56
Gain (loss) on sale of discontinued operation		$ 2