Reporting Segments and Related Information - Revenue Components of Real Estate Segments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Revenue from External Customer [Line Items]
Commercial/industrial revenues	$ 5,702	$ 12,953
Equity in earnings of unconsolidated joint ventures, net	228	1,455
Net operating income from commercial/industrial and unconsolidated joint ventures	(3,245)	1,807
Real estate - commercial/industrial
Revenue from External Customer [Line Items]
Equity in earnings of unconsolidated joint ventures, net	228	1,455
Total commercial/industrial revenues and equity in earnings from unconsolidated joint ventures	2,417	3,609
Net operating income from commercial/industrial and unconsolidated joint ventures	674	1,930
Operating Segments \| Real estate - commercial/industrial
Revenue from External Customer [Line Items]
Commercial/industrial revenues	2,189	2,154
Operating Segments \| Real estate - commercial/industrial \| Pastoria Energy Facility Lease
Revenue from External Customer [Line Items]
Commercial/industrial revenues	844	871
Operating Segments \| Real estate - commercial/industrial \| Tejon Ranch Commerce Center
Revenue from External Customer [Line Items]
Commercial/industrial revenues	612	493
Operating Segments \| Real estate - commercial/industrial \| Commercial leases
Revenue from External Customer [Line Items]
Commercial/industrial revenues	302	401
Operating Segments \| Real estate - commercial/industrial \| Communication leases
Revenue from External Customer [Line Items]
Commercial/industrial revenues	207	196
Operating Segments \| Real estate - commercial/industrial \| Landscaping and other
Revenue from External Customer [Line Items]
Commercial/industrial revenues	$ 224	$ 193

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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