Reporting Segments and Related Information - Revenue Components of Real Estate Segments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Revenue from External Customer [Line Items]
Commercial/industrial revenues	$ 13,469	$ 5,702
Equity in earnings of unconsolidated joint ventures, net	167	228
Net operating income from commercial/industrial and unconsolidated joint ventures	1,981	(3,245)
Real estate - commercial/industrial
Revenue from External Customer [Line Items]
Commercial/industrial revenues	2,154	2,189
Equity in earnings of unconsolidated joint ventures, net	167	228
Total commercial/industrial revenues and equity in earnings from unconsolidated joint ventures	2,321	2,417
Net operating income from commercial/industrial and unconsolidated joint ventures	1,002	674
Real estate - commercial/industrial \| Pastoria Energy Facility
Revenue from External Customer [Line Items]
Commercial/industrial revenues	1,024	844
Real estate - commercial/industrial \| Tejon Ranch Commerce Center
Revenue from External Customer [Line Items]
Commercial/industrial revenues	407	527
Real estate - commercial/industrial \| TRCC management fees and reimbursements
Revenue from External Customer [Line Items]
Commercial/industrial revenues	213	212
Real estate - commercial/industrial \| Commercial leases
Revenue from External Customer [Line Items]
Commercial/industrial revenues	160	150
Real estate - commercial/industrial \| Communication leases
Revenue from External Customer [Line Items]
Commercial/industrial revenues	184	207
Real estate - commercial/industrial \| Landscaping and other
Revenue from External Customer [Line Items]
Commercial/industrial revenues	166	249
Real estate - commercial/industrial \| Land sale
Revenue from External Customer [Line Items]
Commercial/industrial revenues	$ 0	$ 0

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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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