Reporting Segments and Related Information - Revenue Components of Real Estate Segments (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenue from External Customer [Line Items]
Commercial/industrial revenues	$ 6,365	$ 6,849	$ 12,067	$ 19,802
Equity in earnings of unconsolidated joint ventures, net	1,560	1,842	1,788	3,297
Net operating income from commercial/industrial and unconsolidated joint ventures	(273)	(1,108)	(3,518)	699
Real estate - commercial/industrial
Revenue from External Customer [Line Items]
Equity in earnings of unconsolidated joint ventures, net	1,560	1,842	1,788	3,297
Total commercial/industrial revenues and equity in earnings from unconsolidated joint ventures	4,045	4,001	6,462	7,610
Net operating income from commercial/industrial and unconsolidated joint ventures	2,143	2,287	2,817	4,217
Real estate - commercial/industrial \| Operating Segments
Revenue from External Customer [Line Items]
Commercial/industrial revenues	2,485	2,159	4,674	4,313
Real estate - commercial/industrial \| Operating Segments \| Pastoria Energy Facility Lease
Revenue from External Customer [Line Items]
Commercial/industrial revenues	881	860	1,725	1,731
Real estate - commercial/industrial \| Operating Segments \| Tejon Ranch Commerce Center
Revenue from External Customer [Line Items]
Commercial/industrial revenues	500	513	1,112	1,006
Real estate - commercial/industrial \| Operating Segments \| Commercial leases
Revenue from External Customer [Line Items]
Commercial/industrial revenues	290	399	592	800
Real estate - commercial/industrial \| Operating Segments \| Communication leases
Revenue from External Customer [Line Items]
Commercial/industrial revenues	167	198	374	394
Real estate - commercial/industrial \| Operating Segments \| Landscaping and other
Revenue from External Customer [Line Items]
Commercial/industrial revenues	172	189	396	382
Real estate - commercial/industrial \| Operating Segments \| Land Sale
Revenue from External Customer [Line Items]
Commercial/industrial revenues	$ 475	$ 0	$ 475	$ 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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