Reporting Segments and Related Information - Revenue Components of Real Estate Segments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenue from External Customer [Line Items]
Commercial/industrial revenues	$ 11,908	$ 13,079	$ 23,975	$ 32,881
Equity in earnings of unconsolidated joint ventures, net	1,724	2,353	3,512	5,650
Net operating income from commercial/industrial and unconsolidated joint ventures	310	588	(3,208)	1,287
Real estate - commercial/industrial
Revenue from External Customer [Line Items]
Commercial/industrial revenues	2,432	2,221	7,106	6,534
Equity in earnings of unconsolidated joint ventures, net	1,724	2,353	3,512	5,650
Total commercial/industrial revenues and equity in earnings from unconsolidated joint ventures	4,156	4,574	10,618	12,184
Net operating income from commercial/industrial and unconsolidated joint ventures	2,841	2,827	5,658	7,044
Real estate - commercial/industrial \| Pastoria Energy Facility Lease
Revenue from External Customer [Line Items]
Commercial/industrial revenues	1,054	967	2,779	2,698
Real estate - commercial/industrial \| Tejon Ranch Commerce Center
Revenue from External Customer [Line Items]
Commercial/industrial revenues	700	503	2,287	1,509
Real estate - commercial/industrial \| Commercial leases
Revenue from External Customer [Line Items]
Commercial/industrial revenues	309	378	901	1,182
Real estate - commercial/industrial \| Communication leases
Revenue from External Customer [Line Items]
Commercial/industrial revenues	229	205	603	595
Real estate - commercial/industrial \| Landscaping and other
Revenue from External Customer [Line Items]
Commercial/industrial revenues	140	168	536	550
Real estate - commercial/industrial \| Land Sale
Revenue from External Customer [Line Items]
Commercial/industrial revenues	$ 0	$ 0	$ 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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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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