Investment in Unconsolidated and Consolidated Joint Ventures - Condensed Statements of Operations and Balance Sheet Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Balance Sheet Information
Assets	$ 200,109	$ 175,691
Borrowings	(97,318)	(77,196)
Equity	99,265	94,454
Investment In	33,803	30,680
Statement of Operations
Revenues	128,564	128,192	$ 131,499
Earnings(Loss)	11,782	10,523	8,944
Equity in Earnings (Loss)	7,098	6,324	5,294
Petro Travel Plaza Holdings
Balance Sheet Information
Assets	68,652	64,484
Borrowings	(15,275)	(14,914)
Equity	51,287	46,710
Investment In	18,372	15,626
Statement of Operations
Revenues	114,947	115,776	122,584
Earnings(Loss)	12,077	10,629	8,229
Equity in Earnings (Loss)	7,246	6,377	4,937
Five West Parcel
Balance Sheet Information
Assets	16,614	17,278
Borrowings	(10,251)	(10,725)
Equity	6,043	6,213
Investment In	2,837	2,922
Statement of Operations
Revenues	2,887	3,408	3,635
Earnings(Loss)	1,029	1,084	442
Equity in Earnings (Loss)	515	542	221
18-19 West LLC
Balance Sheet Information
Assets	4,623	4,640
Borrowings	0	0
Equity	4,621	4,640
Investment In	1,741	1,750
Statement of Operations
Revenues	10	20	60
Earnings(Loss)	(129)	(108)	15
Equity in Earnings (Loss)	(65)	(54)	7
TRCC/Rock Outlet Center
Balance Sheet Information
Assets	86,056	89,289
Borrowings	(50,712)	(51,557)
Equity	34,523	36,891
Investment In	9,198	10,382
Statement of Operations
Revenues	9,542	8,988	5,220
Earnings(Loss)	(367)	(1,082)	328
Equity in Earnings (Loss)	(184)	(541)	164
TRCC/Rock Outlet Center | In-place leases, adjustment
Statement of Operations
Non-cash tenant allowance amortization	1,900	2,100	700
TRC-MRC 1 LLC
Balance Sheet Information
Assets	199	0
Borrowings	0	0
Equity	199	0
Investment In	224	0
Statement of Operations
Revenues	0	0	0
Earnings(Loss)	0	0	0
Equity in Earnings (Loss)	0	0	0
TRC-MRC 2 LLC
Balance Sheet Information
Assets	23,965	0
Borrowings	21,080	0
Equity	2,592	0
Investment In	1,431	0
Statement of Operations
Revenues	1,178	0	0
Earnings(Loss)	(828)	0	0
Equity in Earnings (Loss)	(414)	0	0
TRC-MRC 2 LLC | In-place leases, adjustment
Statement of Operations
Non-cash amortization of purchase accounting adjustments related to in-place leases	1,200
Tejon Mountain Village LLC
Statement of Operations
Revenues	0	0	0
Earnings(Loss)	0	0	(70)
Equity in Earnings (Loss)	0	0	(35)
Centennial-VIE
Balance Sheet Information
Assets	86,099	81,981
Borrowings	0	0
Equity	85,281	81,227
Statement of Operations
Revenues	520	749	1,361
Earnings(Loss)	$ (246)	$ (140)	$ 415