Reporting Segments and Related Information - Information Pertaining to Assets of Segments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Information pretaining to assets of the business segments
Identifiable Assets	$ 539,422	$ 529,048	$ 518,199
Depreciation and Amortization	5,036	5,424	5,689
Capital Expenditures	25,222	22,580	21,709
Operating Segments | Real estate - commercial/industrial
Information pretaining to assets of the business segments
Identifiable Assets	76,814	65,929	63,065
Depreciation and Amortization	517	651	650
Capital Expenditures	8,690	5,225	4,638
Operating Segments | Real estate - resort/residential
Information pretaining to assets of the business segments
Identifiable Assets	286,801	273,620	258,697
Depreciation and Amortization	51	58	63
Capital Expenditures	12,811	13,459	14,230
Operating Segments | Mineral resources
Information pretaining to assets of the business segments
Identifiable Assets	55,049	54,144	48,305
Depreciation and Amortization	1,371	1,372	1,363
Capital Expenditures	37	171	356
Operating Segments | Farming
Information pretaining to assets of the business segments
Identifiable Assets	41,258	40,835	36,317
Depreciation and Amortization	1,909	1,897	2,080
Capital Expenditures	3,362	3,166	2,129
Operating Segments | Ranch operations
Information pretaining to assets of the business segments
Identifiable Assets	2,624	2,973	3,625
Depreciation and Amortization	526	536	601
Capital Expenditures	213	102	220
Corporate
Information pretaining to assets of the business segments
Identifiable Assets	76,876	91,547	108,190
Depreciation and Amortization	662	910	932
Capital Expenditures	$ 109	$ 457	$ 136