Income Taxes Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Line Items]
Gains (Losses) on Sales of Investment Real Estate	$ 50,000	$ 4,582,000	$ 1,126,000
Income Tax Expense (Benefit)	124,000	854,000	(583,000)
Current Income Tax Expense (Benefit)		42,000
Deferred Tax Assets, Gross	334,000	433,000
Income (Loss) from Subsidiaries, Tax Expense (Benefit)	0	749,000	(707,000)
Income Taxes Paid	170,000	30,000	122,000
Texas Franchise Tax [Member]
Income Taxes [Line Items]
Income Tax Expense (Benefit)	124,000	105,000	124,000
Grangeville, ID [Member]
Income Taxes [Line Items]
Gains (Losses) on Sales of Investment Real Estate	$ 1,654,000
Taxable REIT Subsidiary [Member]
Income Taxes [Line Items]
Income Tax Expense (Benefit)		$ 749,000	$ (707,000)