Federal Income Taxes (Details Narrative) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Preferred Dividends Paid, net	$ 16,665,934	$ 14,563,645	$ 7,556,588
Preferred stock, dividend declared per share, paid	$ (0.52)	$ (0.51)	$ (0.32)
S&F Tax [Member]
Amount of operating losses of S&F	$ 2,066,587	$ 2,307,104	$ 3,550,961
Federal state and franchise taxes included in general and administrative expenses	0	5,000	15,000
Series A Preferred Stock [Member]
Preferred Dividends Paid, net	$ 5,667,441	$ 7,556,588	$ 7,556,588
Preferred stock, dividend declared per share, paid	$ 1.546875	$ 2.0625	$ 2.0625
Percentage of distributions characterized as ordinary income	0.494148	1.79472	1.36264
Percentage of distributions characterized as capital gains	0.138204	$ 0.26778	0.03439
Percentage of distributions characterized as return capital	$ 0.914523		$ 0.66547
Series B Preferred Stock [Member]
Preferred Dividends Paid, net	$ 7,602,400	$ 7,007,057
Preferred stock, dividend declared per share, paid	$ 2.00	$ 2.22466
Percentage of distributions characterized as ordinary income	0.638896	1.93582
Percentage of distributions characterized as capital gains	0.178688	$ 0.28884
Percentage of distributions characterized as return capital	$ 1.182416
Series C Preferred Stock [Member]
Preferred Dividends Paid, net	$ 3,396,094
Preferred stock, dividend declared per share, paid	$ 0.590625
Percentage of distributions characterized as ordinary income	0.188674
Percentage of distributions characterized as capital gains	0.052769
Percentage of distributions characterized as return capital	$ 0.349182