Consolidated Statements of Comprehensive Income (Loss) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (5,471,462)	$ 4,706,961
Other comprehensive income (loss):
Increase (decrease) in net unrealized gain (loss) on available-for-sale securities, net	0	(13,268,331)
Reclassification adjustment for net loss included in net income	12,617,794	7,482,477
Total other comprehensive income (loss)	12,617,794	(5,785,854)
Less: Dividends to preferred stockholders	(3,528,588)	(3,522,036)
Comprehensive income (loss) attributable to common stockholders	$ 3,617,744	$ (4,600,929)