Consolidated Balance Sheets (Parenthetical) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Available-for-sale Securities Pledged as Collateral (in dollars)		$ 1,295,225,428
Loan discount	$ 2,440,674
Deferred financing costs	$ 3,761,410
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	50,000,000	50,000,000
Preferred stock, dividend rate (percentage)	8.75%	8.75%
Preferred stock, liquidation preference, value (in dollars)	$ 25	$ 25
Preferred stock, shares issued (in shares)	1,610,000	1,610,000
Preferred stock, shares outstanding (in shares)	1,610,000	1,610,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	450,000,000	450,000,000
Common stock, shares issued (in shares)	23,687,664	22,143,758
Common stock, shares outstanding (in shares)	23,687,664	22,143,758

Face amount or stated value per share of common stock.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The fair value, as of the date of each statement of financial position presented, of other securities, classified as available for sale or held for investment, which are owned but transferred to serve as collateral for the payment of the related debt obligation, primarily a secured borrowing or repurchase agreement, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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