Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with interest rate reset through auction process, sold at par value.

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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AVAILABLE-FOR-SALE SECURITIES - Realized Gain (Loss) from Sale of AFS Securities (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Available for sale securities		$ 0	$ 0
AFS Securities
Debt Securities, Available-for-sale [Line Items]
AFS securities sold, at cost	$ 147,058,544
Proceeds from AFS securities sold	144,210,537
Net realized gain (loss) on sale of AFS securities	$ (2,848,007)