INVESTMENT SECURITIES (Tables)

3 Months Ended

Mar. 31, 2016

Investments, Debt and Equity Securities [Abstract]

Held-to-maturity Securities [Table Text Block]

The following tables summarize our investment securities at March 31, 2016 and December 31, 2015:

	March 31, 2016
			Gross		Gross
	Amortized cost,		unrealized		unrealized		Estimated fair
	as adjusted		holding gains		holding losses		value
Short-term investments:
Obligations of domestic governmental agencies (maturing between April 2016 and March 2017) (held-to-maturity)	$	22,224,258	$	3,012	$	2,191	$	22,225,079
Long-term investments:
Obligations of domestic governmental agencies (maturing between April 2017 and January 2018) (held-to-maturity)		26,458,226		48,451		4,828		26,501,849
Total short-term and long-term investment securities	$	48,682,484	$	51,463	$	7,019	$	48,726,928

	December 31, 2015
			Gross		Gross
	Amortized cost,		unrealized		unrealized		Estimated fair
	as adjusted		holding gains		holding losses		value
Short-term investments:
Obligations of domestic governmental agencies (maturing between January 2016 and December 2016) (held-to-maturity)	$	22,166,512	$	—	$	22,822	$	22,143,690
Long-term investments:
Obligations of domestic governmental agencies (maturing between January 2017 and December 2017) (held-to-maturity)		25,003,032		—		85,846		24,917,186
Total short-term and long-term investment securities	$	47,169,544	$	—	$	108,668	$	47,060,876