FAIR VALUE MEASUREMENTS (Details) - Recurring [Member] - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Institutional Money Market [Member]
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	$ 950,658	$ 6,078,025
Certificates of Deposit [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	7,287,409	5,090,631
Municipal Bonds [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	11,341,249	1,295,350
Government Agency Bonds [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	18,182,542
Corporate Bonds [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	63,997,742	62,420,996
Level 1 [Member] | Institutional Money Market [Member]
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	950,658	6,078,025
Level 1 [Member] | Certificates of Deposit [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	7,287,409	5,090,631
Level 1 [Member] | Municipal Bonds [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	0	0
Level 1 [Member] | Government Agency Bonds [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	0
Level 1 [Member] | Corporate Bonds [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	0	0
Level 2 [Member] | Institutional Money Market [Member]
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	0	0
Level 2 [Member] | Certificates of Deposit [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	0	0
Level 2 [Member] | Municipal Bonds [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	11,341,249	1,295,350
Level 2 [Member] | Government Agency Bonds [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	18,182,542
Level 2 [Member] | Corporate Bonds [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	63,997,742	62,420,996
Level 3 [Member] | Institutional Money Market [Member]
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	0	0
Level 3 [Member] | Certificates of Deposit [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	0	0
Level 3 [Member] | Municipal Bonds [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	0	0
Level 3 [Member] | Government Agency Bonds [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	0
Level 3 [Member] | Corporate Bonds [Member]
Assets, Fair Value Disclosure [Abstract]
Investments	$ 0	$ 0