Quarterly report pursuant to Section 13 or 15(d)

INVESTMENTS HELD-TO-MATURITY (Details)

v3.19.2
INVESTMENTS HELD-TO-MATURITY (Details) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Dec. 31, 2018
Schedule of Held-to-maturity Securities [Line Items]          
Amortized cost $ 4,500,000   $ 4,500,000    
Fair value 4,500,000   4,500,000    
Unrealized gain (loss)     0    
Investments held-to-maturity 4,483,000   4,483,000   $ 16,863,000
Interest and investment income 72,000 $ 98,000 178,000 $ 146,000  
Commercial Paper | Commercial Paper, Maturing August 2019          
Schedule of Held-to-maturity Securities [Line Items]          
Investments held-to-maturity 3,000,000   3,000,000    
Commercial Paper | Commercial Paper, Maturing September 2019          
Schedule of Held-to-maturity Securities [Line Items]          
Investments held-to-maturity $ 1,500,000   $ 1,500,000