INVESTMENTS - Net Realized Gain or Loss on Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Debt securities, gross realized gain	$ 0	$ 82
Equity securities and other investments, gross realized gain	0	2
Gross realized gains	0	84
Debt securities, gross realized loss	0	(16)
Equity securities and other investments, gross realized losses	0	(1,355)
Gross realized losses	0	(1,371)
Net realized gain (loss)	$ 0	$ (1,287)