FAIR VALUE - General (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
FAIR VALUE
Fair value, assets, level 1 to level 2 transfers, amount	$ 0	$ 0
Fair value, assets, level 2 to level 1 transfers, amount	0	0
Fair value, liabilities, level 1 to level 2 transfers, amount	0	0
Fair value, liabilities, level 2 to level 1 transfers, amount	0	0
Transfer to level 3, assets, amount	0	0
Transfer from level 3, assets, amount	0	0
Transfer to level 3, liabilities, amount		0
Transfer from level 3, liabilities, amount	0	0
Fair value, equity, level 1 to level 2 transfers, amount	0	0
Fair value, equity, level 2 to level 1 transfers, amount	$ 0	$ 0