SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - NEW ACCOUNTING PRONOUNCEMENTS RECENTLY ADOPTED (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Jan. 01, 2019
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating lease, right-of-use asset	$ 571
ASU 2016-02
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating lease, right-of-use asset		$ 736
Operating lease liability		$ 736