COMMERCIAL MORTGAGE LOANS - Delinquent Loans (Details) - Commercial Mortgage Loans $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan
Delinquent loans
Commercial mortgage loans | $	$ 4,435	$ 7,165
Number of delinquent commercial mortgage loans | loan	3	5
30-59 Days Delinquent
Delinquent loans
Commercial mortgage loans | $	$ 2,175	$ 6,455
Number of delinquent commercial mortgage loans | loan	2	2
60-89 Days Delinquent
Delinquent loans
Commercial mortgage loans | $	$ 2,260	$ 0
Number of delinquent commercial mortgage loans | loan	1	0
Greater than 90 Days Delinquent
Delinquent loans
Commercial mortgage loans | $	$ 0	$ 710
Number of delinquent commercial mortgage loans | loan	0	3