MORTGAGE LOANS - Impaired Loans (Details) - Commercial mortgage loans - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Recorded Investment
With no related allowance recorded	$ 83	$ 0
With an allowance recorded	8,331	5,684
Unpaid Principal Balance
With no related allowance recorded	83	0
With an allowance recorded	8,196	5,309
Related Allowance
With an allowance recorded	1,946	1,296
Average Recorded Investment
With no related allowance recorded	83	0
With an allowance recorded	4,165	1,895
Interest Income Recognized
With no related allowance recorded	0	0
With an allowance recorded	128	267
Cash Basis Interest Income
With no related allowance recorded	0	0
With an allowance recorded	$ 156	$ 293

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-Publisher FASB
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