INVESTMENTS IN EXCESS MORTGAGE SERVICING RIGHTS - Narrative (Details)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
MSRs \| Excess MSRs Investees
Investment [Line Items]
Weighted average discount rate, used to value investments in excess MSRs	8.80%	8.90%

The average discount rate applied to insurance contracts to determine future policy benefits to be paid to or on behalf of policyholders.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=99384497&loc=d3e14881-158438

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