SERVICER ADVANCE INVESTMENTS - Schedule of Interest Income Related to Investments in Servicer Advances (Details) - Servicer Advance Investments - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Servicing Assets at Fair Value [Line Items]
Interest income, gross of amounts attributable to servicer compensation	$ 12,501	$ 34,262	$ 51,940
Amounts attributable to basic servicer compensation	(1,798)	(3,248)	(6,209)
Amounts attributable to incentive servicer compensation	(9,025)	(12,832)	(18,065)
Interest income from servicer advance investments	$ 1,678	$ 18,182	$ 27,666

Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.1-5)
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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Period Type:	duration