BUSINESS ACQUISITIONS - Schedule of Unaudited Supplemental Pro Forma Financial Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Ditech Acquisition
Pro Forma (in millions)
Servicing and Origination Revenue	$ 1,104.0	$ 1,238.1
Income Before Income Taxes	552.8	923.3
Guardian
Pro Forma (in millions)
Income Before Income Taxes	$ 651.5	932.2
Shellpoint Acquisition
Pro Forma (in millions)
Servicing and Origination Revenue		767.0	$ 749.0
Income Before Income Taxes		$ 948.1	$ 1,197.5

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration