Other Investments - Servicing Advance Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Investment [Line Items]
Total Servicer Advance Receivables	$ 300,000
Residential Loans
Investment [Line Items]
Principal and interest advances	144,336	$ 0
Escrow advances (taxes and insurance advances)	94,828	0
Corporate advances	47,614	0
Total Servicer Advance Receivables	$ 286,778	$ 0

Line items represent reporting concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 12
-Sentence Column A

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Servicing Assets At Fair Value, Corporate Advances

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Servicing Assets At Fair Value, Escrow Advances

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Servicing Assets At Fair Value, Principal And Interest Advances

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122625-111746

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