Servicing of Residential Loans - Schedule of Fair Value Assumptions, Fair Value of Servicing Rights on Date of Sale (Detail)	1 Months Ended	11 Months Ended	12 Months Ended
Feb. 09, 2018	Dec. 31, 2018	Dec. 31, 2017
Transfers and Servicing [Abstract]
Weighted-average life in years	6 years 3 months	5 years 5 months	6 years 5 months
Weighted-average discount rate	14.75%	12.25%	14.27%
Weighted-average conditional prepayment rates	8.74%	11.94%	9.14%
Weighted-average conditional default rate	0.92%	1.11%	0.53%

Percentage of likelihood a loan will not be repaid and instead default on financial assets for initial fair value measurement.

No definition available.

+ Details

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- Definition

Discount rate which is used to value residual cash flows generated by financial assets of the securitization, asset-backed financing arrangement, or similar transfer for initial fair value measurement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=109247956&loc=d3e107207-111719

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- Definition

Estimated rate of prepayment of principal on financial assets for initial fair value measurement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=109247956&loc=d3e107207-111719

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- Definition

Weighted average life of securitized assets for initial fair value measurement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=109247956&loc=d3e107207-111719

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- References

No definition available.

+ Details

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