SERVICING RIGHTS - Summary of Key Characteristics, Inputs and Economic Assumptions Used to Estimate Fair Value of MSRs (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Transfers and Servicing [Abstract]
Fair value of retained MSRs	$ 42,833	$ 76,121
Discount rate	10.95%	10.18%
Constant prepayment rate	12.83%	11.84%
Weighted-average life	6 years 2 months 13 days	6 years 6 months

Servicing Asset at Fair Value, Amount, Held-For-Investment and Disposal Group, Including Discontinued Operations, Servicing Asset at Fair Value, Amount, Held-For-Investment

No definition available.

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=64830801&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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=64830801&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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=64830801&loc=d3e107207-111719

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- References

No definition available.

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