NON-CONSOLIDATED VARIABLE INTEREST ENTITIES AND SERVICING ASSETS - Changes in Impairment Allowance (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Transfers and Servicing [Abstract]
Balance at beginning of period	$ 1,451	$ 461	$ 136
Temporary impairment charges	123	1,611	466
OTTI of servicing assets	(132)	(621)	0
Recoveries	(1,412)	0	(141)
Balance at end of period	$ 30	$ 1,451	$ 461

No definition available.

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- Definition

Amount of decrease in the valuation allowance for impairment of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer from write-downs charged against the allowance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (e)(3)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

+ Details

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- Definition

Reflects the estimated amount of impairment as of the balance sheet date of recognized servicing assets that are being amortized in proportion to and over the period of estimated net servicing income or loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

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- Definition

Amount of increase in the valuation allowance for impairment of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer from charges to expense.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (e)(2)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

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- Definition

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (e)(2)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

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