NATURE OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Servicing Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounting Policies [Abstract]
Servicing Asset at Amortized Cost	$ 27,428	$ 25,255	$ 26,244	$ 24,282

Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 50
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Balance Type:	debit
Period Type:	instant