MORTGAGE SERVICING RIGHTS - Summary of Components of Net Carrying Value of Acquired and Originated MSRs (Detail) - MSRs - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Mortgage Servicing Rights Acquired and Originated
Gross value	$ 1,168,058	$ 1,100,439
Accumulated amortization	(470,708)	(430,293)
Net carrying value	$ 697,350	$ 670,146

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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