MORTGAGE SERVICING RIGHTS - Summary of Components of Net Carrying Value of Acquired and Originated MSRs (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
MSRs
Mortgage Servicing Rights Acquired and Originated
Gross carrying value	$ 817,964	$ 644,752
Accumulated amortization	(296,034)	(232,404)
Net carrying value	521,930	412,348
Acquired MSRs
Mortgage Servicing Rights Acquired and Originated
Gross carrying value	175,934	132,837
Accumulated amortization	(104,264)	(84,754)
Net carrying value	71,670	48,083
Originated MSRs
Mortgage Servicing Rights Acquired and Originated
Gross carrying value	642,030	511,915
Accumulated amortization	(191,770)	(147,650)
Net carrying value	$ 450,260	$ 364,265

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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

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

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