MORTGAGE SERVICING RIGHTS - Summary of Components of Net Carrying Value of Acquired and Originated MSRs (Detail) $ in Thousands	Mar. 31, 2017 USD ($)
MSRs
Mortgage Servicing Rights Acquired and Originated
Gross carrying value	$ 880,174
Accumulated amortization	(317,644)
Net carrying value	562,530
Acquired MSRs
Mortgage Servicing Rights Acquired and Originated
Gross carrying value	175,934
Accumulated amortization	(109,552)
Net carrying value	66,382
Originated MSRs
Mortgage Servicing Rights Acquired and Originated
Gross carrying value	704,240
Accumulated amortization	(208,092)
Net carrying value	$ 496,148

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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.

+ References

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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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