Mortgage Servicing Rights - Summary of Components of Net Carrying Value of Acquired and Originated MSRs (Detail) $ in Thousands	Mar. 31, 2016 USD ($)
Acquired MSRs
Mortgage Servicing Rights Acquired and Originated
Gross carrying value	$ 132,837
Accumulated amortization	(91,126)
Net carrying value	41,711
Originated MSRs
Mortgage Servicing Rights Acquired and Originated
Gross carrying value	538,924
Accumulated amortization	(158,984)
Net carrying value	379,940
MSRs
Mortgage Servicing Rights Acquired and Originated
Gross carrying value	671,761
Accumulated amortization	(250,110)
Net carrying value	$ 421,651

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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=26713463&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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