Mortgage Servicing Rights - Summary of Components of Net Carrying Value of Acquired and Originated MSRs (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Acquired MSRs
Mortgage Servicing Rights Acquired and Originated
Gross carrying value	$ 132,837	$ 132,837
Accumulated amortization	(84,754)	(59,128)
Net carrying value	48,083	73,709
Originated MSRs
Mortgage Servicing Rights Acquired and Originated
Gross carrying value	511,915	427,941
Accumulated amortization	(147,650)	(125,743)
Net carrying value	364,265	302,198
MSRs
Mortgage Servicing Rights Acquired and Originated
Gross carrying value	644,752	560,778
Accumulated amortization	(232,404)	(184,871)
Net carrying value	$ 412,348	$ 375,907

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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.

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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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