Mortgage Servicing Rights - Schedule of Activity Related to Capitalized MSRs (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
MSRs
Beginning balance	$ 375,907
Ending balance	412,348	$ 375,907
MSRs
MSRs
Beginning balance	375,907	353,024
Additions, following sale of loan	135,441	96,949
Additions, acquisitions		8,209
Amortization	(80,702)	(69,099)
Pre-payments and write-offs	(18,298)	(13,176)
Ending balance	$ 412,348	$ 375,907

Amount of other-than-temporary impairment (OTTI) applied to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (a)(6)
-URI http://asc.fasb.org/extlink&oid=56950315&loc=d3e122739-111746

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- Definition

Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=7524895&loc=d3e120260-111741

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122492-111745

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=56950315&loc=d3e122739-111746

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Amount of amortization of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=56950315&loc=d3e122739-111746

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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.

+ References

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Amount of additions from transfer to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

No definition available.

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The value of new servicing assets, subsequently measured at amortized cost, acquired through a business combination.

+ References

No definition available.

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