Mortgage Servicing Rights - Summary of Net Mortgage Loan Servicing Fees Relating to MSRs (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Transfers And Servicing [Abstract]
Contractually-specified servicing fees	$ 125,961	$ 97,633	$ 76,300
Late charges	570	328	0
Other	5,302	4,186	3,708
Net mortgage loan servicing fees	$ 131,833	$ 102,147	$ 80,008

All amounts that are due to the servicer of a financial asset, excluding contractually specified servicing fees and late fees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122596-111746

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- Definition

All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

+ References

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- Definition

The total amount of contractually specified servicing fees, late fees, and ancillary fees earned for each period for which results of operations are presented.

+ References

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- Definition

All amounts that are due to the servicer of a financial asset as a result of the debt holder not meeting the monthly payment terms.

+ References

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- References

No definition available.

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