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Mortgage Servicing Rights - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Mortgage Loan Activity [Line Items] |  |  |
Sale of 1-4 family mortgage loans to Federal National Mortgage Association (FNMA) | $ 99,458 | $ 42,361 | $ 87,932
Total servicing portfolio | 361,200 | 325,800 | 327,400
Federal National Mortgage Association or (FNMA) |  |  |
Mortgage Loan Activity [Line Items] |  |  |
Sale of 1-4 family mortgage loans to Federal National Mortgage Association (FNMA) | $ 76,800 | $ 40,100 | $ 62,900

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- Definition The cash inflow from sales of loans that are secured with real estate mortgages and are held with the intention to resell in the near future. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 21 -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3461-108585 + Details
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