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Mortgage Servicing Rights - Details of Retention and Purchase of MSRs (Detail) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2016 | Mar. 31, 2015
Mortgage Servicing Rights [Line Items] |  |
MSRs recognized | $ 3,463 | $ 15,675
Mortgage servicing rights |  |
Mortgage Servicing Rights [Line Items] |  |
MSRs recognized | 8,807 | $ 18,754
Associated Principal | 870,071 |
Mortgage servicing rights | Jumbo Loan |  |
Mortgage Servicing Rights [Line Items] |  |
MSRs recognized | 46 |
Associated Principal | 6,519 |
Mortgage servicing rights | Jumbo Loan | Loan Sales |  |
Mortgage Servicing Rights [Line Items] |  |
MSRs recognized | 46 |
Associated Principal | 6,519 |
Mortgage servicing rights | Conforming Loan |  |
Mortgage Servicing Rights [Line Items] |  |
MSRs recognized | 8,761 |
Associated Principal | 863,552 |
Mortgage servicing rights | Conforming Loan | Loan Sales |  |
Mortgage Servicing Rights [Line Items] |  |
MSRs recognized | 3,364 |
Associated Principal | 314,518 |
Mortgage servicing rights | Conforming Loan | From purchases |  |
Mortgage Servicing Rights [Line Items] |  |
MSRs recognized | 5,397 |
Associated Principal | $ 549,034 |

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- Definition Mortgage Servicing Rights [Line Items] + References No definition available. + Details
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- Definition Amount of additions from purchases, assumption or transfer to 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)(2) -URI http://asc.fasb.org/extlink&oid=56950315&loc=d3e122739-111746 + Details
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- Definition The value of new servicing assets, subsequently measured at fair value, acquired or created during the current period through purchases or from transfers of financial assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 3 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=56950315&loc=d3e122625-111746 + Details
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