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Effect of Derivative Instruments on Consolidated Statements of Income and Comprehensive Income (Detail) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2016 | Mar. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gain Included in Mortgage Banking Income | $ 9,662 | $ 5,571
Treasury Options |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gain Included in Mortgage Banking Income | 7,231 | 3,416
Eurodollar Futures |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gain Included in Mortgage Banking Income | 66 | 383
Forward commitments to buy/sell loans/mortgage-backed securities |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gain Included in Mortgage Banking Income | 869 | $ 1,772
Swaps |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gain Included in Mortgage Banking Income | $ 1,496 |

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- Definition Amount of increase in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959 + Details
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- Definition 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 No definition available. + Details
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- Details
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