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Effect of Derivative Instruments on Consolidated Statements of Income and Comprehensive Income (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
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Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
(Loss) Gain Included in Mortgage Banking Income | $ (6,211) | $ 3,913 | $ 6,056 | $ 2,990
Treasury Options |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
(Loss) Gain Included in Mortgage Banking Income | (6,245) | 2,485 | 3,619 | (2,589)
Eurodollar Futures |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
(Loss) Gain Included in Mortgage Banking Income | 17 | 1,134 | (38) | 1,495
Swaps |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
(Loss) Gain Included in Mortgage Banking Income | (1,751) |  | 2,427 |
Forward commitments to buy/sell loans/mortgage-backed securities |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
(Loss) Gain Included in Mortgage Banking Income | $ 1,768 | $ 294 | $ 48 | $ 4,084

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- Definition Amount of increase (decrease) 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 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959 Reference 2: 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=64837297&loc=SL5624171-113959 + 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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