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Effect of Derivative Instruments on Consolidated Statements of Income and Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended
	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

X

- 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

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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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