Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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=84234895&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
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-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ 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 (c)
-URI http://asc.fasb.org/extlink&oid=84234895&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 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959

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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.

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No definition available.

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Derivatives - Schedule of Gains (Losses) Included in the Consolidated Statements of Income Related to Derivative Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Derivatives Fair Value [Line Items]
Gains (losses) on derivative financial instruments	$ (1,456)	$ (5,361)	$ 4,869	$ (5,739)
Derivatives Not Designated As Hedging Instruments \| Included in Mortgage Banking Income \| Interest rate-lock commitments
Derivatives Fair Value [Line Items]
Gains (losses) on derivative financial instruments	(684)	(1,433)	2,727	1,509
Derivatives Not Designated As Hedging Instruments \| Included in Mortgage Banking Income \| Forward commitments
Derivatives Fair Value [Line Items]
Gains (losses) on derivative financial instruments	635	$ (3,928)	5,953	$ (7,248)
Derivatives Not Designated As Hedging Instruments \| Included in Mortgage Banking Income \| Futures Contracts
Derivatives Fair Value [Line Items]
Gains (losses) on derivative financial instruments	(1,369)		(3,816)
Derivatives Not Designated As Hedging Instruments \| Included in Mortgage Banking Income \| Option Contracts
Derivatives Fair Value [Line Items]
Gains (losses) on derivative financial instruments	(38)		5
Designated as Hedging
Derivatives Fair Value [Line Items]
Amount of gain (loss) reclassified from other comprehensive income and recognized in interest expense on long-term debt	$ 25		$ (7)