Derivative Financial Instruments - Effects of Derivative Instruments on Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Derivatives in Hedging Relationships [Member] \| Accumulated Other Comprehensive Loss and Other Interest Expense [Member]
Derivatives, Fair Value [Line Items]
Amount of gain (loss) reclassified from accumulated other comprehensive loss and recognized in other interest expense	$ 6	$ (99)
Derivatives not Designated as Hedging Instruments [Member] \| Mortgage Banking, Net [Member]
Derivatives, Fair Value [Line Items]
Amount of gain (loss) recognized in mortgage banking, net	(5,418)	(1,544)
Derivatives not Designated as Hedging Instruments [Member] \| Bank Card and Other Fees [Member]
Derivatives, Fair Value [Line Items]
Amount of gain (loss) recognized in bank card and other fees	$ 55	$ (28)

The amount of net gain (loss) recognized as noninterest income in bank card and other fees on derivative instruments not designated as hedging instruments.

No definition available.

+ Details

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- Definition

The amount of net gain (loss) recognized as noninterest income in mortgage banking, net on derivative instruments not designated as hedging instruments.

+ References

No definition available.

+ Details

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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

+ 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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- Details

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- Details

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- Details

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