Residential Mortgage Servicing Rights (Sensitivity Analysis of Current Fair Value to Changes in Discount and Prepayment Speed Assumptions) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Transfers and Servicing [Abstract]
Effect on fair value of a 10% adverse change	$ (7,036)	$ (6,290)
Effect on fair value of a 20% adverse change	(13,527)	(12,093)
Effect on fair value of a 100 basis point adverse change	(6,836)	(5,840)
Effect on fair value of a 200 basis point adverse change	$ (13,156)	$ (11,249)

Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of One Percent Adverse Change in Discount Rate

No definition available.

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- Definition

Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of Two Percent Adverse Change in Discount Rate

+ References

No definition available.

+ Details

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- Definition

The hypothetical financial impact of a 10 percent adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109247956&loc=d3e107314-111719

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- Definition

The hypothetical financial impact of a 20 percent adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

+ Details

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- References

No definition available.

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