Fair Value Accounting (Changes In Fair Value Included In Consolidated Statements Of Income) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Mortgage loans held for sale	$ 754	$ (667)	$ (742)
Fair value	48,024	51,545	59,275
Unpaid principal balance	46,839	51,114	58,177
Fair value less aggregate unpaid principal balance	$ 1,185	$ 431	$ 1,098

Changes in the fair value of mortgage loans held for sale that were included in the consolidated statements of income during the reporting period.

No definition available.

+ Details

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Period Type:	duration

- Definition

Fair value option, aggregate unpaid principal balance of mortgage loans held for sale.

+ References

No definition available.

+ Details

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- Definition

The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624258-113959

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- References

No definition available.

+ Details

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- Definition

This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of long-term debt instruments that have contractual principal amounts and for which the fair value option has been elected.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612

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