Regulatory Matters (Schedule of Compliance with Minimum Capital Requirements) (Details)	Dec. 31, 2017 Rate	Dec. 31, 2016 Rate
Regulatory Capital Requirements [Abstract]
Total capital to risk weighted assets (as a percent)	12.00%	11.90%
Tier 1 capital to risk weighted assets (as a percent)	9.90%	9.70%
Common Equity Tier 1 Capital to Risk Weighted Assets (as a percent)	9.40%	8.60%
Tier 1 Leverage Ratio (as a percent)	9.30%	8.90%

Total Capital divided by risk weighted assets as defined in the regulations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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Common Equity Tier One Risk Based Capital To Risk Weighted Assets

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