Investment Securities (Narrative) (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Investment [Line Items]
Fair value of investments reported at less than historical cost	$ 67,500,000	$ 147,800,000
Percentage of Bank portfolio	25.90%	55.90%
Securities pledged as collateral	0	2,140,000
Proceeds from sales of securities, available for sale	28,317,000	53,179,000	98,326,000
Gross realized gain on sale of securities	1,176,000	898,000	2,831,000
Gross realized losses on sale of securities	$ 863,000	$ 63,000	$ 0
Banks, thrifts or other depository institutions to all projected defaults
Investment [Line Items]
Collateral recovery probability percentage	10.00%
Insurance Companies to all projected insurance defaults
Investment [Line Items]
Collateral recovery probability percentage	15.00%

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Percentage of expected recoveries to remaining performing collateral

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- Definition

Percentage Of Total Investment Portfolio In Unrealized Loss Position Fair Value

+ References

No definition available.

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(1)

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a)

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 5

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- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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-Publisher FASB

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-Topic 320

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-Section 45

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (a),(b)

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