Investment Securities (Summary Of Securities With Gross Unrealized Losses And Their Fair Values) (Details) $ in Thousands	Sep. 30, 2016 USD ($) security	Dec. 31, 2015 USD ($) security
Available-for-sale Securities and Held-to-maturity Securities
Number of Securities, Available for Sale \| security	67	124
Number of Securities, Held to Maturity \| security	4	1
Amortized cost of securities with unrealized losses, Available for Sale	$ 158,532	$ 253,872
Amortized cost of securities with unrealized losses, Held to Maturity	413	1,677
Continuous Unrealized Loss Existing for Less Than 12 Months, Available for Sale	(492)	(1,632)
Continuous Unrealized Loss Existing for Less Than 12 Months, Held to Maturity	(2)
Continuous Unrealized Loss Existing for More Than 12 Months, Available for Sale	(562)	(1,097)
Continuous Unrealized Loss Existing for More Than 12 Months, Held to Maturity		(3)
Fair value of securities with unrealized losses, Available for Sale	157,478	251,143
Fair value of securities with unrealized losses, Held to Maturity	$ 411	$ 1,674
Federal Agency Securities [Member]
Available-for-sale Securities and Held-to-maturity Securities
Number of Securities, Available for Sale \| security	7	14
Amortized cost of securities with unrealized losses, Available for Sale	$ 16,551	$ 42,438
Continuous Unrealized Loss Existing for Less Than 12 Months, Available for Sale	(112)	(138)
Continuous Unrealized Loss Existing for More Than 12 Months, Available for Sale	(43)	(235)
Fair value of securities with unrealized losses, Available for Sale	$ 16,396	$ 42,065
Obligations Of State And Political Subdivisions [Member]
Available-for-sale Securities and Held-to-maturity Securities
Number of Securities, Available for Sale \| security	3	14
Number of Securities, Held to Maturity \| security	4	1
Amortized cost of securities with unrealized losses, Available for Sale	$ 3,043	$ 11,765
Amortized cost of securities with unrealized losses, Held to Maturity	413	1,677
Continuous Unrealized Loss Existing for Less Than 12 Months, Available for Sale	(2)	(57)
Continuous Unrealized Loss Existing for Less Than 12 Months, Held to Maturity	(2)
Continuous Unrealized Loss Existing for More Than 12 Months, Available for Sale	(37)	(77)
Continuous Unrealized Loss Existing for More Than 12 Months, Held to Maturity		(3)
Fair value of securities with unrealized losses, Available for Sale	3,004	11,631
Fair value of securities with unrealized losses, Held to Maturity	$ 411	$ 1,674
Residential Mortgage-Backed Securities [Member]
Available-for-sale Securities and Held-to-maturity Securities
Number of Securities, Available for Sale \| security	52	87
Amortized cost of securities with unrealized losses, Available for Sale	$ 124,328	$ 175,043
Continuous Unrealized Loss Existing for Less Than 12 Months, Available for Sale	(378)	(1,247)
Continuous Unrealized Loss Existing for More Than 12 Months, Available for Sale	(236)	(605)
Fair value of securities with unrealized losses, Available for Sale	$ 123,714	$ 173,191
Asset-Backed Securities [Member]
Available-for-sale Securities and Held-to-maturity Securities
Number of Securities, Available for Sale \| security	3	3
Amortized cost of securities with unrealized losses, Available for Sale	$ 9,605	$ 9,639
Continuous Unrealized Loss Existing for Less Than 12 Months, Available for Sale		(115)
Continuous Unrealized Loss Existing for More Than 12 Months, Available for Sale	(181)	(109)
Fair value of securities with unrealized losses, Available for Sale	$ 9,424	$ 9,415
Corporate Debt [Member]
Available-for-sale Securities and Held-to-maturity Securities
Number of Securities, Available for Sale \| security	2	6
Amortized cost of securities with unrealized losses, Available for Sale	$ 5,005	$ 14,987
Continuous Unrealized Loss Existing for Less Than 12 Months, Available for Sale		(75)
Continuous Unrealized Loss Existing for More Than 12 Months, Available for Sale	(65)	(71)
Fair value of securities with unrealized losses, Available for Sale	$ 4,940	$ 14,841

Held to maturity securities continuous unrealized loss position amortized cost.

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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

+ 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)(2)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

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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.

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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity that have been in a continuous loss position for twelve months or longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity that have been in a continuous loss position for less than twelve months.

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Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired.

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