Investment Securities (Proceeds From Sales Of Securities And Components Of Investment Securities Gains And Losses) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Investment [Line Items]
Proceeds from sales of available for sale securities	$ 30,998	$ 7,076	$ 5,231
Proceeds from sales of non-marketable securities	33,444	9,223	11,644
Total proceeds	64,442	16,299	16,875
Investment securities gains (losses), net	14,124us-gaap_GainLossOnInvestments	(4,425)us-gaap_GainLossOnInvestments	4,828us-gaap_GainLossOnInvestments
Available-for-sale Securities [Member]
Investment [Line Items]
Gains realized on sales	0	126	358
Loss realized on sales	5,197	0	0
Gain realized on donation	1,570	1,375	0
Other-than-temporary impairment recognized on debt securities	1,365	1,284	1,490
Non-Marketable [Member]
Investment [Line Items]
Gains realized on sales	1,629	1,808	1,655
Losses realized on sales	(134)	(2,979)	(200)
Fair value adjustments, net	$ 17,621	$ (3,471)	$ 4,505

Fair value adjustments on non-marketable securities.

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- Definition

Gain realized on donation

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- Definition

Nonmarketable Securities Gain On Sale

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- Definition

Nonmarketable Securities Loss On Sale

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- Definition

Proceeds from non-marketable and available for sale securities

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- Definition

Proceeds From Sale Of Nonmarketable Securities

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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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- Definition

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

This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

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-Topic 225

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-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(c),9(a))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

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- Definition

Amount before tax of reclassification adjustment for other than temporary impairment (OTTI) related to factors other than credit loss on a previously impaired investment in available-for-sale debt security.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 9A

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- Definition

The cash inflow associated with the sale or maturity (principal being due) of securities not classified as either held-to-maturity securities or trading securities which are classified as available-for-sale securities.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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-Paragraph 12

-Subparagraph (a),(b)

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