Fair Value Accounting (Changes In Level 3 Fair Value Measurements) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Investment Securities Available for Sale [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 1,638	$ 1,654	$ 1,745	$ 1,645
Included in earnings	0	0	0	0
Unrealized gains (losses) included in other comprehensive income	(13)	46	(120)	55
Purchases			0	0
Sales			0	0
Issuances			0	0
Settlements	0	0	0	0
Amortization of discount/premium			0	0
Transfers in and/or out of Level 3			0	0
Ending balance	1,625	1,700	1,625	1,700
Total net gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets still held at June 30,	0	0	0	0
Private Equity Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	26,757	27,081	27,148	27,367
Included in earnings	113	(122)	(278)	(408)
Unrealized gains (losses) included in other comprehensive income	0	0	0	0
Purchases			0	0
Sales			0	0
Issuances			0	0
Settlements	(4)	0	(4)	0
Amortization of discount/premium			0	0
Transfers in and/or out of Level 3			0	0
Ending balance	26,866	26,959	26,866	26,959
Total net gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets still held at June 30,	113	(122)	(278)	(408)
Visa Derivative [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	(1,415)	(1,425)	(1,415)	(1,401)
Included in earnings	(360)	(354)	(720)	(729)
Unrealized gains (losses) included in other comprehensive income	0	0	0	0
Purchases			0	0
Sales			0	0
Issuances			0	0
Settlements	360	364	720	715
Amortization of discount/premium			0	0
Transfers in and/or out of Level 3			0	0
Ending balance	(1,415)	(1,415)	(1,415)	(1,415)
Total net gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets still held at June 30,	$ (360)	$ (354)	$ (720)	$ (729)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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-Section 50
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- Definition

Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of increase (decrease) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of accretion (amortization) of purchase discount (premium) on nonoperating securities.

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