Fair Value Accounting (Changes In Level 3 Fair Value Measurements) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Investment Securities Available For Sale [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance, January 1,	$ 1,645	$ 2,350
Included in earnings	0	(88)
Unrealized gains (losses) included in other comprehensive income	100	(77)
Purchases	0	0
Sales	0	0
Issuances	0	0
Settlements	0	(540)
Amortization of discount/premium	0	0
Transfers in and/or out of Level 3	0	0
Ending balance, December 31,	1,745	1,645
Total net gains (losses) for the year included in earnings attributable to the change in unrealized gains (losses) relating to assets still held at December 31,	100	(88)
Private Equity Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance, January 1,	27,367	27,745
Included in earnings	(219)	(378)
Unrealized gains (losses) included in other comprehensive income	0	0
Purchases	0	0
Sales	0	0
Issuances	0	0
Settlements	0	0
Amortization of discount/premium	0	0
Transfers in and/or out of Level 3	0	0
Ending balance, December 31,	27,148	27,367
Total net gains (losses) for the year included in earnings attributable to the change in unrealized gains (losses) relating to assets still held at December 31,	(219)	(378)
Other Derivative Contracts, Net [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance, January 1,	(1,401)	(2,706)
Included in earnings	(1,464)	(3,041)
Unrealized gains (losses) included in other comprehensive income	0	0
Purchases	0	0
Sales	0	0
Issuances	0	0
Settlements	1,450	4,346
Amortization of discount/premium	0	0
Transfers in and/or out of Level 3	0	0
Ending balance, December 31,	(1,415)	(1,401)
Total net gains (losses) for the year included in earnings attributable to the change in unrealized gains (losses) relating to assets still held at December 31,	$ (1,464)	$ (3,041)

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

No definition available.

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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
-SubTopic 10
-Section 50
-Paragraph 2
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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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-Publisher FASB
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-Section 50
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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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