Investment Securities Available for Sale (Summary Of Sales Transactions In The Investment Securities Available For Sale Portfolio) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Investments [Abstract]
Proceeds from sales of investment securities available for sale	$ 968,606	$ 347,954	$ 20,815
Gross realized gains on sales (1)	9,586	4,356	1,419
Gross realized losses on sales	(3,575)	(1,587)	(88)
Investment securities gains, net	6,011	2,769	1,331
Available-for-sale securities, transfers, gains	1,400
Investment securities available for sale transferred to trading account assets at fair value	$ 1,890	$ 0	$ 0

Investment securities available for sale transferred to trading account assets at fair value

No definition available.

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- Definition

This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity 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)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563

+ Details

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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

+ Details

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- Definition

The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period.

+ References

+ Details

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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.

+ References

+ Details

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- Definition

This item represents the difference between the gross amount of gains (losses) included in earnings for transfers of securities from the available-for-sale category into the trading category. Such net gain (loss) included in earnings represents the net unrealized gain (loss) which had been included in other comprehensive income and is associated with the securities transferred from the available-for-sale category to the trading category.

+ 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 (d)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563

+ Details

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- References

No definition available.

+ Details

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