Investment Securities (Schedule Of Investment Securities) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Schedule of Investments [Line Items]
Securities Available-for-Sale, Amortized Cost	$ 990,116	$ 1,099,658
Securities Available-for-Sale, Gross Unrealized Holdings Gains	14,450	16,523
Securities Available-for-Sale, Gross Unrealized Holding Losses	3,315	1,727
Securities Available-for-Sale, Estimated Fair Value	1,001,251	1,114,454
Securities Held-to-Maturity, Amortized Cost	285,250	401,390
Securities Held-to-Maturity, Gross Unrecognized Holding Gains	9,064	9,353
Securities Held-to-Maturity, Gross Unrecognized Holding Losses		38
Securities Held-to-Maturity, Estimated Fair Value	294,314	410,705
Obligations Of U.S. Treasury And Other U.S. Government Sponsored Entities [Member]
Schedule of Investments [Line Items]
Securities Available-for-Sale, Amortized Cost	570,639	695,655
Securities Available-for-Sale, Gross Unrealized Holdings Gains	338	1,352
Securities Available-for-Sale, Gross Unrealized Holding Losses	2,957	1,280
Securities Available-for-Sale, Estimated Fair Value	568,020	695,727
Obligations Of States And Political Subdivisions [Member]
Schedule of Investments [Line Items]
Securities Available-for-Sale, Amortized Cost	984	984
Securities Available-for-Sale, Gross Unrealized Holdings Gains	11	19
Securities Available-for-Sale, Gross Unrealized Holding Losses
Securities Available-for-Sale, Estimated Fair Value	995	1,003
Securities Held-to-Maturity, Amortized Cost	485	570
Securities Held-to-Maturity, Gross Unrecognized Holding Gains	1	2
Securities Held-to-Maturity, Gross Unrecognized Holding Losses
Securities Held-to-Maturity, Estimated Fair Value	486	572
U.S. Government Sponsored Entities Asset-Backed Securities [Member]
Schedule of Investments [Line Items]
Securities Available-for-Sale, Amortized Cost	417,356	401,882
Securities Available-for-Sale, Gross Unrealized Holdings Gains	12,869	14,067
Securities Available-for-Sale, Gross Unrealized Holding Losses	358	447
Securities Available-for-Sale, Estimated Fair Value	429,867	415,502
Securities Held-to-Maturity, Amortized Cost	284,765	400,820
Securities Held-to-Maturity, Gross Unrecognized Holding Gains	9,063	9,351
Securities Held-to-Maturity, Gross Unrecognized Holding Losses		38
Securities Held-to-Maturity, Estimated Fair Value	293,828	410,133
Other Equity Securities [Member]
Schedule of Investments [Line Items]
Securities Available-for-Sale, Amortized Cost	1,137	1,137
Securities Available-for-Sale, Gross Unrealized Holdings Gains	1,232	1,085
Securities Available-for-Sale, Gross Unrealized Holding Losses
Securities Available-for-Sale, Estimated Fair Value	$ 2,369	$ 2,222

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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+ Details

- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References+ Details

- Definition

This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

+ References+ Details

- Definition

For an unclassified balance sheet, this item represents investments in debt securities which are categorized as held-to-maturity. The held-to-maturity category is for those securities that the entity has the positive intent and ability to hold until maturity.

+ References

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+ Details

- Definition

This item represents the aggregate fair value of investments in debt securities as of the balance sheet date and which are categorized as held-to-maturity.

+ References+ Details

- Definition

As of the balance sheet date, the excess of fair value over carrying value (amortized cost) of a debt security categorized as held-to-maturity, exclusive of dividend or interest income recognized but not yet received and exclusive of any write-downs for other-than-temporary impairment. Such item represents the gross unrecognized holding gain.

+ References+ Details

- Definition

As of the balance sheet date, the excess of carrying value (amortized cost) over fair value of a debt security categorized as held-to-maturity, exclusive of dividend or interest income recognized but not yet received and exclusive of any write-downs for other-than-temporary impairment. Such item represents the gross unrecognized holding loss.

+ References+ Details