Investment Securities (Amortized Cost, Unrealized Gains And Losses, And Fair Value Of Investment Securities) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Investment Holdings [Line Items]
Available-for-sale Securities, Amortized Cost	$ 2,503,185	$ 2,278,932
Available-for-sale Securities, Unrealized Gains	39,885	31,524
Available-for-sale Securities, Unrealized Losses	(7,949)	(11,901)
Available for sale, at fair value	2,535,121us-gaap_AvailableForSaleSecurities	2,298,555us-gaap_AvailableForSaleSecurities
Held to maturity, at amortized cost	4,953us-gaap_HeldToMaturitySecurities	5,211us-gaap_HeldToMaturitySecurities
Held-to-maturity Securities, Unrealized Gains	478	358
Held-to-maturity Securities, Unrealized Losses	(2)	(15)
Held-to-maturity Securities, Fair Value	5,429	5,554
U.S. Treasury And Agencies [Member]
Investment Holdings [Line Items]
Available-for-sale Securities, Amortized Cost	213	213
Available-for-sale Securities, Unrealized Gains	16	16
Available-for-sale Securities, Unrealized Losses	0	0
Available for sale, at fair value	229	229
Obligations Of States And Political Subdivisions [Member]
Investment Holdings [Line Items]
Available-for-sale Securities, Amortized Cost	321,744	325,189
Available-for-sale Securities, Unrealized Gains	16,398	14,056
Available-for-sale Securities, Unrealized Losses	(540)	(841)
Available for sale, at fair value	337,602	338,404
Residential Mortgage-Backed Securities And Collateralized Mortgage Obligations [Member]
Investment Holdings [Line Items]
Available-for-sale Securities, Amortized Cost	2,179,212	1,951,514
Available-for-sale Securities, Unrealized Gains	23,398	17,398
Available-for-sale Securities, Unrealized Losses	(7,409)	(11,060)
Available for sale, at fair value	2,195,201	1,957,852
Held to maturity, at amortized cost	4,953	5,088
Held-to-maturity Securities, Unrealized Gains	478	358
Held-to-maturity Securities, Unrealized Losses	(2)	(15)
Held-to-maturity Securities, Fair Value	5,429	5,431
Investments In Mutual Funds And Other Equity Securities [Member]
Investment Holdings [Line Items]
Available-for-sale Securities, Amortized Cost	2,016	2,016
Available-for-sale Securities, Unrealized Gains	73	54
Available-for-sale Securities, Unrealized Losses	0	0
Available for sale, at fair value	2,089	2,070
Other Investments Securities [Member]
Investment Holdings [Line Items]
Held to maturity, at amortized cost		123
Held-to-maturity Securities, Unrealized Gains		0
Held-to-maturity Securities, Unrealized Losses		0
Held-to-maturity Securities, Fair Value		$ 123

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

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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-Publisher FASB

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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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.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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