Investment Securities (Summary Of Investment Securities) (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Investment [Line Items]
Held-to-maturity, fair value	$ 635,379	$ 609,547
Held-to-maturity, Amortized cost	647,386	630,574
Held To Maturity Securities Gross Unrealized Gains	0
Held To Maturity Securities Gross Unrealized Gains Losses 1		0
Held To Maturity Securities Gross Unrealized Losses	41,107
Held To Maturity Securities Gross Unrealized Losses 1		41,593
Held-to-maturity, Carrying value	606,279	588,981
Available-for-sale debt securities, Amortized cost	3,323,647
Available-For-Sale Debt Securities, Gross Unrealized Gains, Recognized In O C I	48,464
Available-For-Sale Debt Securities, Gross Unrealized Losses, Recognized In O C I	200,968
Available-For-Sale Securities, Debt Securities, Net Carrying Amount	3,171,143
Available-for-sale debt securities, Estimated fair value	3,171,143	3,421,683
Available-for-sale Securities, Gross Unrealized Gain	48,644	48,345
Available-for-sale equity securities, Amortized cost		3,661,627
Gross Unrealized Gains on Debt Securities		48,324
Gross Unrealized Losses on AFS Debt Securities		288,268
Available-for-sale equity securities, Carrying value		3,421,683
Available-for-sale, Amortized cost	3,581,290	3,949,230
Available-for-sale, Gross unrealized losses, Recognized in OCI	206,729	295,689
Carrying value	3,423,205	3,701,886
Available-for-sale securities, Estimated fair value	3,423,205	3,701,886
Held-to-maturity Securities, Unrecognized Holding Gain	32,032	26,490
Held-to-maturity Securities, Unrecognized Holding Loss	2,932	5,924
amortized cost of investment securities	4,228,676	4,579,804
Gross Unrealized Gains of Investment Securities Recognized in OCI	48,644	48,345
Gross Unrealized Losses of Investment Securities Recognized in OCI	247,836	337,282
Carrying Value of Investment Securities	4,029,484	4,290,867
Estimated Fair Value of Investment Securities	4,058,584	4,311,433
Municipal Securities [Member]
Investment [Line Items]
Held-to-maturity, fair value	580,657	557,734
Held-to-maturity, Amortized cost	567,935	551,055
Held To Maturity Securities Gross Unrealized Gains	0
Held To Maturity Securities Gross Unrealized Gains Losses 1		0
Held To Maturity Securities Gross Unrealized Losses	0
Held To Maturity Securities Gross Unrealized Losses 1		0
Held-to-maturity, Carrying value	567,935	551,055
Available-for-sale debt securities, Amortized cost	150,897	65,425
Available-For-Sale Debt Securities, Gross Unrealized Gains, Recognized In O C I	1,213
Available-For-Sale Debt Securities, Gross Unrealized Losses, Recognized In O C I	704
Available-For-Sale Securities, Debt Securities, Net Carrying Amount	151,406	66,264
Available-for-sale debt securities, Estimated fair value	151,406	66,264
Available-for-sale Securities, Gross Unrealized Gain		1,329
Available-for-sale, Gross unrealized losses, Recognized in OCI		490
Held-to-maturity Securities, Unrecognized Holding Gain	14,429	11,295
Held-to-maturity Securities, Unrecognized Holding Loss	1,707	4,616
Trust Preferred Securities - Banks And Insurance [Member] | Asset-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity, fair value	54,622	51,713
Held-to-maturity, Amortized cost	79,351	79,419
Held To Maturity Securities Gross Unrealized Gains	0
Held To Maturity Securities Gross Unrealized Gains Losses 1		0
Held To Maturity Securities Gross Unrealized Losses	41,107
Held To Maturity Securities Gross Unrealized Losses 1		41,593
Held-to-maturity, Carrying value	38,244	37,826
Available-for-sale debt securities, Amortized cost	934,353
Available-For-Sale Debt Securities, Gross Unrealized Gains, Recognized In O C I	13,578
Available-For-Sale Debt Securities, Gross Unrealized Losses, Recognized In O C I	188,520
Available-For-Sale Securities, Debt Securities, Net Carrying Amount	759,411
Available-for-sale debt securities, Estimated fair value	759,411
Available-for-sale Securities, Gross Unrealized Gain		13,439
Available-for-sale equity securities, Amortized cost		1,508,224
Available-for-sale equity securities, Carrying value		1,238,820
Available-for-sale, Gross unrealized losses, Recognized in OCI		282,843
Available-for-sale securities, Estimated fair value		1,238,820
Held-to-maturity Securities, Unrecognized Holding Gain	17,603	15,195
Held-to-maturity Securities, Unrecognized Holding Loss	1,225	1,308
Other [Member] | Asset-Backed Securities [Member]
Investment [Line Items]
Available-for-sale debt securities, Amortized cost	1,462
Available-For-Sale Debt Securities, Gross Unrealized Gains, Recognized In O C I	290
Available-For-Sale Debt Securities, Gross Unrealized Losses, Recognized In O C I	0
Available-For-Sale Securities, Debt Securities, Net Carrying Amount	1,752
Available-for-sale debt securities, Estimated fair value	1,752
Available-for-sale Securities, Gross Unrealized Gain		359
Available-for-sale equity securities, Amortized cost		27,540
Available-for-sale equity securities, Carrying value		27,899
Available-for-sale, Gross unrealized losses, Recognized in OCI		0
Available-for-sale securities, Estimated fair value		27,899
Other Debt Securities [Member] | Asset-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity, fair value	100	100
Held-to-maturity, Amortized cost	100	100
Held To Maturity Securities Gross Unrealized Gains	0
Held To Maturity Securities Gross Unrealized Gains Losses 1		0
Held To Maturity Securities Gross Unrealized Losses	0
Held To Maturity Securities Gross Unrealized Losses 1		0
Held-to-maturity, Carrying value	100	100
Held-to-maturity Securities, Unrecognized Holding Gain	0	0
Held-to-maturity Securities, Unrecognized Holding Loss	0	0
U.S. Treasury Securities [Member]
Investment [Line Items]
Available-for-sale debt securities, Amortized cost	1,471	1,442
Available-For-Sale Debt Securities, Gross Unrealized Gains, Recognized In O C I	75
Available-For-Sale Debt Securities, Gross Unrealized Losses, Recognized In O C I	0
Available-For-Sale Securities, Debt Securities, Net Carrying Amount	1,546	1,546
Available-for-sale debt securities, Estimated fair value	1,546	1,546
Available-for-sale Securities, Gross Unrealized Gain		104
Available-for-sale, Gross unrealized losses, Recognized in OCI		0
Agency Securities [Member]
Investment [Line Items]
Available-for-sale debt securities, Amortized cost	561,153	517,905
Available-For-Sale Debt Securities, Gross Unrealized Gains, Recognized In O C I	2,595
Available-For-Sale Debt Securities, Gross Unrealized Losses, Recognized In O C I	5,997
Available-For-Sale Securities, Debt Securities, Net Carrying Amount	557,751	518,924
Available-for-sale debt securities, Estimated fair value	557,751	518,924
Available-for-sale Securities, Gross Unrealized Gain		1,920
Available-for-sale, Gross unrealized losses, Recognized in OCI		901
Agency Guaranteed Mortgage-Backed Securities [Member]
Investment [Line Items]
Available-for-sale debt securities, Amortized cost	301,020	308,687
Available-For-Sale Debt Securities, Gross Unrealized Gains, Recognized In O C I	10,662
Available-For-Sale Debt Securities, Gross Unrealized Losses, Recognized In O C I	844
Available-For-Sale Securities, Debt Securities, Net Carrying Amount	310,838	317,376
Available-for-sale debt securities, Estimated fair value	310,838	317,376
Available-for-sale Securities, Gross Unrealized Gain		9,926
Available-for-sale, Gross unrealized losses, Recognized in OCI		1,237
Small Business Administration Loan-Backed Securities [Member]
Investment [Line Items]
Available-for-sale debt securities, Amortized cost	1,366,783	1,202,901
Available-For-Sale Debt Securities, Gross Unrealized Gains, Recognized In O C I	19,964
Available-For-Sale Debt Securities, Gross Unrealized Losses, Recognized In O C I	4,868
Available-For-Sale Securities, Debt Securities, Net Carrying Amount	1,381,879	1,221,259
Available-for-sale debt securities, Estimated fair value	1,381,879	1,221,259
Available-for-sale Securities, Gross Unrealized Gain		21,129
Available-for-sale, Gross unrealized losses, Recognized in OCI		2,771
Trust Preferred Securities - Real Estate Investment Trusts [Member] | Asset-Backed Securities [Member]
Investment [Line Items]
Available-for-sale Securities, Gross Unrealized Gain		0
Available-for-sale equity securities, Amortized cost		22,996
Available-for-sale equity securities, Carrying value		22,996
Available-for-sale, Gross unrealized losses, Recognized in OCI		0
Available-for-sale securities, Estimated fair value		22,996
Auction Rate Securities [Member] | Asset-Backed Securities [Member]
Investment [Line Items]
Available-for-sale debt securities, Amortized cost	6,508
Available-For-Sale Debt Securities, Gross Unrealized Gains, Recognized In O C I	87
Available-For-Sale Debt Securities, Gross Unrealized Losses, Recognized In O C I	35
Available-For-Sale Securities, Debt Securities, Net Carrying Amount	6,560
Available-for-sale debt securities, Estimated fair value	6,560
Available-for-sale Securities, Gross Unrealized Gain		118
Available-for-sale equity securities, Amortized cost		6,507
Available-for-sale equity securities, Carrying value		6,599
Available-for-sale, Gross unrealized losses, Recognized in OCI		26
Available-for-sale securities, Estimated fair value		6,599
Mutual Funds And Other [Member]
Investment [Line Items]
Available-for-sale Securities, Gross Unrealized Gain		21
Available-for-sale, Amortized cost		287,603
Available-for-sale, Gross unrealized losses, Recognized in OCI		7,421
Carrying value		280,203
Available-for-sale securities, Estimated fair value		280,203
Mutual Funds And Stock [Member]
Investment [Line Items]
Available-for-sale Securities, Gross Unrealized Gain	180
Available-for-sale, Amortized cost	257,643
Available-for-sale, Gross unrealized losses, Recognized in OCI	5,761
Carrying value	252,062
Available-for-sale securities, Estimated fair value	$ 252,062