Loans And Allowance For Credit Losses (Summary Of Outstanding Loan Balances (Accruing And Nonaccruing) Categorized By Credit Quality Indicators) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable, Allowance for Credit Losses [Line Items]
Commercial and industrial	$ 12,481,083	$ 11,256,945
Leasing	387,929	422,513
Commercial Lending Loans - Owner Occupied	7,437,195	7,589,082
Loans and Leases Receivable, Gross, Commercial, Governments	449,418	494,183
Loans and Leases Receivable, Gross, Commercial	20,755,625	19,762,723
Loans Receivable Commercial Construction and Land Development	2,182,821	1,939,413
Term	8,005,837	8,062,819
Loans Receivable, Gross, Commercial, Real Estate	10,188,658	10,002,232
Loans and Leases Receivable, Gross, Consumer, Home Equity	2,133,120	2,177,680
1-4 family residential	4,736,665	4,350,329
Loans and Leases Receivable, Gross, Consumer, Construction	324,922	321,235
Loans and Leases Receivable, Gross, Consumer, Revolving, Credit Card	356,240	306,428
Loans and Leases Receivable, Gross, Consumer, Other	197,864	216,379
Loans and Leases Receivable, Gross, Consumer	7,748,811	7,372,051
FDIC-supported loans	350,271	528,241
Loans and Leases Receivable, Gross	39,043,365	37,665,247
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Commercial and industrial	12,481,083
Leasing	387,929
Commercial Lending Loans - Owner Occupied	7,437,195
Loans and Leases Receivable, Gross, Commercial, Governments	449,418
Loans and Leases Receivable, Gross, Commercial	20,755,625
Loans and Leases Receivable, Gross	20,755,625	19,762,723
Construction And Land Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Receivable Commercial Construction and Land Development	2,182,821
Loans and Leases Receivable, Gross	2,182,821	1,939,413
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Term	8,005,837
Loans Receivable, Gross, Commercial, Real Estate	10,188,658
Loans and Leases Receivable, Gross	10,188,658	10,002,232
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity	2,133,120
1-4 family residential	4,736,665
Loans and Leases Receivable, Gross, Consumer, Construction	324,922
Loans and Leases Receivable, Gross, Consumer, Revolving, Credit Card	356,240
Loans and Leases Receivable, Gross, Consumer, Other	197,864
Loans and Leases Receivable, Gross, Consumer	7,748,811
Loans and Leases Receivable, Gross	7,748,811	7,372,051
FDIC-Supported Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Gross	350,271	528,241
F D I C Supported Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
FDIC-supported loans	350,271
Pass [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Commercial and industrial		10,717,594
Leasing		419,482
Commercial Lending Loans - Owner Occupied		6,833,923
Loans and Leases Receivable, Gross, Commercial, Governments		453,193
Loans and Leases Receivable, Gross, Commercial		18,424,192
Loans Receivable Commercial Construction and Land Development		1,648,215
Term		7,433,789
Loans Receivable, Gross, Commercial, Real Estate		9,082,004
Loans and Leases Receivable, Gross, Consumer, Home Equity		2,138,693
1-4 family residential		4,234,426
Loans and Leases Receivable, Gross, Consumer, Construction		313,499
Loans and Leases Receivable, Gross, Consumer, Revolving, Credit Card		298,665
Loans and Leases Receivable, Gross, Consumer, Other		209,293
Loans and Leases Receivable, Gross, Consumer		7,194,576
FDIC-supported loans		327,609
Loans and Leases Receivable, Gross	37,009,767	35,028,381
Pass [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Commercial and industrial	11,807,825
Leasing	380,268
Commercial Lending Loans - Owner Occupied	6,827,464
Loans and Leases Receivable, Gross, Commercial, Governments	439,432
Loans and Leases Receivable, Gross, Commercial	19,454,989
Pass [Member] | Construction And Land Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Receivable Commercial Construction and Land Development	2,107,828
Pass [Member] | Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Term	7,569,472
Loans Receivable, Gross, Commercial, Real Estate	9,677,300
Pass [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity	2,111,475
1-4 family residential	4,668,841
Loans and Leases Receivable, Gross, Consumer, Construction	313,881
Loans and Leases Receivable, Gross, Consumer, Revolving, Credit Card	353,618
Loans and Leases Receivable, Gross, Consumer, Other	196,770
Loans and Leases Receivable, Gross, Consumer	7,644,585
Pass [Member] | F D I C Supported Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
FDIC-supported loans	232,893
Special Mention [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Commercial and industrial		198,645
Leasing		226
Commercial Lending Loans - Owner Occupied		138,539
Loans and Leases Receivable, Gross, Commercial, Governments		31,756
Loans and Leases Receivable, Gross, Commercial		369,166
Loans Receivable Commercial Construction and Land Development		57,348
Term		237,201
Loans Receivable, Gross, Commercial, Real Estate		294,549
Loans and Leases Receivable, Gross, Consumer, Home Equity		85
1-4 family residential		4,316
Loans and Leases Receivable, Gross, Consumer, Construction		218
Loans and Leases Receivable, Gross, Consumer, Revolving, Credit Card		23
Loans and Leases Receivable, Gross, Consumer, Other		3,211
Loans and Leases Receivable, Gross, Consumer		7,853
FDIC-supported loans		24,980
Loans and Leases Receivable, Gross	700,374	696,548
Special Mention [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Commercial and industrial	303,598
Leasing	2,050
Commercial Lending Loans - Owner Occupied	184,328
Loans and Leases Receivable, Gross, Commercial, Governments	0
Loans and Leases Receivable, Gross, Commercial	489,976
Special Mention [Member] | Construction And Land Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Receivable Commercial Construction and Land Development	15,010
Special Mention [Member] | Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Term	172,856
Loans Receivable, Gross, Commercial, Real Estate	187,866
Special Mention [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity	0
1-4 family residential	0
Loans and Leases Receivable, Gross, Consumer, Construction	0
Loans and Leases Receivable, Gross, Consumer, Revolving, Credit Card	0
Loans and Leases Receivable, Gross, Consumer, Other	0
Loans and Leases Receivable, Gross, Consumer	0
Special Mention [Member] | F D I C Supported Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
FDIC-supported loans	22,532
Sub-Standard [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Commercial and industrial		336,230
Leasing		2,805
Commercial Lending Loans - Owner Occupied		612,011
Loans and Leases Receivable, Gross, Commercial, Governments		9,234
Loans and Leases Receivable, Gross, Commercial		960,280
Loans Receivable Commercial Construction and Land Development		233,374
Term		388,914
Loans Receivable, Gross, Commercial, Real Estate		622,288
Loans and Leases Receivable, Gross, Consumer, Home Equity		38,897
1-4 family residential		111,063
Loans and Leases Receivable, Gross, Consumer, Construction		7,518
Loans and Leases Receivable, Gross, Consumer, Revolving, Credit Card		7,740
Loans and Leases Receivable, Gross, Consumer, Other		3,875
Loans and Leases Receivable, Gross, Consumer		169,093
FDIC-supported loans		175,652
Loans and Leases Receivable, Gross	1,323,955	1,927,313
Sub-Standard [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Commercial and industrial	360,391
Leasing	5,611
Commercial Lending Loans - Owner Occupied	425,403
Loans and Leases Receivable, Gross, Commercial, Governments	9,986
Loans and Leases Receivable, Gross, Commercial	801,391
Sub-Standard [Member] | Construction And Land Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Receivable Commercial Construction and Land Development	59,983
Sub-Standard [Member] | Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Term	263,509
Loans Receivable, Gross, Commercial, Real Estate	323,492
Sub-Standard [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity	21,645
1-4 family residential	67,824
Loans and Leases Receivable, Gross, Consumer, Construction	11,041
Loans and Leases Receivable, Gross, Consumer, Revolving, Credit Card	2,622
Loans and Leases Receivable, Gross, Consumer, Other	1,094
Loans and Leases Receivable, Gross, Consumer	104,226
Sub-Standard [Member] | F D I C Supported Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
FDIC-supported loans	94,846
Doubtful [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Commercial and industrial		4,476
Leasing		0
Commercial Lending Loans - Owner Occupied		4,609
Loans and Leases Receivable, Gross, Commercial, Governments		0
Loans and Leases Receivable, Gross, Commercial		9,085
Loans Receivable Commercial Construction and Land Development		476
Term		2,915
Loans Receivable, Gross, Commercial, Real Estate		3,391
Loans and Leases Receivable, Gross, Consumer, Home Equity		5
1-4 family residential		524
Loans and Leases Receivable, Gross, Consumer, Construction		0
Loans and Leases Receivable, Gross, Consumer, Revolving, Credit Card		0
Loans and Leases Receivable, Gross, Consumer, Other		0
Loans and Leases Receivable, Gross, Consumer		529
FDIC-supported loans		0
Loans and Leases Receivable, Gross	9,269	13,005
Doubtful [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Commercial and industrial	9,269
Leasing	0
Commercial Lending Loans - Owner Occupied	0
Loans and Leases Receivable, Gross, Commercial, Governments	0
Loans and Leases Receivable, Gross, Commercial	9,269
Doubtful [Member] | Construction And Land Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Receivable Commercial Construction and Land Development	0
Doubtful [Member] | Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Term	0
Loans Receivable, Gross, Commercial, Real Estate	0
Doubtful [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Gross, Consumer, Home Equity	0
1-4 family residential	0
Loans and Leases Receivable, Gross, Consumer, Construction	0
Loans and Leases Receivable, Gross, Consumer, Revolving, Credit Card	0
Loans and Leases Receivable, Gross, Consumer, Other	0
Loans and Leases Receivable, Gross, Consumer	0
Doubtful [Member] | F D I C Supported Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
FDIC-supported loans	0
Total Allowance [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Gross, Commercial		510,908
Loans Receivable, Gross, Commercial, Real Estate		276,976
Loans and Leases Receivable, Gross, Consumer		95,656
FDIC-supported loans		12,547
Loans and Leases Receivable, Gross	746,291	896,087
Total Allowance [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Gross, Commercial	465,145
Total Allowance [Member] | Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Receivable, Gross, Commercial, Real Estate	213,363
Total Allowance [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Gross, Consumer	60,865
Total Allowance [Member] | F D I C Supported Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
FDIC-supported loans	$ 6,918