Loans and Leases (Aging Of The Outstanding Loans and Leases By Class Excluding Loans Impaired At Acquisition Date) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013		Dec. 31, 2012		Jun. 30, 2012
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	$ 277,601		$ 333,170		$ 308,041
Total Loans and Leases	11,655,469	[1]	11,576,115	[1]	11,462,458	[1]
Commercial Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	8,140,071		7,994,495		7,825,628
Commercial Mortgage | Construction and Land Development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	305,789		309,190		329,151
Commercial Mortgage | Other Commercial Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	176,031		160,980		162,579
Commercial Mortgage | Commercial and Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	997,504		1,038,530		989,341
Commercial Mortgage | Lease Financing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	352,818		330,679		320,703
Commercial Mortgage | Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	172,861		125,681		140,738
Non-Commercial Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	3,515,398		3,581,620		3,636,830
Non-Commercial Loans | Construction and Land Development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	119,253		131,992		127,726
Non-Commercial Loans | Residential Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	884,020		822,889		809,230
Non-Commercial Loans | Revolving Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	2,123,814		2,210,133		2,268,210
Non-Commercial Loans | Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	388,311		416,606		431,664
Originated Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	49,320		64,528		46,554
60-89 Days Past Due	10,422		19,620		14,129
90 Days or Greater	43,037		50,412		46,562
Total	102,779		134,560		107,245
Current	11,552,690		11,441,555		11,355,213
Total Loans and Leases	11,655,469		11,576,115		11,462,458
Originated Loans | Commercial Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	40,362		45,380		37,833
Current	6,094,706		5,984,055		5,845,283
Total Loans and Leases	6,135,068		6,029,435		5,883,116
Originated Loans | Lease Financing
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	512		991		305
60-89 Days Past Due	0		138		4
90 Days or Greater	265		621		530
Total	777		1,750		839
Current	352,041		328,929		319,864
Total Loans and Leases	352,818		330,679		320,703
Originated Loans | Commercial Mortgage | Construction and Land Development
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	552		927		1,430
60-89 Days Past Due	248		0		463
90 Days or Greater	6,961		7,878		8,663
Total	7,761		8,805		10,556
Current	298,028		300,385		318,595
Total Loans and Leases	305,789		309,190		329,151
Originated Loans | Commercial Mortgage | Commercial Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	20,970		21,075		15,830
60-89 Days Past Due	2,156		3,987		5,171
90 Days or Greater	17,236		20,318		16,832
Originated Loans | Commercial Mortgage | Other Commercial Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	112		387		284
60-89 Days Past Due	107		1,240		68
90 Days or Greater	265		1,034		551
Total	484		2,661		903
Current	175,547		158,319		161,676
Total Loans and Leases	176,031		160,980		162,579
Originated Loans | Commercial Mortgage | Commercial and Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	2,532		6,205		2,528
60-89 Days Past Due	2,495		1,288		882
90 Days or Greater	375		1,614		2,153
Total	5,402		9,107		5,563
Current	992,102		1,029,423		983,778
Total Loans and Leases	997,504		1,038,530		989,341
Originated Loans | Commercial Mortgage | Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	25		18		100
60-89 Days Past Due	0		13		0
90 Days or Greater	0		0		0
Total	25		31		100
Current	172,836		125,650		140,638
Total Loans and Leases	172,861		125,681		140,738
Originated Loans | Non-Commercial Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	3,515,398		3,581,620		3,636,830
Originated Loans | Non-Commercial Loans | Construction and Land Development
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	630		1,941		1,352
60-89 Days Past Due	8		490		447
90 Days or Greater	997		797		831
Total	1,635		3,228		2,630
Current	117,618		128,764		125,096
Total Loans and Leases	119,253		131,992		127,726
Originated Loans | Non-Commercial Loans | Residential Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	14,626		15,711		12,601
60-89 Days Past Due	2,427		7,559		3,659
90 Days or Greater	12,622		12,993		11,338
Total	29,675		36,263		27,598
Current	854,345		786,626		781,632
Total Loans and Leases	884,020		822,889		809,230
Originated Loans | Non-Commercial Loans | Revolving Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	7,587		12,868		10,131
60-89 Days Past Due	2,134		3,200		2,460
90 Days or Greater	3,679		3,879		4,191
Total	13,400		19,947		16,782
Current	2,110,414		2,190,186		2,251,428
Total Loans and Leases	2,123,814		2,210,133		2,268,210
Originated Loans | Non-Commercial Loans | Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	1,774		4,405		1,993
60-89 Days Past Due	847		1,705		975
90 Days or Greater	637		1,278		1,473
Total	3,258		7,388		4,441
Current	385,053		409,218		427,223
Total Loans and Leases	$ 388,311		$ 416,606		$ 431,664

[1] Derived from 2012 Annual Report on Form 10-K.