Allowance for Loan and Lease Loss and Credit Quality (Non-Accrual Loans And Loans Past Due) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days and Accruing	$ 13,529	$ 7,512
Total Past Due	39,082	32,171
Nonaccrual	33,572	52,041
Current	15,901,543	15,243,520
Total loans and leases, net of deferred fees and costs	15,974,197	15,327,732	$ 15,136,455
Purchased impaired non-covered loans	485,700	562,900
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases, net of deferred fees and costs	9,112,131		9,097,518
Non-owner Occupied Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days and Accruing	1,704	283
Total Past Due	4,912	735
Nonaccrual	2,067	8,957
Current	3,287,380	3,280,918
Total loans and leases, net of deferred fees and costs	3,294,359	3,290,610
Owner Occupied Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days and Accruing	681	0
Total Past Due	3,758	2,651
Nonaccrual	5,354	8,292
Current	2,627,688	2,622,921
Total loans and leases, net of deferred fees and costs	2,636,800	2,633,864
Multifamily [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days and Accruing	0	0
Total Past Due	3,284	512
Nonaccrual	0	300
Current	2,856,600	2,637,806
Total loans and leases, net of deferred fees and costs	2,859,884	2,638,618
Construction & Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days and Accruing	0	0
Total Past Due	0	1,091
Nonaccrual	0	0
Current	244,354	257,631
Total loans and leases, net of deferred fees and costs	244,354	258,722
Residential Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days and Accruing	0	0
Total Past Due	0	6,155
Nonaccrual	0	0
Current	76,734	75,691
Total loans and leases, net of deferred fees and costs	76,734	81,846
Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases, net of deferred fees and costs	2,987,120		2,908,870
Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days and Accruing	0	3
Total Past Due	1,456	1,343
Nonaccrual	20,325	19,097
Current	1,352,747	1,375,649
Total loans and leases, net of deferred fees and costs	1,374,528	1,396,089
LOC & Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days and Accruing	44	1,223
Total Past Due	1,973	4,015
Nonaccrual	1,455	8,825
Current	978,469	1,016,780
Total loans and leases, net of deferred fees and costs	981,897	1,029,620
Leases and Equipment Finance [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days and Accruing	614	695
Total Past Due	4,595	3,872
Nonaccrual	3,372	5,084
Current	622,728	514,158
Total loans and leases, net of deferred fees and costs	630,695	523,114
Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases, net of deferred fees and costs	3,415,638		2,794,325
Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days and Accruing	9,007	4,289
Total Past Due	11,269	5,521
Nonaccrual	460	655
Current	2,521,313	2,227,559
Total loans and leases, net of deferred fees and costs	2,533,042	2,233,735
Home Equity Loans & Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days and Accruing	1,036	749
Total Past Due	4,160	3,375
Nonaccrual	431	615
Current	878,005	848,488
Total loans and leases, net of deferred fees and costs	882,596	852,478
Consumer & Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days and Accruing	443	270
Total Past Due	3,675	2,901
Nonaccrual	108	216
Current	455,525	385,919
Total loans and leases, net of deferred fees and costs	459,308	389,036	$ 335,742
Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	12,824	18,284
Financing Receivables, 30 to 59 Days Past Due [Member] | Non-owner Occupied Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,505	452
Financing Receivables, 30 to 59 Days Past Due [Member] | Owner Occupied Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,830	2,304
Financing Receivables, 30 to 59 Days Past Due [Member] | Multifamily [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	293	0
Financing Receivables, 30 to 59 Days Past Due [Member] | Construction & Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	1,091
Financing Receivables, 30 to 59 Days Past Due [Member] | Residential Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	6,155
Financing Receivables, 30 to 59 Days Past Due [Member] | Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,217	1,098
Financing Receivables, 30 to 59 Days Past Due [Member] | LOC & Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,151	1,637
Financing Receivables, 30 to 59 Days Past Due [Member] | Leases and Equipment Finance [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,723	1,482
Financing Receivables, 30 to 59 Days Past Due [Member] | Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	171	8
Financing Receivables, 30 to 59 Days Past Due [Member] | Home Equity Loans & Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,504	1,924
Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer & Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,430	2,133
Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	12,729	6,375
Financing Receivables, 60 to 89 Days Past Due [Member] | Non-owner Occupied Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,703	0
Financing Receivables, 60 to 89 Days Past Due [Member] | Owner Occupied Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,247	347
Financing Receivables, 60 to 89 Days Past Due [Member] | Multifamily [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,991	512
Financing Receivables, 60 to 89 Days Past Due [Member] | Construction & Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Financing Receivables, 60 to 89 Days Past Due [Member] | Residential Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Financing Receivables, 60 to 89 Days Past Due [Member] | Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	239	242
Financing Receivables, 60 to 89 Days Past Due [Member] | LOC & Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	778	1,155
Financing Receivables, 60 to 89 Days Past Due [Member] | Leases and Equipment Finance [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,258	1,695
Financing Receivables, 60 to 89 Days Past Due [Member] | Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,091	1,224
Financing Receivables, 60 to 89 Days Past Due [Member] | Home Equity Loans & Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	620	702
Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer & Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 802	$ 498