Allowance for Loan and Lease Loss and Credit Quality (Non-Accrual Loans And Leases and Loans and Leases Past Due) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 30-59 Days Past Due	$ 18,284	$ 10,252
60-89 Days Past Due	6,375	5,038
Greater Than 90 Days and Accruing	7,512	3,430
Total Past Due	32,171	18,720
Nonaccrual	52,041	31,891
Current	15,243,520	7,677,555
Total, Non-covered loans and leases	15,327,732	7,728,166
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total, Non-covered loans and leases	8,903,660	4,630,155
Non-owner Occupied Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 30-59 Days Past Due	452	3,618
60-89 Days Past Due	0	352
Greater Than 90 Days and Accruing	283	0
Total Past Due	735	3,970
Nonaccrual	8,957	9,193
Current	3,280,918	2,521,999
Total, Non-covered loans and leases	3,290,610	2,535,162
Owner Occupied Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 30-59 Days Past Due	2,304	1,320
60-89 Days Past Due	347	340
Greater Than 90 Days and Accruing	0	610
Total Past Due	2,651	2,270
Nonaccrual	8,292	6,204
Current	2,622,921	1,300,926
Total, Non-covered loans and leases	2,633,864	1,309,400
Multifamily [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 30-59 Days Past Due	0	0
60-89 Days Past Due	512	0
Greater Than 90 Days and Accruing	0	0
Total Past Due	512	0
Nonaccrual	300	935
Current	2,637,806	440,273
Total, Non-covered loans and leases	2,638,618	441,208
Construction & Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 30-59 Days Past Due	1,091	0
60-89 Days Past Due	0	0
Greater Than 90 Days and Accruing	0	0
Total Past Due	1,091	0
Nonaccrual	0	0
Current	257,631	248,686
Total, Non-covered loans and leases	258,722	248,686
Residential Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 30-59 Days Past Due	6,155	0
60-89 Days Past Due	0	0
Greater Than 90 Days and Accruing	0	0
Total Past Due	6,155	0
Nonaccrual	0	2,801
Current	75,691	92,898
Total, Non-covered loans and leases	81,846	95,699
Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total, Non-covered loans and leases	2,948,823	2,142,213
Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 30-59 Days Past Due	1,098	901
60-89 Days Past Due	242	1,436
Greater Than 90 Days and Accruing	3	0
Total Past Due	1,343	2,337
Nonaccrual	19,097	8,723
Current	1,082,547	775,504
Total, Non-covered loans and leases	1,102,987	786,564
LOC & Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 30-59 Days Past Due	1,637	619
60-89 Days Past Due	1,155	224
Greater Than 90 Days and Accruing	1,223	0
Total Past Due	4,015	843
Nonaccrual	8,825	1,222
Current	1,309,882	991,993
Total, Non-covered loans and leases	1,322,722	994,058
Leases and Equipment Finance [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 30-59 Days Past Due	1,482	2,202
60-89 Days Past Due	1,695	1,706
Greater Than 90 Days and Accruing	695	517
Total Past Due	3,872	4,425
Nonaccrual	5,084	2,813
Current	514,158	354,353
Total, Non-covered loans and leases	523,114	361,591
Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total, Non-covered loans and leases	3,086,213	903,423
Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 30-59 Days Past Due	8	1,050
60-89 Days Past Due	1,224	342
Greater Than 90 Days and Accruing	4,289	2,070
Total Past Due	5,521	3,462
Nonaccrual	655	0
Current	2,227,559	616,055
Total, Non-covered loans and leases	2,233,735	619,517
Home Equity Loans & Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 30-59 Days Past Due	1,924	473
60-89 Days Past Due	702	563
Greater Than 90 Days and Accruing	749	160
Total Past Due	3,375	1,196
Nonaccrual	615	0
Current	848,488	282,710
Total, Non-covered loans and leases	852,478	283,906
Consumer & Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 30-59 Days Past Due	2,133	69
60-89 Days Past Due	498	75
Greater Than 90 Days and Accruing	270	73
Total Past Due	2,901	217
Nonaccrual	216	0
Current	385,919	52,158
Total, Non-covered loans and leases	$ 389,036	$ 52,375