Allowance for Loan and Lease Loss and Credit Quality (Non-Accrual Loans And Loans Past Due) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 78,205	$ 69,651
Non-Accrual	28,915	27,765
Current & Other	17,722,518	17,411,247
GNMA Loans past due by 90 days, but not yet repurchased	5,300
Loans by credit quality	17,829,638	17,508,663
Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current & Other	260,300	280,400
Greater than 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	31,716	12,587
60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	17,814	17,838
Greater than 90 Days and Accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	28,675	39,226
Commercial real estate | Non-owner occupied term, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	7,583	2,792
Non-Accrual	1,553	2,100
Current & Other	3,401,778	3,325,550
Loans by credit quality	3,410,914	3,330,442
Commercial real estate | Owner occupied term, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,562	5,514
Non-Accrual	8,000	4,391
Current & Other	2,573,621	2,589,150
Loans by credit quality	2,584,183	2,599,055
Commercial real estate | Multifamily, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,170	0
Non-Accrual	387	476
Current & Other	2,882,607	2,858,480
Loans by credit quality	2,885,164	2,858,956
Commercial real estate | Construction & development, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Non-Accrual	0	0
Current & Other	471,007	463,625
Loans by credit quality	471,007	463,625
Commercial real estate | Residential development, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Non-Accrual	0	0
Current & Other	145,479	142,984
Loans by credit quality	145,479	142,984
Commercial real estate | Greater than 30 to 59 Days Past Due | Non-owner occupied term, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	5,679	718
Commercial real estate | Greater than 30 to 59 Days Past Due | Owner occupied term, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	965	974
Commercial real estate | Greater than 30 to 59 Days Past Due | Multifamily, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,170	0
Commercial real estate | Greater than 30 to 59 Days Past Due | Construction & development, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Commercial real estate | Greater than 30 to 59 Days Past Due | Residential development, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Commercial real estate | 60 to 89 Days Past Due | Non-owner occupied term, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,863	1,027
Commercial real estate | 60 to 89 Days Past Due | Owner occupied term, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,597	4,539
Commercial real estate | 60 to 89 Days Past Due | Multifamily, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Commercial real estate | 60 to 89 Days Past Due | Construction & development, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Commercial real estate | 60 to 89 Days Past Due | Residential development, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Commercial real estate | Greater than 90 Days and Accruing | Non-owner occupied term, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	41	1,047
Commercial real estate | Greater than 90 Days and Accruing | Owner occupied term, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	1
Commercial real estate | Greater than 90 Days and Accruing | Multifamily, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Commercial real estate | Greater than 90 Days and Accruing | Construction & development, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Commercial real estate | Greater than 90 Days and Accruing | Residential development, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Commercial | Term, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	215	552
Non-Accrual	6,782	6,880
Current & Other	1,613,314	1,501,348
Loans by credit quality	1,620,311	1,508,780
Commercial | LOC & other, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	11,152	1,700
Non-Accrual	3,162	4,998
Current & Other	1,099,846	1,109,561
Loans by credit quality	1,114,160	1,116,259
Commercial | Leases and equipment finance, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	14,886	14,016
Non-Accrual	9,031	8,920
Current & Other	976,459	927,652
Loans by credit quality	1,000,376	950,588
Commercial | Greater than 30 to 59 Days Past Due | Term, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1	319
Commercial | Greater than 30 to 59 Days Past Due | LOC & other, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	4,095	1,673
Commercial | Greater than 30 to 59 Days Past Due | Leases and equipment finance, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	10,001	5,343
Commercial | 60 to 89 Days Past Due | Term, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	233
Commercial | 60 to 89 Days Past Due | LOC & other, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	6,885	27
Commercial | 60 to 89 Days Past Due | Leases and equipment finance, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	4,885	6,865
Commercial | Greater than 90 Days and Accruing | Term, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	214	0
Commercial | Greater than 90 Days and Accruing | LOC & other, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	172	0
Commercial | Greater than 90 Days and Accruing | Leases and equipment finance, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	1,808
Residential | Mortgage, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	31,180	36,827
Non-Accrual	0	0
Current & Other	2,885,744	2,851,144
Loans by credit quality	2,916,924	2,887,971
Residential | Home equity loans & lines, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	4,222	3,217
Non-Accrual	0	0
Current & Other	1,010,916	1,008,627
Loans by credit quality	1,015,138	1,011,844
Residential | Greater than 30 to 59 Days Past Due | Mortgage, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	4,716	10
Residential | Greater than 30 to 59 Days Past Due | Home equity loans & lines, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,552	289
Residential | 60 to 89 Days Past Due | Mortgage, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,284	3,114
Residential | 60 to 89 Days Past Due | Home equity loans & lines, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	522	848
Residential | Greater than 90 Days and Accruing | Mortgage, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	25,180	33,703
Residential | Greater than 90 Days and Accruing | Mortgage, net | GNMA Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
GNMA Loans past due by 90 days, but not yet repurchased	5,300	10,900
Residential | Greater than 90 Days and Accruing | Home equity loans & lines, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,148	2,080
Consumer & other, net
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	4,235	5,033
Non-Accrual	0	0
Current & Other	661,747	633,126
Loans by credit quality	665,982	638,159
Consumer & other, net | Greater than 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,537	3,261
Consumer & other, net | 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	778	1,185
Consumer & other, net | Greater than 90 Days and Accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 920	$ 587