Loans And Allowance For Loan Losses (Allowance For Loan Losses And Related Loan Balance Disaggregated On The Basis Of Impairment Methodology) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Loans And Allowance For Loan Losses [Line Items]
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	$ 11,113,639	$ 10,849,200
Impaired Financing Receivable, Recorded Investment	108,399	107,636
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	151,776	150,632
Impaired Financing Receivable, Related Allowance	9,756	10,900
Commercial Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	6,600,903	6,356,550
Impaired Financing Receivable, Recorded Investment	79,325	78,516
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	90,244	85,713
Impaired Financing Receivable, Related Allowance	7,637	8,476
Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	4,512,736	4,492,650
Impaired Financing Receivable, Recorded Investment	29,074	29,120
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	61,532	64,919
Impaired Financing Receivable, Related Allowance	$ 2,119	$ 2,424