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	Jun. 30, 2016	Dec. 31, 2015
Loans And Allowance For Loan Losses [Line Items]
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	$ 13,020,695	$ 12,371,378
Impaired Financing Receivable, Recorded Investment	71,193	65,314
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	150,928	148,048
Impaired Financing Receivable, Related Allowance	2,904	3,484
Commercial Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	8,009,720	7,334,480
Impaired Financing Receivable, Recorded Investment	49,695	43,027
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	87,627	80,159
Impaired Financing Receivable, Related Allowance	1,571	1,927
Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	5,010,975	5,036,898
Impaired Financing Receivable, Recorded Investment	21,498	22,287
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	63,301	67,889
Impaired Financing Receivable, Related Allowance	$ 1,333	$ 1,557