Loans And Allowance For Loan Losses (Summary Of Activity In The Allowance For Loan Losses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	$ 184,532	$ 197,538
Provision	8,165	15,789
Loans charged off	15,917	23,389
Less recoveries on loans	4,752	4,600
Net loans charged off	11,165	18,789
Balance at end of period	181,532	194,538
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	122,497	119,946
Provision	(3,198)	13,465
Loans charged off	2,528	6,364
Less recoveries on loans	703	1,304
Net loans charged off	1,825	5,060
Balance at end of period	117,474	128,351
Personal Banking [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	62,035	77,592
Provision	11,363	2,324
Loans charged off	13,389	17,025
Less recoveries on loans	4,049	3,296
Net loans charged off	9,340	13,729
Balance at end of period	$ 64,058	$ 66,187