Loans And Allowance For Credit Losses (Summary Of Activity In The Allowance For Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance at start of period	$ 160,682	$ 159,932
Provision	11,806	24,269
Loans charged off	14,458	29,189
Less recoveries on loans	3,152	6,170
Allowance for Loan and Lease Losses Write-offs, Net, Total	11,306	23,019
Balance at end of period	161,182	161,182
Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance at start of period	93,643	92,869
Provision	(1,666)	(498)
Loans charged off	419	946
Less recoveries on loans	250	383
Allowance for Loan and Lease Losses Write-offs, Net, Total	169	563
Balance at end of period	91,808	91,808
Personal Banking Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance at start of period	67,039	67,063
Provision	13,472	24,767
Loans charged off	14,039	28,243
Less recoveries on loans	2,902	5,787
Allowance for Loan and Lease Losses Write-offs, Net, Total	11,137	22,456
Balance at end of period	$ 69,374	$ 69,374