Loans And Leases (Summary Of The Recorded Investment Of Company's TDRs) (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2012	Dec. 31, 2011
Loans and Leases Receivable Disclosure [Abstract]
Accrual status	$ 363,083	$ 367,344
Non-accrual status	89,380	76,968
Total recorded investment	452,463	444,312
Accruing TDRs performing under modified terms more than one year	85.20%	76.00%
TDR specific reserves included in the balance of allowance for loan losses	30,703	44,847
Additional funds committed to borrowers in TDR status (a)	$ 4,417	$ 7,872

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Additional Funds Committed to Borrowers in Troubled Debt Restructuring Status

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Allowance for Loan and Lease Losses Related to Troubled Debt Restructurings

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Loans and Leases Receivable, Troubled Debt Restructurings, Recorded Investment.

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Loans and Leases Receivable, Troubled Debt Restructurings, Recorded Investment Accrual Status

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Loans and Leases Receivable, Troubled Debt Restructurings, Recorded Investment, Nonaccrual Status

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TDR Loans Performing In Accordance With Restructured Terms For More Than One Year Percentage

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