Loans and Leases and the Allowance for Loan and Lease Losses (Details 3) (USD $) In Thousands, unless otherwise specified																																																								3 Months Ended											3 Months Ended		3 Months Ended		3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Mar. 31, 2013 Commercial	Dec. 31, 2012 Commercial	Mar. 31, 2012 Commercial	Mar. 31, 2013 Commercial and Industrial	Dec. 31, 2012 Commercial and Industrial	Mar. 31, 2013 Commercial Mortgage	Dec. 31, 2012 Commercial Mortgage	Mar. 31, 2013 Construction	Dec. 31, 2012 Construction	Mar. 31, 2013 Lease Financing	Dec. 31, 2012 Lease Financing	Mar. 31, 2013 Consumer	Dec. 31, 2012 Consumer	Mar. 31, 2012 Consumer	Mar. 31, 2013 Residential Mortgage	Dec. 31, 2012 Residential Mortgage	Mar. 31, 2013 Home Equity	Dec. 31, 2012 Home Equity	Mar. 31, 2013 Automobile	Dec. 31, 2012 Automobile	Mar. 31, 2013 Other	Dec. 31, 2012 Other	Mar. 31, 2013 Pass Commercial	Dec. 31, 2012 Pass Commercial	Mar. 31, 2013 Pass Commercial and Industrial	Dec. 31, 2012 Pass Commercial and Industrial	Mar. 31, 2013 Pass Commercial Mortgage	Dec. 31, 2012 Pass Commercial Mortgage	Mar. 31, 2013 Pass Construction	Dec. 31, 2012 Pass Construction	Mar. 31, 2013 Pass Lease Financing	Dec. 31, 2012 Pass Lease Financing	Mar. 31, 2013 Pass Consumer	Dec. 31, 2012 Pass Consumer	Mar. 31, 2013 Pass Residential Mortgage	Dec. 31, 2012 Pass Residential Mortgage	Mar. 31, 2013 Pass Home Equity	Dec. 31, 2012 Pass Home Equity	Mar. 31, 2013 Pass Automobile	Dec. 31, 2012 Pass Automobile	Mar. 31, 2013 Pass Other	Dec. 31, 2012 Pass Other	Mar. 31, 2013 Special Mention Commercial	Dec. 31, 2012 Special Mention Commercial	Mar. 31, 2013 Special Mention Commercial and Industrial	Dec. 31, 2012 Special Mention Commercial and Industrial	Mar. 31, 2013 Special Mention Commercial Mortgage	Dec. 31, 2012 Special Mention Commercial Mortgage	Mar. 31, 2013 Special Mention Construction	Dec. 31, 2012 Special Mention Construction	Mar. 31, 2013 Special Mention Lease Financing	Dec. 31, 2012 Special Mention Lease Financing	Mar. 31, 2013 Classified M	Mar. 31, 2013 Classified Commercial	Dec. 31, 2012 Classified Commercial	Mar. 31, 2013 Classified Commercial and Industrial	Dec. 31, 2012 Classified Commercial and Industrial	Mar. 31, 2013 Classified Commercial Mortgage	Dec. 31, 2012 Classified Commercial Mortgage	Mar. 31, 2013 Classified Construction	Dec. 31, 2012 Classified Construction	Mar. 31, 2013 Classified Lease Financing	Dec. 31, 2012 Classified Lease Financing	Mar. 31, 2013 Classified Consumer D	Dec. 31, 2012 Classified Consumer	Mar. 31, 2013 Classified Residential Mortgage D	Dec. 31, 2012 Classified Residential Mortgage	Mar. 31, 2013 Classified Home Equity D	Dec. 31, 2012 Classified Home Equity	Mar. 31, 2013 Classified Automobile	Dec. 31, 2012 Classified Automobile	Mar. 31, 2013 Classified Other	Dec. 31, 2012 Classified Other
Recorded investment in loans and leases by class and by credit quality indicator
Number of days past due for loans and leases in classified credit quality indicator																																																																			90		90		90
Maximum current loan-to-value ratio for residential mortgage and home equity loans to be considered as pass (as a percent)																																																																					60.00%		60.00%
Number of months up to which residential and home equity loans may be considered classified, even if they are current as to principal and interest																																																								6
Total Recorded Investment in Loans and Leases	$ 5,782,969	$ 5,854,521	$ 5,598,932	$ 2,326,423	$ 2,315,893	$ 2,132,958	$ 834,801	$ 829,512	$ 1,104,718	$ 1,097,425	$ 117,797	$ 113,987	$ 269,107	$ 274,969	$ 3,456,546	$ 3,538,628	$ 3,465,974	$ 2,275,209	$ 2,349,916	$ 757,877	$ 770,376	$ 220,362	$ 209,832	$ 203,098	$ 208,504	$ 2,153,636	$ 2,141,241	$ 786,309	$ 779,654	$ 1,024,172	$ 1,018,128	$ 101,057	$ 96,058	$ 242,098	$ 247,401	$ 3,423,480	$ 3,510,691	$ 2,248,884	$ 2,326,216	$ 752,053	$ 766,912	$ 220,121	$ 209,646	$ 202,422	$ 207,917	$ 75,380	$ 88,986	$ 8,367	$ 22,759	$ 27,218	$ 23,848	$ 13,673	$ 15,839	$ 26,122	$ 26,540		$ 97,407	$ 85,666	$ 40,125	$ 27,099	$ 53,328	$ 55,449	$ 3,067	$ 2,090	$ 887	$ 1,028	$ 33,066	$ 27,937	$ 26,325	$ 23,700	$ 5,824	$ 3,464	$ 241	$ 186	$ 676	$ 587