Loans and Allowance for Loan Losses (Details 2) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011
Summary of amounts included in nonaccrual loans segregated by class of loans
Nonaccrual loans, Total	$ 22,101	$ 21,187	$ 24,088
Non-residential real estate [Member]
Summary of amounts included in nonaccrual loans segregated by class of loans
Nonaccrual loans, Total	9,324
Residential real estate [Member]
Summary of amounts included in nonaccrual loans segregated by class of loans
Nonaccrual loans, Total	4,179
Non-consumer non-real estate [Member]
Summary of amounts included in nonaccrual loans segregated by class of loans
Nonaccrual loans, Total	2,527
Consumer non-real estate [Member]
Summary of amounts included in nonaccrual loans segregated by class of loans
Nonaccrual loans, Total	138
Other loans [Member]
Summary of amounts included in nonaccrual loans segregated by class of loans
Nonaccrual loans, Total	2,221
Acquired loans [Member]
Summary of amounts included in nonaccrual loans segregated by class of loans
Nonaccrual loans, Total	$ 3,712