Fair Value Measurements (Details 3) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Financial assets:
Cash and due from banks	$ 351,255	$ 315,053
Loans, net	1,985,095	1,977,589
Financial liabilities:
Junior subordinated debt owed to unconsolidated trusts	55,000	55,000
Carrying Amount | Level 2 Inputs
Financial assets:
Cash and due from banks	351,255	315,053
Loans held for sale, fair value	40,003	15,249
Accrued interest receivable	12,275	11,121
Financial liabilities:
Deposits	2,980,292	2,763,454
Securities sold under agreements to repurchase	139,024	127,867
Long-term debt	7,000	19,417
Junior subordinated debt owed to unconsolidated trusts	55,000	55,000
Accrued interest payable	1,128	1,881
Carrying Amount | Level 3 Inputs
Financial assets:
Loans, net	1,985,095	1,977,589
Fair Value | Level 2 Inputs
Financial assets:
Cash and due from banks	351,255	315,053
Loans held for sale, fair value	40,971	15,569
Accrued interest receivable	12,275	11,121
Financial liabilities:
Deposits	2,987,524	2,773,599
Securities sold under agreements to repurchase	139,024	127,867
Long-term debt	7,120	20,138
Junior subordinated debt owed to unconsolidated trusts	55,000	55,000
Accrued interest payable	1,128	1,881
Fair Value | Level 3 Inputs
Financial assets:
Loans, net	$ 2,006,588	$ 2,008,603