Fair Value Measurements (Details 3) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financial assets:
Cash and due from banks	$ 428,936	$ 339,438
Securities held to maturity	35,387	2,425
Loans, net	2,418,514	2,357,837
Financial liabilities:
Junior subordinated debt owed to unconsolidated trusts	55,000	55,000
Carrying Amount | Level 2
Financial assets:
Cash and due from banks	428,936	339,438
Securities held to maturity	35,037	2,373
Loans held for sale	18,685	10,400
Accrued interest receivable	12,491	11,187
Financial liabilities:
Deposits	3,183,885	2,900,848
Securities sold under agreements to repurchase	183,675	198,893
Long-term debt	50,000	50,000
Junior subordinated debt owed to unconsolidated trusts	55,000	55,000
Accrued interest payable	499	507
Carrying Amount | Level 3
Financial assets:
Loans, net	2,418,514	2,357,837
Fair Value | Level 2
Financial assets:
Cash and due from banks	428,936	339,438
Securities held to maturity	35,387	2,425
Loans held for sale	19,039	10,634
Accrued interest receivable	12,491	11,187
Financial liabilities:
Deposits	3,184,855	2,900,763
Securities sold under agreements to repurchase	183,675	198,893
Long-term debt	50,000	50,000
Junior subordinated debt owed to unconsolidated trusts	55,000	55,000
Accrued interest payable	499	507
Fair Value | Level 3
Financial assets:
Loans, net	$ 2,440,340	$ 2,360,000