Fair Value of Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2013	Dec. 31, 2012
Derivatives, Fair Value [Line Items]
Cash and cash equivalents, Carrying Amount	$ 181,723	$ 225,262	$ 269,853	$ 141,088
Investment securities, Carrying Amount	327,469	317,767
Loans, net, Carrying Amount	653,850	640,498
Accrued interest receivable, Carrying Amount	6,180	6,030
Assets, Carrying Amount	1,169,222	1,189,557
Cash and cash equivalents, Fair Value	181,723	225,262
Loans, net, Fair Value	327,469	317,767
Investment securities, Fair Value	652,982	642,543
Accrued interest receivable, Fair Value	6,180	6,030
Assets, Fair Value	1,168,354	1,191,602
Deposits	551,511	582,496
Accounts and drafts payable	585,858	543,953
Accrued interest payable, Carrying Amount	70	88
Liabilities, Carrying Amount	1,137,439	1,126,537
Deposits, Fair Value	551,805	583,989
Accounts and drafts payable, Fair Value	585,858	543,953
Accrued interest payable, Fair Value	70	88
Liabilities, Fair Value	$ 1,137,733	$ 1,128,030