Financial Instruments (Details) (USD $)	Jun. 30, 2013	Dec. 31, 2012
Level 1
Financial assets:
Cash and cash equivalents	$ 32,808,000	$ 138,396,000
Investment securities	137,000	133,000
Loans and loans held-for-sale, net	0	0
Accrued interest receivable	0	0
Federal Home Loan Bank stock	0	0
Financial liabilities:
Demand deposits, NOW, savings and money market accounts	0	0
Time deposits	0	0
Borrowed funds	0	0
Accrued interest payable	0	0
Level 1 | Forward Sales Commitments
Financial assets:
Derivative assets	0
Financial liabilities:
Derivative liabilities		0
Level 1 | Interest Rate Swap Agreements
Financial assets:
Derivative assets	0	0
Financial liabilities:
Derivative liabilities	0	0
Level 1 | Interest Rate Lock Commitments
Financial assets:
Derivative assets		0
Financial liabilities:
Derivative liabilities	0
Level 2
Financial assets:
Cash and cash equivalents	0	0
Investment securities	330,208,000	342,987,000
Loans and loans held-for-sale, net	0	0
Accrued interest receivable	2,028,000	1,760,000
Federal Home Loan Bank stock	3,473,000	4,154,000
Financial liabilities:
Demand deposits, NOW, savings and money market accounts	916,773,000	898,372,000
Time deposits	588,397,000	742,552,000
Borrowed funds	92,512,000	105,926,000
Accrued interest payable	999,000	1,629,000
Level 2 | Forward Sales Commitments
Financial assets:
Derivative assets	612,000
Financial liabilities:
Derivative liabilities		481,000
Level 2 | Interest Rate Swap Agreements
Financial assets:
Derivative assets	0	0
Financial liabilities:
Derivative liabilities	0	0
Level 2 | Interest Rate Lock Commitments
Financial assets:
Derivative assets		0
Financial liabilities:
Derivative liabilities	0
Level 3
Financial assets:
Cash and cash equivalents	0	0
Investment securities	0	0
Loans and loans held-for-sale, net	1,186,481,000	1,187,663,000
Accrued interest receivable	4,518,000	4,616,000
Federal Home Loan Bank stock	0	0
Financial liabilities:
Demand deposits, NOW, savings and money market accounts	0	0
Time deposits	0	0
Borrowed funds	0	0
Accrued interest payable	0	0
Level 3 | Forward Sales Commitments
Financial assets:
Derivative assets	0
Financial liabilities:
Derivative liabilities		0
Level 3 | Interest Rate Swap Agreements
Financial assets:
Derivative assets	154,000	196,000
Financial liabilities:
Derivative liabilities	154,000	196,000
Level 3 | Interest Rate Lock Commitments
Financial assets:
Derivative assets		873,000
Financial liabilities:
Derivative liabilities	312,000
Carrying Amount
Financial assets:
Cash and cash equivalents	32,808,000	138,396,000
Investment securities	330,345,000	343,120,000
Loans and loans held-for-sale, net	1,314,382,000	1,312,034,000
Accrued interest receivable	6,546,000	6,376,000
Federal Home Loan Bank stock	3,473,000	4,154,000
Financial liabilities:
Demand deposits, NOW, savings and money market accounts	939,056,000	898,372,000
Time deposits	584,041,000	733,290,000
Borrowed funds	91,896,000	105,136,000
Accrued interest payable	999,000	1,629,000
Carrying Amount | Forward Sales Commitments
Financial assets:
Derivative assets	612,000
Financial liabilities:
Derivative liabilities		481,000
Carrying Amount | Interest Rate Swap Agreements
Financial assets:
Derivative assets	154,000	196,000
Financial liabilities:
Derivative liabilities	154,000	196,000
Carrying Amount | Interest Rate Lock Commitments
Financial assets:
Derivative assets		873,000
Financial liabilities:
Derivative liabilities	312
Estimated Fair Value
Financial assets:
Cash and cash equivalents	32,808,000	138,396,000
Investment securities	330,345,000	343,120,000
Loans and loans held-for-sale, net	1,186,481,000	1,187,663,000
Accrued interest receivable	6,546,000	6,376,000
Federal Home Loan Bank stock	3,473,000	4,154,000
Financial liabilities:
Demand deposits, NOW, savings and money market accounts	916,773,000	898,372,000
Time deposits	588,397,000	742,552,000
Borrowed funds	92,512,000	105,926,000
Accrued interest payable	999,000	1,629,000
Estimated Fair Value | Forward Sales Commitments
Financial assets:
Derivative assets	612,000
Financial liabilities:
Derivative liabilities		481,000
Estimated Fair Value | Interest Rate Swap Agreements
Financial assets:
Derivative assets	154,000	196,000
Financial liabilities:
Derivative liabilities	154,000	196,000
Estimated Fair Value | Interest Rate Lock Commitments
Financial assets:
Derivative assets		873,000
Financial liabilities:
Derivative liabilities	$ 312