Fair Value of Financial Instruments - Estimated Fair Values and Related Carrying or Notional Amounts (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Financial Assets:
Cash and Cash Equivalents	$ 19,263	$ 44,092
Securities - available for sale	324,509	355,905
Other Securities	4,216	4,365
Financial Liabilities:
Non-interest bearing Deposits	110,452	103,966
Time Deposits	236,360	269,507
Total deposits	776,464	763,252
Federal Home Loan Bank advances	4,500	11,600
Dividends payable	967	931
Carrying Amount [Member]
Financial Assets:
Cash and Cash Equivalents	19,263	44,092
Securities - available for sale	324,509	355,905
Other Securities	4,216	4,365
Loans, net	570,919	496,178
Interest receivable	3,694	3,603
Total Assets	922,601	904,143
Financial Liabilities:
Interest bearing Deposits	429,652	389,779
Non-interest bearing Deposits	110,452	103,966
Time Deposits	236,360	269,507
Total deposits	776,464	763,252
Short-term debt	69,756	51,312
Federal Home Loan Bank advances	4,500	11,600
Interest payable	223	288
Dividends payable	967	931
Total Liabilities	851,910	827,383
Fair Value [Member]
Financial Assets:
Cash and Cash Equivalents	19,263	44,092
Securities - available for sale	324,509	355,905
Other Securities	4,216	4,365
Loans, net	579,992	501,260
Interest receivable	3,694	3,603
Total Assets	931,674	909,225
Financial Liabilities:
Interest bearing Deposits	429,750	390,066
Non-interest bearing Deposits	111,239	104,529
Time Deposits	236,027	272,591
Total deposits	777,016	767,186
Short-term debt	69,756	51,312
Federal Home Loan Bank advances	4,570	11,012
Interest payable	223	288
Dividends payable	967	931
Total Liabilities	852,532	830,729
Level 1 [Member]
Financial Assets:
Cash and Cash Equivalents	19,263	44,092
Securities - available for sale	25,272	10,568
Other Securities
Loans, net
Interest receivable
Total Assets	44,535	54,660
Financial Liabilities:
Interest bearing Deposits
Non-interest bearing Deposits
Time Deposits
Total deposits
Short-term debt
Federal Home Loan Bank advances
Interest payable
Dividends payable
Total Liabilities
Level 2 [Member]
Financial Assets:
Cash and Cash Equivalents
Securities - available for sale	288,891	328,929
Other Securities
Loans, net
Interest receivable
Total Assets	288,891	328,929
Financial Liabilities:
Interest bearing Deposits
Non-interest bearing Deposits	111,239	104,529
Time Deposits
Total deposits	111,239	104,529
Short-term debt
Federal Home Loan Bank advances
Interest payable
Dividends payable	967	931
Total Liabilities	112,206	105,460
Level 3 [Member]
Financial Assets:
Cash and Cash Equivalents
Securities - available for sale	10,346	16,408
Other Securities	4,216	4,365
Loans, net	579,992	501,260
Interest receivable	3,694	3,603
Total Assets	598,248	525,636
Financial Liabilities:
Interest bearing Deposits	429,750	390,066
Non-interest bearing Deposits
Time Deposits	236,027	272,591
Total deposits	665,777	662,657
Short-term debt	69,756	51,312
Federal Home Loan Bank advances	4,570	11,012
Interest payable	223	288
Dividends payable
Total Liabilities	$ 740,326	$ 725,269