Fair Values - Summary of Fair Value of Financial Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Aug. 31, 2012
Financial assets - Continued operations
Securities available-for-sale	$ 209,642	$ 197,354	$ 18,800
Securities held-to-maturity	31,902
Financial liabilities - Continued operations
Federal Home Loan Bank advances	75,000
Standby letters of credit [Member]
Off balance sheet financial instruments:
Contract Amount	4,011	3,012
Continued operations [Member] | Fair Value [Member]
Financial assets - Continued operations
Cash and cash equivalents	48,995	45,068
Securities available-for-sale	209,642	197,354
Securities held-to-maturity	31,902	31,493
Portfolio loans, net	590,780	664,119
Promissory note due from the Mortgage Company	2,943	3,592
Federal Home Loan Bank Stock	5,529	5,875
Financial liabilities - Continued operations
Deposits	725,790	702,817
Securities sold under agreements to repurchase	0	13,095
Federal Home Loan Bank advances	75,000	125,231
Subordinated debenture	8,580	8,109
Derivatives	2,844	4,085
Continued operations [Member] | Carrying Amounts [Member]
Financial assets - Continued operations
Cash and cash equivalents	48,995	45,068
Securities available-for-sale	209,642	197,354
Securities held-to-maturity	34,814	31,483
Portfolio loans, net	581,302	653,260
Promissory note due from the Mortgage Company	2,943	3,592
Federal Home Loan Bank Stock	5,529	5,875
Financial liabilities - Continued operations
Deposits	725,523	701,052
Securities sold under agreements to repurchase	0	13,095
Federal Home Loan Bank advances	75,000	125,000
Subordinated debenture	15,465	15,465
Derivatives	2,844	4,085
Commitments to extend credit [Member]
Off balance sheet financial instruments:
Contract Amount	181,569	144,333
Guaranteed commitments outstanding [Member]
Off balance sheet financial instruments:
Contract Amount	$ 1,874	$ 1,290