Other Borrowings - Summary of Other Borrowings (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Federal Home Loan Bank Borrowings By Year Of Maturity And Applicable Interest Rate [Line Items]
Total other borrowings	$ 39,000	$ 78,881	$ 100,293
Fixed Rate Advance One [Member]
Federal Home Loan Bank Borrowings By Year Of Maturity And Applicable Interest Rate [Line Items]
Debt instrument advances			5,000
Fixed Rate Advance Two [Member]
Federal Home Loan Bank Borrowings By Year Of Maturity And Applicable Interest Rate [Line Items]
Debt instrument advances			5,000
Fixed Rate Advance Three [Member]
Federal Home Loan Bank Borrowings By Year Of Maturity And Applicable Interest Rate [Line Items]
Debt instrument advances			3,000
Daily Rate Credit From Federal Home Loan Bank [Member]
Federal Home Loan Bank Borrowings By Year Of Maturity And Applicable Interest Rate [Line Items]
Debt instrument advances		35,000	40,000
Revolving Credit Facility 1 [Member]
Federal Home Loan Bank Borrowings By Year Of Maturity And Applicable Interest Rate [Line Items]
Debt instrument advances	24,000	24,000
Revolving Credit Facility [Member]
Federal Home Loan Bank Borrowings By Year Of Maturity And Applicable Interest Rate [Line Items]
Debt instrument advances			22,500
Correspondent Bank Advances [Member]
Federal Home Loan Bank Borrowings By Year Of Maturity And Applicable Interest Rate [Line Items]
Advance from correspondent bank with a fixed interest rate of 4.50%, due November 27, 2017, secured by subsidiary bank loan receivable		4,881	4,936
Subordinated Debt One [Member]
Federal Home Loan Bank Borrowings By Year Of Maturity And Applicable Interest Rate [Line Items]
Subordinated debt issued			5,000
Subordinated Debt Two [Member]
Federal Home Loan Bank Borrowings By Year Of Maturity And Applicable Interest Rate [Line Items]
Subordinated debt issued	$ 15,000	$ 15,000	$ 14,857