Loans Receivable and Allowance for Loan Losses - Additional Information (Detail) $ in Thousands		3 Months Ended		6 Months Ended
	Jul. 11, 2016 USD ($)	Jun. 30, 2016 USD ($) Allowance Commitment	Jun. 30, 2015 USD ($) Allowance	Jun. 30, 2016 USD ($) Allowance Commitment Loan	Jun. 30, 2015 USD ($) Allowance Loan	Dec. 31, 2015 USD ($) Commitment
Financing Receivable, Modifications [Line Items]
Funds for reimbursement		$ 1,200		$ 1,200		$ 1,200
Loans reported as TDR		$ 14,100		$ 14,100		$ 11,400
Minimum performance requirement				6 months
Sustained performance period				9 months
Number of commitments to lend additional funds (commitment) | Commitment		0		0		0
Number of loans modified as TDR (loan) | Loan					0
Loans modified as TDR allowance (allowance) | Allowance		0	2	0	2
Accounts Payable and Accrued Liabilities
Financing Receivable, Modifications [Line Items]
Settlement of FDIC loss sharing agreement		$ 1,400		$ 1,400
Subsequent Event
Financing Receivable, Modifications [Line Items]
Payments for early termination of FDIC loss sharing agreement	$ 1,400
Residential real estate
Financing Receivable, Modifications [Line Items]
Residential real estate held in other real estate owned		1,000		1,000		$ 1,200
Loans in process of foreclosure		$ 1,000		$ 1,000		$ 600
Loans modified as TDR allowance (allowance) | Allowance			1
Commercial and industrial
Financing Receivable, Modifications [Line Items]
Loans modified as TDR allowance (allowance) | Allowance			1		1
Allowance for credit losses, effect of change in method			$ 70		$ 70
Commercial real estate - non-owner occupied
Financing Receivable, Modifications [Line Items]
Loans modified as TDR allowance (allowance) | Allowance					1
Allowance for credit losses, effect of change in method			$ 20		$ 20
Manufactured housing
Financing Receivable, Modifications [Line Items]
Number of loans modified as TDR (loan) | Loan				2
Loans modified as TDR				$ 100