Loans Receivable - Recorded Investment and Unpaid Principal Balances for Impaired Loans Receivable (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Financing Receivable, Impaired [Line Items]
Recorded Investment	$ 16,830	$ 17,022
Unpaid Principal Balance	17,103	17,296
Related Allowance	1,351	1,061
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	13,957	14,385
Unpaid Principal Balance	14,227	14,655
Related Allowance	847	989
Commercial Real Estate [Member] | With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	2,834	3,139
Unpaid Principal Balance	2,940	3,246
Related Allowance
Commercial Real Estate [Member] | With an Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	11,123	11,246
Unpaid Principal Balance	11,287	11,409
Related Allowance	847	989
Residential Real Estate, Single Family [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	2,356	1,356
Unpaid Principal Balance	2,356	1,356
Related Allowance	401
Residential Real Estate, Single Family [Member] | With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	1,380	1,356
Unpaid Principal Balance	1,380	1,356
Related Allowance
Residential Real Estate, Single Family [Member] | With an Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	976
Unpaid Principal Balance	976
Related Allowance	401
Residential Construction Loans [Member] | With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment		850
Unpaid Principal Balance		850
Related Allowance
Consumer Home Equity [Member] | With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	286	249
Unpaid Principal Balance	289	253
Related Allowance
Consumer Home Equity [Member] | With an Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	148	149
Unpaid Principal Balance	148	149
Related Allowance	44	45
Consumer Dealer Auto and RV Loans [Member] | With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	24	6
Unpaid Principal Balance	24	6
Related Allowance
Consumer Dealer Auto and RV Loans [Member] | With an Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	3	3
Unpaid Principal Balance	3	3
Related Allowance	3	3
Commercial Business [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	56	24
Unpaid Principal Balance	56	24
Related Allowance	56	24
Commercial Business [Member] | With an Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	56	24
Unpaid Principal Balance	56	24
Related Allowance	56	24
Residential Construction [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment		850
Unpaid Principal Balance		850
Related Allowance
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	461	407
Unpaid Principal Balance	464	411
Related Allowance	$ 47	$ 48