Financial Instruments With Off-Balance Sheet Risk - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Loan Purchase Commitments
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Outstanding loan commitment under financial instrument off balance sheet risk	$ 38,200	$ 42,700
Unused lines of Credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Outstanding loan commitment under financial instrument off balance sheet risk	$ 452	$ 473

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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