Significant Accounting Policies - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Significant Accounting Policies [Line Items]
Personal loans charged off period no later than period	180 days
Percentage of excess loan balance for watch category	90.00%
Impaired loans measurement	Impaired loans measured for impairment generally include (1) non-accruing Special mention, Substandard and Doubtful loans in excess of $250,000; (2) Substandard and Doubtful loans in excess of $500,000; (3) Special Mention loans in excess of $500,000 if any of the loans in the relationship are more than 30 days past due or if the borrower has filed for bankruptcy; and (4) all TDRs.
Loan Receivables	$ 169,332,000	$ 161,033,000
Special Mention
Significant Accounting Policies [Line Items]
Loan Receivables	$ 489,000	$ 2,030,000
Loan due days	30 days
Residential First Mortgages
Significant Accounting Policies [Line Items]
Minimum balance in order to assign a risk rating grade	$ 1,000,000
Consumer and Other Loans
Significant Accounting Policies [Line Items]
Minimum balance in order to assign a risk rating grade	$ 250,000
Minimum
Significant Accounting Policies [Line Items]
Number of days past due for a loan to remain on accrual status	90 days
Minimum | Non-accruing Special mention, Substandard and Doubtful loans
Significant Accounting Policies [Line Items]
Loan Receivables	$ 250,000
Minimum | Substandard and Doubtful loans
Significant Accounting Policies [Line Items]
Loan Receivables	500,000
Minimum | Special Mention
Significant Accounting Policies [Line Items]
Loan Receivables	$ 500,000