Consolidated Balance Sheets Details (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Loans, allowance for loan losses	$ 5,762	$ 5,055
Accumulated depreciation	$ 22,570	$ 21,437
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	10,000,000	10,000,000
Common stock, shares issued (in shares)	7,568,053	7,562,264
Common stock, shares outstanding (in shares)	6,157,692	6,298,062
Treasury stock, shares (in shares)	1,410,361	1,264,202

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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