Consolidated Balance Sheets Details (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Loans, allowance for loan losses	$ 8,320	$ 7,470
Accumulated depreciation	$ 21,916	$ 23,774
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)	7,634,918	7,596,351
Common stock, shares outstanding (in shares)	6,172,378	6,176,556
Treasury stock, shares (in shares)	1,462,540	1,419,795

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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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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