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Stockholders' Equity and Stock Plans - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 12 Months Ended |
--- | --- | --- | ---
Jan. 25, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2017 | Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Total compensation cost for share-based payment arrangements |  | $ 522 | $ 962 | $ 972 |  |
Share-based compensation income tax benefit recognized |  | 146 | 257 | 213 |  |
Unrecognized compensation expense |  | $ 1,300 |  |  |  |
Period for recognizing unrecognized compensation expense |  | 2 years 2 months 12 days |  |  |  |
Excess tax benefits recorded as a reduction to income tax expense |  | $ 2 | 3 | 87 |  |
Subsequent event |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Dividends declared per common share (usd per share) | $ 0.25 |  |  |  |  |
Stock options |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Total grant-date fair value of option shares vested |  | $ 255 | 356 | 514 |  |
Stock options | Officers and Employees |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting period |  | 3 years |  |  |  |
Expiration period of grants |  | 10 years |  |  |  |
Stock options | Officers and Employees | Share-Based Payment Arrangement, Tranche One |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting percentage |  | 33.33% |  |  |  |
Stock options | Officers and Employees | Share-Based Payment Arrangement, Tranche Two |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting percentage |  | 33.33% |  |  |  |
Stock options | Officers and Employees | Share-Based Payment Arrangement, Tranche Three |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting percentage |  | 33.33% |  |  |  |
Stock options | Non-Employee Directors |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Expiration period of grants |  | 10 years |  |  |  |
Performance shares |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting period |  | 3 years |  |  |  |
Restricted stock award |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Total grant-date fair value of option shares vested |  | $ 428 | $ 431 | $ 1,000 |  |
Minimum | Performance shares |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting percentage |  | 0.00% |  |  |  |
Maximum | Performance shares |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting percentage |  | 200.00% |  |  |  |
The Plan, 2020 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares approved to be issued in common stock (in shares) |  |  |  |  |  | 250,000
Number of shares available for future grants under plan (in shares) |  | 209,642 |  |  |  |
Employee Stock Purchase Plan, 2007 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of shares available for future grants under plan (in shares) |  | 372,923 |  |  |  |
Discount from closing market price at end of each quarter |  |  |  |  | 5.00% |
Employee Stock Purchase Plan, 2007 | Minimum |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Approved payroll deduction to purchase shares, percentage |  |  |  |  | 1.00% |
Employee Stock Purchase Plan, 2007 | Maximum |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Approved payroll deduction to purchase shares, percentage |  |  |  |  | 15.00% |
The 2017 Equity Plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of shares available for future grants under plan (in shares) |  | 790,201 |  |  |  |
Common Stock | The Plan, 2020 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares awarded in period from plan (in shares) |  | 18,362 | 10,145 | 6,443 |  |

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