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Stockholders' Equity and Stock Plans - Valuation Assumptions (Details) - Stock options
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk-free interest rate 0.98% 0.91% 2.51%
Expected dividend yield on common stock 2.57% 2.38% 1.75%
Expected life in years 6 years 1 month 6 days 6 years 1 month 6 days 5 years 9 months 18 days
Expected price volatility 33.12% 24.43% 22.71%