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Stock-based Compensation Plans - Discounted Stock Purchase Plan Assumptions and Resulting Weighted Average Fair Value (Detail) - DSPP - $ / shares
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Dividend yield 2.00% 4.00% 5.30%
Expected volatility 67.00% 43.00% 30.00%
Risk-free interest rate 0.07% 0.88% 2.30%
Weighted-average fair value per share $ 6.72 $ 5.38 $ 5.81