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Stock-Based Compensation - Summary of Activity for SARs (Detail) - Stock Appreciation Rights (SARs) [Member]
3 Months Ended
Mar. 31, 2020
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
RSUs/SARs – beginning of period | shares 108,854
Exercised, Outstanding SARs | shares (16,216)
RSUs/SARs – end of period | shares 92,638
RSUs/SARs, Weighted Average Grant Date Fair Value, Beginning of period | $ / shares $ 29.05
Exercised, Weighted Average Grant Date Fair Value | $ / shares 23.87
RSUs/SARs, Weighted Average Grant Date Fair Value, end of period | $ / shares $ 30.0