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Stock Incentive Plans - Summary of Fair Value of Stock Option Awards Under Black-Scholes Option-Pricing Model (Detail) - Stock Options [Member]
12 Months Ended
Dec. 31, 2018
$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Expected volatility 42.20%
Risk free interest rate 2.70%
Expected dividend yield 1.20%
Expected term 8 years 3 months 18 days
Weighted average fair value per share $ 36.41