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Retirement Plans - Schedule of Actuarial Assumptions Used in Determination of Net Periodic Pension Cost (Detail)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Retirement Benefits [Abstract]      
Weighted average discount rate 4.16% 4.19% 3.96%
Rates of increase in compensation levels 3.50% 3.50% 3.50%
Expected long-term rate of return on assets 7.25% 7.25% 7.25%