XML 112 R52.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Pension Plans - Additional Information (Detail) - USD ($)
 12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Pension And Other Employee Benefit Plans [Line Items]      
Estimated net loss for the PLP-USA pension plan in 2019 $ 500,000    
Prior service cost 0    
Pre-tax unfunded pension obligation gain (loss) $ (200,000)    
Discount rate 3.50% 4.25%  
Asset performance rate of return assumption 7.00%    
Expected long-term return on plan assets 7.00% 8.00% 8.00%
Contribution to pension plan $ 0    
Expense for contribution plan 6,000,000 $ 5,600,000 $ 5,100,000
Expense for the supplemental profit sharing plan 1,100,000 200,000 $ 500,000
Supplemental profit sharing plan unfunded status 6,100,000 $ 4,900,000  
Decrease in Discount Rate [Member]      
Pension And Other Employee Benefit Plans [Line Items]      
Pre-tax unfunded pension obligation gain (loss) $ (4,000,000)    
Discount rate 0.75%    
Gain on Industry Updates to Mortality Table [Member] | Maximum [Member]      
Pension And Other Employee Benefit Plans [Line Items]      
Pre-tax unfunded pension obligation gain (loss) $ 100,000    
Demographic Changes [Member]      
Pension And Other Employee Benefit Plans [Line Items]      
Pre-tax unfunded pension obligation gain (loss) 200,000    
Asset Performance [Member]      
Pension And Other Employee Benefit Plans [Line Items]      
Pre-tax unfunded pension obligation gain (loss) 3,300,000    
Service Cost Expense Load [Member]      
Pension And Other Employee Benefit Plans [Line Items]      
Pre-tax unfunded pension obligation gain (loss) $ 300,000