XML 124 R109.htm IDEA: XBRL DOCUMENT v3.22.0.1
Employee Benefits - Additional Information (Detail) - USD ($)
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]      
Percentage of company stock held equal to plan assets 13.00%    
Period of obligations for retired lives in trust 30 years    
Long term inflation rate 2.50%    
Expense recognized under 401(K) plan $ 6,000,000 $ 6,000,000  
Contribution to Health & Welfare Plan to pay premiums and claims in the next fiscal year $ 1,000,000    
Minimum      
Defined Benefit Plan Disclosure [Line Items]      
Expected rate of return on equity security 6.00%    
Expected rate of return on fixed income security 3.00%    
Overall expected rate of return 5.00%    
Maximum      
Defined Benefit Plan Disclosure [Line Items]      
Expected rate of return on equity security 8.00%    
Expected rate of return on fixed income security 5.00%    
Overall expected rate of return 7.00%    
Pension Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Estimated unrecognized net actuarial loss (gain) that will be amortized from accumulated other comprehensive loss into net periodic benefit cost $ (2,000,000)    
Amount recognized of net actuarial loss into net periodic benefit cost 7,000,000 $ 7,000,000 $ 10,000,000
Estimated prior service cost that will be amortized from accumulated other comprehensive loss (gain) into net periodic benefit cost 0    
Amortization of past-service liability $ 0    
Discount rates used to determine the benefit obligation 2.60% 2.20%  
Percentage of assets allocated to equities to be considered well funded 55.00%    
Percentage of assets allocated to fixed income to be considered well funded 44.00%    
Defined benefit plan cash equivalent portfolio percentage 1.00%    
Post-Retirement Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Amount recognized of net actuarial loss into net periodic benefit cost $ 0 $ 0 0
Estimated prior service cost that will be amortized from accumulated other comprehensive loss (gain) into net periodic benefit cost 0    
Amortization of past-service liability $ 0 $ (0) $ (0)
Discount rates used to determine the benefit obligation 2.30% 2.00%